Change state manager methods to return the new state

Co-authored-by: Paul <ritter.paul1@gmail.com>

.github/CODEOWNERS

@@ -1,7 +1,20 @@
 # Last match in file takes precedence.
 
+# Ping for all PRs
+* @Acruid @PJB3005 @Silvertorch5
+
+/Robust.*/Audio/Midi/ @Zumorica
+
+/Robust.Client.NameGenerator @PaulRitter
+/Robust.Client.Injectors @PaulRitter
+/Robust.Generators @PaulRitter
+/Robust.Analyzers @PaulRitter
+/Robust.*/GameStates @PaulRitter
+/Robust.Shared/Analyzers @PaulRitter
+/Robust.*/Serialization @PaulRitter @DrSmugleaf
+/Robust.*/Prototypes @PaulRitter
+/Robust.Shared/GameObjects/ComponentDependencies @PaulRitter
+/Robust.*/Containers @PaulRitter
+
 # Be they Fluent translations or Freemarker templates, I know them both!
 *.ftl @RemieRichards
-
-# Ping for all PRs
-* @Acruid @PJB3005 @Silvertorch5

.github/workflows/benchmarks.yml

@@ -0,0 +1,35 @@
+name: Benchmarks
+on:
+  workflow_dispatch:
+  schedule:
+    - cron: '0 5 * * *'
+  push:
+    tags:
+      - 'v*'
+
+concurrency: benchmarks
+
+env:
+  ROBUST_BENCHMARKS_ENABLE_SQL: 1
+  ROBUST_BENCHMARKS_SQL_ADDRESS: ${{ secrets.BENCHMARKS_WRITE_ADDRESS }}
+  ROBUST_BENCHMARKS_SQL_PORT: ${{ secrets.BENCHMARKS_WRITE_PORT }}
+  ROBUST_BENCHMARKS_SQL_USER: ${{ secrets.BENCHMARKS_WRITE_USER }}
+  ROBUST_BENCHMARKS_SQL_PASSWORD: ${{ secrets.BENCHMARKS_WRITE_PASSWORD }}
+  ROBUST_BENCHMARKS_SQL_DATABASE: benchmarks
+
+jobs:
+  benchmark:
+    name: Run Benchmarks
+    runs-on: ubuntu-latest
+    steps:
+    - name: Run script on centcomm
+      uses: appleboy/ssh-action@master
+      with:
+        host: centcomm.spacestation14.io
+        username: robust-benchmark-runner
+        key: ${{ secrets.CENTCOMM_ROBUST_BENCHMARK_RUNNER_KEY }}
+        command_timeout: 100000m 
+        script: |
+          wget https://raw.githubusercontent.com/space-wizards/RobustToolbox/${{ github.sha }}/Tools/run_benchmarks.py
+          python3 run_benchmarks.py "${{ secrets.BENCHMARKS_WRITE_ADDRESS }}" "${{ secrets.BENCHMARKS_WRITE_PORT }}" "${{ secrets.BENCHMARKS_WRITE_USER }}" "${{ secrets.BENCHMARKS_WRITE_PASSWORD }}" "${{ github.sha }}"
+          rm run_benchmarks.py

.github/workflows/build-docfx.yml

@@ -0,0 +1,34 @@
+name: Build & Publish DocFX
+
+on:
+  schedule:
+    - cron: "0 0 * * 0"
+jobs:
+  docfx:
+   runs-on: ubuntu-latest
+   steps: 
+    - uses: actions/checkout@v2
+      with:
+        submodules: true
+
+    - name: Setup .NET Core
+      uses: actions/setup-dotnet@v1
+      with:
+        dotnet-version: 6.0.x
+        
+    - name: Install dependencies
+      run: dotnet restore
+      
+    - name: Build Project
+      run: dotnet build --no-restore /p:WarningsAsErrors=nullable
+
+    - name: Build DocFX
+      uses: nikeee/docfx-action@v1.0.0      
+      with:
+        args: Robust.Docfx/docfx.json
+    
+    - name: Publish Docfx Documentation on GitHub Pages
+      uses: maxheld83/ghpages@master
+      env:
+        BUILD_DIR: Robust.Docfx/_robust-site 
+        GH_PAT: ${{ secrets.GH_PAT }} 

.github/workflows/build-test.yml

@@ -22,10 +22,12 @@ jobs:
     - name: Setup .NET Core
       uses: actions/setup-dotnet@v1
       with:
-        dotnet-version: 6.0.100
+        dotnet-version: 6.0.x
     - name: Install dependencies
       run: dotnet restore
     - name: Build
       run: dotnet build --no-restore /p:WarningsAsErrors=nullable
     - name: Test Engine
-      run: dotnet test --no-build Robust.UnitTesting/Robust.UnitTesting.csproj -v n
+      run: dotnet test --no-build Robust.UnitTesting/Robust.UnitTesting.csproj -- NUnit.ConsoleOut=0
+ 
+

.gitignore

@@ -41,18 +41,6 @@ _ReSharper*/
 
 # Resources
 *.resources
-/Resources/textures/Animations/*.*
-/Resources/ResourcePack.zip
-/Resources/textures/*_Animations.png
-/Resources/textures/*_Decals.png
-/Resources/textures/*_Effects.png
-/Resources/textures/*_Items.png
-/Resources/textures/*_Objects.png
-/Resources/textures/*_Tiles.png
-/Resources/textures/*_UserInterface.png
-/Resources/textures/*.TAI
-/Resources/SpriteRenderer/Ogre.log
-/Resources/Spriterenderer/output
 /Media
 /setenv.bat
 
@@ -78,16 +66,6 @@ project.lock.json
 # Created by NUnit.
 TestResult.xml
 
-NetSerializerDebug.dll
-
-# We're not gonna ship Mac extlibs with the repo due to size. (11 MB)
-Third-Party/extlibs/Mac/
-# Or the automatically-fetched Windows natives, for that matter.
-Third-Party/extlibs/Windows/
-
-# Actually I'll make this folder because SS14.Shared.Bsdiff isn't third-party is it?
-Dependencies/
-
 # Python stuff
 __pycache__
 .mypy_cache
@@ -98,3 +76,5 @@ MSBuild/Robust.Custom.targets
 
 
 release/
+Robust.Docfx/*-site
+Robust.Docfx/api

.gitmodules

@@ -10,12 +10,6 @@
 [submodule "Robust.LoaderApi"]
 	path = Robust.LoaderApi
 	url = https://github.com/space-wizards/Robust.LoaderApi.git
-[submodule "ManagedHttpListener"]
-	path = ManagedHttpListener
-	url = https://github.com/space-wizards/ManagedHttpListener.git
-[submodule "Linguini"]
-	path = Linguini
-	url = https://github.com/space-wizards/Linguini
 [submodule "cefglue"]
 	path = cefglue
 	url = https://github.com/space-wizards/cefglue.git

MSBuild/Robust.Engine.Version.props

@@ -1,4 +1,4 @@
 <Project>
     <!-- This file automatically reset by Tools/version.py -->
-    <PropertyGroup><Version>0.8.7</Version></PropertyGroup>
+    <PropertyGroup><Version>0.40.3.0</Version></PropertyGroup>
 </Project>

MSBuild/XamlIL.targets

@@ -2,7 +2,7 @@
   <PropertyGroup>
     <!-- Avoid MSBuild adding a None entry for XAML files because they'd show up TWICE in the project view. -->
     <DefaultItemExcludes>**/*.xaml</DefaultItemExcludes>
-    <RobustUseExternalMSBuild>true</RobustUseExternalMSBuild>
+    <RobustUseExternalMSBuild>false</RobustUseExternalMSBuild>
     <_RobustUseExternalMSBuild>$(RobustUseExternalMSBuild)</_RobustUseExternalMSBuild>
     <_RobustUseExternalMSBuild Condition="'$(_RobustForceInternalMSBuild)' == 'true'">false</_RobustUseExternalMSBuild>
   </PropertyGroup>

OpenToolkit.GraphicsLibraryFramework/GLFW.cs

@@ -10,7 +10,6 @@
 using System;
 using System.Runtime.InteropServices;
 using static OpenToolkit.GraphicsLibraryFramework.GLFWNative;
-using static Robust.Shared.Utility.MarshalHelper;
 
 namespace OpenToolkit.GraphicsLibraryFramework
 {
@@ -211,7 +210,7 @@ namespace OpenToolkit.GraphicsLibraryFramework
         /// <seealso cref="GetVersion"/>
         public static unsafe string GetVersionString()
         {
-            return PtrToStringUTF8(glfwGetVersionString());
+            return Marshal.PtrToStringUTF8((IntPtr) glfwGetVersionString());
         }
 
         /// <summary>
@@ -272,7 +271,7 @@ namespace OpenToolkit.GraphicsLibraryFramework
         {
             byte* desc;
             var code = glfwGetError(&desc);
-            description = PtrToStringUTF8(desc);
+            description = Marshal.PtrToStringUTF8((IntPtr) desc);
             return code;
         }
 
@@ -590,7 +589,7 @@ namespace OpenToolkit.GraphicsLibraryFramework
         /// </remarks>
         public static unsafe string GetMonitorName(Monitor* monitor)
         {
-            return PtrToStringUTF8(glfwGetMonitorName(monitor));
+            return Marshal.PtrToStringUTF8((IntPtr) glfwGetMonitorName(monitor));
         }
 
         /// <summary>
@@ -902,7 +901,7 @@ namespace OpenToolkit.GraphicsLibraryFramework
         /// </remarks>
         public static unsafe void WindowHint(WindowHintString hint, string value)
         {
-            var ptr = StringToCoTaskMemUTF8(value);
+            var ptr = Marshal.StringToCoTaskMemUTF8(value);
 
             try
             {
@@ -1364,7 +1363,7 @@ namespace OpenToolkit.GraphicsLibraryFramework
         /// </remarks>
         public static unsafe string GetKeyName(Keys key, int scanCode)
         {
-            return PtrToStringUTF8(glfwGetKeyName(key, scanCode));
+            return Marshal.PtrToStringUTF8((IntPtr) glfwGetKeyName(key, scanCode));
         }
 
         /// <summary>
@@ -2278,7 +2277,7 @@ namespace OpenToolkit.GraphicsLibraryFramework
         /// </remarks>
         public static unsafe string GetJoystickName(int jid)
         {
-            return PtrToStringUTF8(glfwGetJoystickName(jid));
+            return Marshal.PtrToStringUTF8((IntPtr) glfwGetJoystickName(jid));
         }
 
         /// <summary>
@@ -2351,7 +2350,7 @@ namespace OpenToolkit.GraphicsLibraryFramework
         /// </remarks>
         public static unsafe string GetJoystickGUID(int jid)
         {
-            return PtrToStringUTF8(glfwGetJoystickGUID(jid));
+            return Marshal.PtrToStringUTF8((IntPtr) glfwGetJoystickGUID(jid));
         }
 
         /// <summary>
@@ -2509,7 +2508,7 @@ namespace OpenToolkit.GraphicsLibraryFramework
         /// </remarks>
         public static unsafe bool UpdateGamepadMappings(string newMapping)
         {
-            var ptr = StringToCoTaskMemUTF8(newMapping);
+            var ptr = Marshal.StringToCoTaskMemUTF8(newMapping);
             try
             {
                 return glfwUpdateGamepadMappings((byte*)ptr) == GLFW_TRUE;
@@ -2585,7 +2584,7 @@ namespace OpenToolkit.GraphicsLibraryFramework
         /// </remarks>
         public static unsafe string GetGamepadName(int jid)
         {
-            return PtrToStringUTF8(glfwGetGamepadName(jid));
+            return Marshal.PtrToStringUTF8((IntPtr) glfwGetGamepadName(jid));
         }
 
         /// <summary>
@@ -2854,7 +2853,7 @@ namespace OpenToolkit.GraphicsLibraryFramework
         /// </remarks>
         public static unsafe bool ExtensionSupported(string extensionName)
         {
-            var ptr = StringToCoTaskMemUTF8(extensionName);
+            var ptr = Marshal.StringToCoTaskMemUTF8(extensionName);
 
             try
             {
@@ -2893,7 +2892,7 @@ namespace OpenToolkit.GraphicsLibraryFramework
         /// <seealso cref="ExtensionSupported" />
         public static unsafe IntPtr GetProcAddress(string procName)
         {
-            var ptr = StringToCoTaskMemUTF8(procName);
+            var ptr = Marshal.StringToCoTaskMemUTF8(procName);
 
             try
             {
@@ -3085,7 +3084,7 @@ namespace OpenToolkit.GraphicsLibraryFramework
         /// </remarks>
         public static unsafe Window* CreateWindow(int width, int height, string title, Monitor* monitor, Window* share)
         {
-            var ptr = StringToCoTaskMemUTF8(title);
+            var ptr = Marshal.StringToCoTaskMemUTF8(title);
 
             try
             {
@@ -3306,7 +3305,7 @@ namespace OpenToolkit.GraphicsLibraryFramework
         /// <seealso cref="SetClipboardString"/>
         public static unsafe string GetClipboardString(Window* window)
         {
-            return PtrToStringUTF8(glfwGetClipboardString(window));
+            return Marshal.PtrToStringUTF8((IntPtr) glfwGetClipboardString(window));
         }
 
         /// <summary>
@@ -3917,7 +3916,7 @@ namespace OpenToolkit.GraphicsLibraryFramework
         /// <seealso cref="GetClipboardString"/>
         public static unsafe void SetClipboardString(Window* window, string data)
         {
-            var ptr = StringToCoTaskMemUTF8(data);
+            var ptr = Marshal.StringToCoTaskMemUTF8(data);
 
             try
             {
@@ -4751,7 +4750,7 @@ namespace OpenToolkit.GraphicsLibraryFramework
         /// </remarks>
         public static unsafe void SetWindowTitle(Window* window, string title)
         {
-            var ptr = StringToCoTaskMemUTF8(title);
+            var ptr = Marshal.StringToCoTaskMemUTF8(title);
 
             try
             {
@@ -5340,7 +5339,7 @@ namespace OpenToolkit.GraphicsLibraryFramework
             var array = new string[count];
             for (var i = 0; i < count; i++)
             {
-                array[i] = PtrToStringUTF8(ptr[i]);
+                array[i] = Marshal.PtrToStringUTF8((IntPtr) ptr[i]);
             }
 
             return array;
@@ -5386,7 +5385,7 @@ namespace OpenToolkit.GraphicsLibraryFramework
         /// <returns>The address of the function, or <c>null</c> if an error occurred.</returns>
         public static unsafe IntPtr GetInstanceProcAddress(VkHandle instance, string procName)
         {
-            var ptr = StringToCoTaskMemUTF8(procName);
+            var ptr = Marshal.StringToCoTaskMemUTF8(procName);
 
             try
             {

OpenToolkit.GraphicsLibraryFramework/OpenToolkit.GraphicsLibraryFramework.csproj

@@ -14,7 +14,4 @@
     <PackageReference Condition="'$(TargetFramework)' == 'net472'" Include="System.Memory" Version="4.5.3" />
   </ItemGroup>
 
-  <ItemGroup>
-    <ProjectReference Include="..\Robust.Shared\Robust.Shared.csproj" />
-  </ItemGroup>
 </Project>

Resources/.gitignore

@@ -1,8 +0,0 @@
-# .import files are made by Godot because the assets are exposed if using symlinks.
-# IF you need to persist a .import file because of something used Godot-side (GUI-side),
-# you can do a negation with !.
-*.import
-# Negation would be like this:
-#!/Textures/UserInterface/1pxwhite.png.import
-!/Scenes/SS14Window/closewindow.png.import
-/I_MADE_THE_SYMLINK

Resources/Locale/en-US/commands.ftl

@@ -0,0 +1,155 @@
+### Localization for engine console commands
+
+## generic
+
+cmd-parse-failure-integer = {$arg} is not a valid integer.
+cmd-parse-failure-float = {$arg} is not a valid float.
+cmd-parse-failure-bool = {$arg} is not a valid bool.
+
+
+## 'help' command
+cmd-help-desc = Display general help or help text for a specific command
+cmd-help-help = Usage: help [command name]
+    When no command name is provided, displays general-purpose help text. If a command name is provided, displays help text for that command.
+
+cmd-help-no-args = To display help for a specific command, write 'help <command>'. To list all available commands, write 'list'. To search for commands, use 'list <filter>'.
+cmd-help-unknown = Unknown command: { $command }
+cmd-help-top = { $command } - { $description }
+cmd-help-invalid-args = Invalid amount of arguments.
+cmd-help-arg-cmdname = [command name]
+
+## 'cvar' command
+cmd-cvar-desc = Gets or sets a CVar.
+cmd-cvar-help = Usage: cvar <name | ?> [value]
+    If a value is passed, the value is parsed and stored as the new value of the CVar.
+    If not, the current value of the CVar is displayed.
+    Use 'cvar ?' to get a list of all registered CVars.
+
+cmd-cvar-invalid-args = Must provide exactly one or two arguments.
+cmd-cvar-not-registered = CVar '{ $cvar }' is not registered. Use 'cvar ?' to get a list of all registered CVars.
+cmd-cvar-parse-error = Input value is in incorrect format for type { $type }
+cmd-cvar-compl-list = List available CVars
+cmd-cvar-arg-name = <name | ?>
+cmd-cvar-value-hidden = <value hidden>
+
+## 'list' command
+cmd-list-desc = Lists available commands, with optional search filter
+cmd-list-help = Usage: list [filter]
+    Lists all available commands. If an argument is provided, it will be used to filter commands by name.
+
+cmd-list-heading = SIDE NAME            DESC{"\u000A"}-------------------------{"\u000A"}
+
+cmd-list-arg-filter = [filter]
+
+## '>' command, aka remote exec
+cmd-remoteexec-desc = Executes server-side commands
+cmd-remoteexec-help = Usage: > <command> [arg] [arg] [arg...]
+    Executes a command on the server. This is necessary if a command with the same name exists on the client, as simply running the command would run the client command first.
+
+## 'gc' command
+cmd-gc-desc = Run the GC (Garbage Collector)
+cmd-gc-help = Usage: gc [generation]
+    Uses GC.Collect() to execute the Garbage Collector.
+    If an argument is provided, it is parsed as a GC generation number and GC.Collect(int) is used.
+    Use the 'gfc' command to do an LOH-compacting full GC.
+cmd-gc-failed-parse = Failed to parse argument.
+cmd-gc-arg-generation = [generation]
+
+## 'gcf' command
+cmd-gcf-desc = Run the GC, fully, compacting LOH and everything.
+cmd-gcf-help = Usage: gcf
+    Does a full GC.Collect(2, GCCollectionMode.Forced, true, true) while also compacting LOH.
+    This will probably lock up for hundreds of milliseconds, be warned.
+
+## 'gc_mode' command
+cmd-gc_mode-desc = Change/Read the GC Latency mode
+cmd-gc_mode-help = Usage: gc_mode [type]
+    If no argument is provided, returns the current GC latency mode.
+    If an argument is passed, it is parsed as GCLatencyMode and set as the GC latency mode.
+
+cmd-gc_mode-current = current gc latency mode: { $prevMode }
+cmd-gc_mode-possible = possible modes:
+cmd-gc_mode-option = - { $mode }
+cmd-gc_mode-unknown = unknown gc latency mode: { $arg }
+cmd-gc_mode-attempt = attempting gc latency mode change: { $prevMode } -> { $mode }
+cmd-gc_mode-result = resulting gc latency mode: { $mode }
+cmd-gc_mode-arg-type = [type]
+
+## 'mem' command
+cmd-mem-desc = Prints managed memory info
+cmd-mem-help = Usage: mem
+
+cmd-mem-report = Heap Size: { TOSTRING($heapSize, "N0") }
+    Total Allocated: { TOSTRING($totalAllocated, "N0") }
+
+## 'physics' command
+cmd-physics-overlay = {$overlay} is not a recognised overlay
+
+## 'lsasm' command
+cmd-lsasm-desc = Lists loaded assemblies by load context
+cmd-lsasm-help = Usage: lsasm
+
+## 'exec' command
+cmd-exec-desc = Executes a script file from the game's writeable user data
+cmd-exec-help = Usage: exec <fileName>
+    Each line in the file is executed as a single command, unless it starts with a #
+
+cmd-exec-arg-filename = <fileName>
+
+## 'dump_net_comps' command
+cmd-dump_net_comps-desc = Prints the table of networked components.
+cmd-dump_net_comps-help = Usage: dump_net-comps
+
+cmd-dump_net_comps-error-writeable = Registration still writeable, network ids have not been generated.
+cmd-dump_net_comps-header = Networked Component Registrations:
+
+## 'dump_event_tables' command
+cmd-dump_event_tables-desc = Prints directed event tables for an entity.
+cmd-dump_event_tables-help = Usage: dump_event_tables <entityUid>
+
+cmd-dump_event_tables-missing-arg-entity = Missing entity argument
+cmd-dump_event_tables-error-entity = Invalid entity
+cmd-dump_event_tables-arg-entity = <entityUid>
+
+## 'monitor' command
+cmd-monitor-desc = Toggles a debug monitor in the F3 menu.
+cmd-monitor-help = Usage: monitor <name>
+    Possible monitors are: { $monitors }
+    You can also use the special values "-all" and "+all" to hide or show all monitors, respectively.
+
+cmd-monitor-arg-monitor = <monitor>
+cmd-monitor-invalid-name = Invalid monitor name
+cmd-monitor-arg-count = Missing monitor argument
+cmd-monitor-minus-all-hint = Hides all monitors
+cmd-monitor-plus-all-hint = Shows all monitors
+
+
+## Mapping commands
+
+cmd-savemap-desc = Serializes a map to disk. Will not save a post-init map unless forced.
+cmd-savemap-help = savemap <MapID> <Path> [force]
+cmd-savemap-not-exist = Target map does not exist.
+cmd-savemap-init-warning = Attempted to save a post-init map without forcing the save.
+cmd-savemap-attempt = Attempting to save map {$mapId} to {$path}.
+cmd-savemap-success = Map successfully saved.
+cmd-hint-savemap-id = <MapID>
+cmd-hint-savemap-path = <Path>
+cmd-hint-savemap-force = [bool]
+
+cmd-loadmap-desc = Loads a map from disk into the game.
+cmd-loadmap-help = loadmap <MapID> <Path> [x] [y] [rotation] [consistentUids]
+cmd-loadmap-nullspace = You cannot load into map 0.
+cmd-loadmap-exists = Map {$mapId} already exists.
+cmd-loadmap-success = Map {$mapId} has been loaded from {$path}.
+cmd-loadmap-error = An error occurred while loading map from {$path}.
+cmd-hint-loadmap-x-position = [x-position]
+cmd-hint-loadmap-y-position = [y-position]
+cmd-hint-loadmap-rotation = [rotation]
+cmd-hint-loadmap-uids = [float]
+
+## 'flushcookies' command
+# Note: the flushcookies command is from Robust.Client.WebView, it's not in the main engine code.
+
+cmd-flushcookies-desc = Flush CEF cookie storage to disk
+cmd-flushcookies-help = This ensure cookies are properly saved to disk in the event of unclean shutdowns.
+    Note that the actual operation is asynchronous.

Resources/Locale/en-US/controls.ftl

@@ -0,0 +1,10 @@
+color-selector-sliders-red = R
+color-selector-sliders-green = G
+color-selector-sliders-blue = B
+color-selector-sliders-hue = H
+color-selector-sliders-saturation = S
+color-selector-sliders-value = V
+color-selector-sliders-alpha = A
+
+color-selector-sliders-rgb = RGB
+color-selector-sliders-hsv = HSV

Resources/Locale/en-US/defaultwindow.ftl

@@ -0,0 +1 @@
+defaultwindow-placeholder-title = Exemplary Window Title Here

Resources/Locale/en-US/midi-commands.ftl

@@ -0,0 +1 @@
+midi-panic-command-description = Turns off every note for every active MIDI renderer.

Resources/Locale/en-US/ss14window.ftl

@@ -1 +0,0 @@
-ss14window-placeholder-title = Exemplary Window Title Here

Resources/Textures/Logo/logo.png.yml

@@ -1,2 +0,0 @@
-sample:
-  filter: true

Resources/Textures/Logo/logo.svg

@@ -1,152 +0,0 @@
-<?xml version="1.0" encoding="UTF-8" standalone="no"?>
-<!-- Created with Inkscape (http://www.inkscape.org/) -->
-
-<svg
-   xmlns:dc="http://purl.org/dc/elements/1.1/"
-   xmlns:cc="http://creativecommons.org/ns#"
-   xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
-   xmlns:svg="http://www.w3.org/2000/svg"
-   xmlns="http://www.w3.org/2000/svg"
-   xmlns:sodipodi="http://sodipodi.sourceforge.net/DTD/sodipodi-0.dtd"
-   xmlns:inkscape="http://www.inkscape.org/namespaces/inkscape"
-   width="113.67364mm"
-   height="56.37999mm"
-   viewBox="0 0 113.67364 56.37999"
-   version="1.1"
-   id="svg3223"
-   inkscape:version="0.92.4 5da689c313, 2019-01-14"
-   sodipodi:docname="logo.svg"
-   inkscape:export-filename="/home/pj/Projects/space-station-14/RobustToolbox/Resources/Textures/Logo/logo.png"
-   inkscape:export-xdpi="67.034012"
-   inkscape:export-ydpi="67.034012">
-  <defs
-     id="defs3217" />
-  <sodipodi:namedview
-     id="base"
-     pagecolor="#ffffff"
-     bordercolor="#666666"
-     borderopacity="1.0"
-     inkscape:pageopacity="0.0"
-     inkscape:pageshadow="2"
-     inkscape:zoom="0.98994949"
-     inkscape:cx="159.25688"
-     inkscape:cy="149.8376"
-     inkscape:document-units="mm"
-     inkscape:current-layer="layer1"
-     showgrid="false"
-     inkscape:pagecheckerboard="true"
-     inkscape:window-width="1920"
-     inkscape:window-height="1043"
-     inkscape:window-x="0"
-     inkscape:window-y="0"
-     inkscape:window-maximized="1" />
-  <metadata
-     id="metadata3220">
-    <rdf:RDF>
-      <cc:Work
-         rdf:about="">
-        <dc:format>image/svg+xml</dc:format>
-        <dc:type
-           rdf:resource="http://purl.org/dc/dcmitype/StillImage" />
-        <dc:title></dc:title>
-      </cc:Work>
-    </rdf:RDF>
-  </metadata>
-  <g
-     inkscape:label="Layer 1"
-     inkscape:groupmode="layer"
-     id="layer1"
-     transform="translate(-56.556041,-109.30405)">
-    <g
-       transform="translate(-3.7799155,-23.482217)"
-       id="g2559">
-      <path
-         inkscape:connector-curvature="0"
-         id="path148"
-         style="fill:#e23229;fill-opacity:1;fill-rule:nonzero;stroke:none;stroke-width:0.34773216"
-         d="m 143.44393,145.03077 0.1484,-0.70241 5.14257,-0.35974 -6.23062,29.75753 -0.69199,0.0483 6.08255,-29.05476 z m 1.18682,31.16724 7.31835,-35.07438 -10.43302,0.72923 -1.28514,6.12249 4.45021,-0.31125 -6.03235,28.95253 z" />
-      <path
-         sodipodi:nodetypes="cccccccccccccccccccccc"
-         inkscape:connector-curvature="0"
-         id="path152"
-         style="fill:#e23229;fill-opacity:1;fill-rule:nonzero;stroke:none;stroke-width:0.34773216"
-         d="m 169.25392,142.53363 -3.53672,16.8925 4.79124,-0.32874 -0.15681,0.75402 -4.79234,0.32881 -2.53549,12.11072 -0.75405,0.052 2.53724,-12.11108 -11.37332,0.78724 z m -18.98495,21.327 11.37324,-0.78724 -2.5247,12.11146 5.98312,-0.41839 2.52513,-12.10406 4.82658,-0.33116 1.26721,-6.07903 -4.82564,0.33109 3.52398,-16.89101 -4.56014,0.33565 -16.70168,19.60839 z" />
-      <path
-         inkscape:connector-curvature="0"
-         id="path156"
-         style="fill:#fefefe;fill-opacity:1;fill-rule:nonzero;stroke:none;stroke-width:0.34773216"
-         d="m 88.591903,151.83158 -2.595368,0.18103 0.741705,-3.62685 2.595079,-0.182 z m -4.581719,-6.72375 -3.99857,19.05572 3.468889,-0.24195 1.774487,-8.38766 6.064403,-0.42299 2.224789,-10.66981 z" />
-      <path
-         inkscape:connector-curvature="0"
-         id="path160"
-         style="fill:#fefefe;fill-opacity:1;fill-rule:nonzero;stroke:none;stroke-width:0.34773216"
-         d="m 100.85029,147.82177 2.83371,-0.19837 -0.74166,3.60045 -2.83371,0.19836 z m -6.726869,15.77696 3.469312,-0.24198 1.774487,-8.38695 2.8337,-0.19837 -1.77453,8.38695 3.46938,-0.24296 3.99895,-19.05608 -9.771974,0.68329 z" />
-      <path
-         inkscape:connector-curvature="0"
-         id="path164"
-         style="fill:#fefefe;fill-opacity:1;fill-rule:nonzero;stroke:none;stroke-width:0.34773216"
-         d="m 108.80467,162.68768 9.74554,-0.68118 1.377,-6.50502 -3.4693,0.24296 -0.63527,2.9832 -2.80718,0.19654 2.51548,-12.01379 2.80731,-0.19754 -0.50239,2.4195 3.46902,-0.24294 1.24513,-5.93998 -9.74589,0.68119 z" />
-      <path
-         inkscape:connector-curvature="0"
-         id="path168"
-         style="fill:#fefefe;fill-opacity:1;fill-rule:nonzero;stroke:none;stroke-width:0.34773216"
-         d="m 135.66767,145.61788 0.7409,-3.5211 -8.95132,0.6259 -3.99824,19.0564 8.95097,-0.62626 0.74082,-3.52077 -5.4816,0.383 1.03272,-4.89224 3.78675,-0.26474 0.74189,-3.52113 -3.78675,0.26474 0.74081,-3.6011 z" />
-      <path
-         inkscape:connector-curvature="0"
-         id="path172"
-         style="fill:#d5d5d5;fill-opacity:1;fill-rule:nonzero;stroke:none;stroke-width:0.34773216"
-         d="m 71.070134,172.95255 -4.734664,0.33077 0.57447,-2.73456 2.139294,-0.14973 -0.376241,1.80924 2.595442,-0.18103 0.930868,-4.44332 -7.330114,0.5118 -1.66358,8.00131 4.734672,-0.33077 -0.773014,3.62025 -2.119829,0.1484 0.475696,-2.23174 -2.614982,0.18237 -1.030327,4.86616 7.330104,-0.5118 z" />
-      <path
-         inkscape:connector-curvature="0"
-         id="path176"
-         style="fill:#d5d5d5;fill-opacity:1;fill-rule:nonzero;stroke:none;stroke-width:0.34773216"
-         d="m 74.794828,169.99754 2.496095,-0.17422 -2.436556,11.62085 2.595151,-0.182 2.436903,-11.62086 2.496023,-0.17421 0.554678,-2.63441 -7.587516,0.53064 z" />
-      <path
-         inkscape:connector-curvature="0"
-         id="path180"
-         style="fill:#d5d5d5;fill-opacity:1;fill-rule:nonzero;stroke:none;stroke-width:0.34773216"
-         d="m 87.573322,171.75893 0.554606,-2.69318 2.119754,-0.1484 -0.554978,2.69354 z m 2.832629,8.59803 2.991888,-14.25529 -7.310379,0.51154 -2.99153,14.25493 2.595227,-0.18201 1.327293,-6.27378 2.11968,-0.14839 -1.327288,6.27414 z" />
-      <path
-         inkscape:connector-curvature="0"
-         id="path184"
-         style="fill:#d5d5d5;fill-opacity:1;fill-rule:nonzero;stroke:none;stroke-width:0.34773216"
-         d="m 98.977684,179.78056 2.436926,-11.62086 2.49608,-0.1752 0.55493,-2.63374 -7.587518,0.53065 -0.554634,2.63373 2.495947,-0.17421 -2.436599,11.6212 z" />
-      <path
-         inkscape:connector-curvature="0"
-         id="path188"
-         style="fill:#d5d5d5;fill-opacity:1;fill-rule:nonzero;stroke:none;stroke-width:0.34773216"
-         d="m 104.62426,179.38562 2.5951,-0.18101 2.9915,-14.25528 -2.59522,0.182 z" />
-      <path
-         inkscape:connector-curvature="0"
-         id="path192"
-         style="fill:#d5d5d5;fill-opacity:1;fill-rule:nonzero;stroke:none;stroke-width:0.34773216"
-         d="m 115.73198,167.18138 2.11975,-0.14839 -1.88236,8.98749 -2.11949,0.14838 z m -5.03203,11.80203 7.31001,-0.51042 2.99153,-14.25494 -7.31028,0.51044 z" />
-      <path
-         inkscape:connector-curvature="0"
-         id="path196"
-         style="fill:#d5d5d5;fill-opacity:1;fill-rule:nonzero;stroke:none;stroke-width:0.34773216"
-         d="m 124.08538,178.07141 1.36653,-6.47511 1.18856,6.29603 2.25853,-0.15792 2.99192,-14.25493 -2.59522,0.18201 -1.36734,6.57353 -1.18854,-6.39514 -2.25854,0.15791 -2.99084,14.25493 z" />
-      <path
-         inkscape:connector-curvature="0"
-         id="path200"
-         style="fill:#fefefe;fill-opacity:1;fill-rule:nonzero;stroke:none;stroke-width:0.34773216"
-         d="m 66.677649,158.65784 -1.377018,6.50538 9.798398,-0.68471 2.489415,-11.87958 -6.329111,0.44214 0.767747,-3.65465 2.860076,-0.20018 -0.503204,2.41917 3.469299,-0.24297 1.244526,-5.93996 -4.328229,0.30289 -8.728772,0.56991 2.909827,1.489 -1.87565,9.01912 6.329037,-0.44213 -1.032406,4.83973 -2.833645,0.19738 0.635302,-2.98354 z" />
-      <path
-         inkscape:connector-curvature="0"
-         id="path204"
-         style="fill:#e23229;fill-opacity:1;fill-rule:nonzero;stroke:none;stroke-width:0.34773216"
-         d="m 70.519326,139.92277 -0.277457,1.36553 103.473271,-7.11317 0.29445,-1.38886 z" />
-      <path
-         inkscape:connector-curvature="0"
-         id="path208"
-         style="fill:#e23229;fill-opacity:1;fill-rule:nonzero;stroke:none;stroke-width:0.34773216"
-         d="m 60.335956,189.16626 103.473274,-7.11356 0.29444,-1.38885 -103.489968,7.13649 z" />
-      <path
-         sodipodi:nodetypes="cccccccc"
-         inkscape:connector-curvature="0"
-         id="path1772"
-         d="m 167.92741,145.26275 -12.87687,14.89523 9.91366,-0.68019 z m -3.743,7.27758 -1.02896,4.93612 -3.51544,0.2412 z"
-         style="fill:#e23229;fill-opacity:1;stroke:none;stroke-width:0.2626844px;stroke-linecap:butt;stroke-linejoin:miter;stroke-opacity:1" />
-    </g>
-  </g>
-</svg>

Robust.Analyzers.Tests/AccessAnalyzer_Test.cs

@@ -0,0 +1,822 @@
+using System.Threading.Tasks;
+using Microsoft.CodeAnalysis.CSharp.Testing;
+using Microsoft.CodeAnalysis.Testing;
+using Microsoft.CodeAnalysis.Testing.Verifiers;
+using NUnit.Framework;
+using Robust.Analyzers;
+
+using VerifyCS = Microsoft.CodeAnalysis.CSharp.Testing.NUnit.AnalyzerVerifier<Robust.Analyzers.AccessAnalyzer>;
+using static Microsoft.CodeAnalysis.Testing.DiagnosticResult;
+
+namespace Robust.Analyzers.Tests;
+
+[Parallelizable(ParallelScope.All | ParallelScope.Fixtures)]
+[TestFixture]
+public sealed class AccessAnalyzer_Test
+{
+    public Task Verifier(string code, params DiagnosticResult[] expected)
+    {
+        var test = new CSharpAnalyzerTest<AccessAnalyzer, NUnitVerifier>()
+        {
+            TestState =
+            {
+                AdditionalReferences = { typeof(AccessAnalyzer).Assembly },
+                Sources = { code }
+            },
+        };
+
+        // ExpectedDiagnostics cannot be set, so we need to AddRange here...
+        test.TestState.ExpectedDiagnostics.AddRange(expected);
+
+        return test.RunAsync();
+    }
+
+    /*
+     *
+     */
+
+    [Test]
+    public async Task ReadTest()
+    {
+        const string code = @"
+using System;
+using Robust.Shared.Analyzers;
+// ReSharper disable RedundantAssignment
+// ReSharper disable UnusedVariable
+// ReSharper disable ArrangeThisQualifier
+// ReSharper disable UnusedMember.Global
+// ReSharper disable UnusedType.Global
+
+public struct MyData
+{
+    public int MyField;
+
+    public static bool operator ==(MyData lhs, MyData rhs) => lhs.MyField == rhs.MyField;
+    public static bool operator !=(MyData lhs, MyData rhs) => lhs.MyField != rhs.MyField;
+}
+
+[Access(typeof(FriendlyClass),
+    Self = AccessPermissions.None,
+    Friend = AccessPermissions.None,
+    Other = AccessPermissions.None)]
+public sealed class TypeNobodyCanRead
+{
+    public MyData Data = default;
+
+    [Access(typeof(FriendlyClass),
+        Self = AccessPermissions.Read,
+        Friend = AccessPermissions.Read,
+        Other = AccessPermissions.Read)]
+    public MyData Data2 = default;
+
+    public void TestTypeNobodyCanRead(TypeNobodyCanRead obj)
+    {
+        // None of these accesses should be allowed.
+        var copy = Data;
+        var copy2 = this.Data;
+        var copy3 = obj.Data;
+
+        copy = Data;
+        copy = this.Data;
+        copy = obj.Data;
+
+        var copy4 = Data.MyField;
+        var copy5 = this.Data.MyField;
+        var copy6 = obj.Data.MyField;
+
+        if (Data == copy) {}
+        if (this.Data == copy) {}
+        if (obj.Data == copy) {}
+
+        if(Data.MyField == 0) {}
+        if(this.Data.MyField == 0) {}
+        if(obj.Data.MyField == 0) {}
+
+        // All of these accesses should be fine.
+        var copy7 = Data2;
+        var copy8 = this.Data2;
+        var copy9 = obj.Data2;
+
+        copy = Data2;
+        copy = this.Data2;
+        copy = obj.Data2;
+
+        var copy10 = Data2.MyField;
+        var copy11 = this.Data2.MyField;
+        var copy12 = obj.Data2.MyField;
+
+        if (Data2 == copy) {}
+        if (this.Data2 == copy) {}
+        if (obj.Data2 == copy) {}
+
+        if(Data2.MyField == 0) {}
+        if(this.Data2.MyField == 0) {}
+        if(obj.Data2.MyField == 0) {}
+    }
+}
+
+[Access(typeof(FriendlyClass),
+    Self = AccessPermissions.Read,
+    Friend = AccessPermissions.Read,
+    Other = AccessPermissions.Read)]
+public sealed class MemberNobodyCanRead
+{
+    [Access(typeof(FriendlyClass),
+        Self = AccessPermissions.None,
+        Friend = AccessPermissions.None,
+        Other = AccessPermissions.None)]
+    public MyData Data = default;
+
+    public MyData Data2 = default;
+
+    public void TestMemberNobodyCanRead(TypeNobodyCanRead obj)
+    {
+        // None of these accesses should be allowed.
+        var copy = Data;
+        var copy2 = this.Data;
+        var copy3 = obj.Data;
+
+        copy = Data;
+        copy = this.Data;
+        copy = obj.Data;
+
+        var copy4 = Data.MyField;
+        var copy5 = this.Data.MyField;
+        var copy6 = obj.Data.MyField;
+
+        if (Data == copy) {}
+        if (this.Data == copy) {}
+        if (obj.Data == copy) {}
+
+        if(Data.MyField == 0) {}
+        if(this.Data.MyField == 0) {}
+        if(obj.Data.MyField == 0) {}
+
+        // All of these accesses should be fine.
+        var copy7 = Data2;
+        var copy8 = this.Data2;
+        var copy9 = obj.Data2;
+
+        copy = Data2;
+        copy = this.Data2;
+        copy = obj.Data2;
+
+        var copy10 = Data2.MyField;
+        var copy11 = this.Data2.MyField;
+        var copy12 = obj.Data2.MyField;
+
+        if (Data2 == copy) {}
+        if (this.Data2 == copy) {}
+        if (obj.Data2 == copy) {}
+
+        if(Data2.MyField == 0) {}
+        if(this.Data2.MyField == 0) {}
+        if(obj.Data2.MyField == 0) {}
+    }
+}
+
+public sealed class FriendlyClass
+{
+    public void TestTypeNobodyCanRead(TypeNobodyCanRead obj)
+    {
+        // We shouldn't be able to access any of these, even if we're a friend..
+        var copy = obj.Data;
+        copy = obj.Data;
+
+        var copy2 = obj.Data.MyField;
+        copy2 = obj.Data.MyField;
+
+        if (obj.Data == copy) {}
+        if(obj.Data.MyField == 0) {}
+
+        // We should be allowed to access all of these, we're friends!
+        var copy3 = obj.Data2;
+        copy = obj.Data2;
+
+        var copy4 = obj.Data2.MyField;
+        copy4 = obj.Data2.MyField;
+
+        if(obj.Data2 == copy) {}
+        if(obj.Data2.MyField == 0) {}
+    }
+
+    public void TestMemberNobodyCanRead(MemberNobodyCanRead obj)
+    {
+        // We shouldn't be able to access any of these, even if we're a friend..
+        var copy = obj.Data;
+        copy = obj.Data;
+
+        var copy2 = obj.Data.MyField;
+        copy2 = obj.Data.MyField;
+
+        if (obj.Data == copy) {}
+        if(obj.Data.MyField == 0) {}
+
+        // We should be allowed to access all of these, we're friends!
+        var copy3 = obj.Data2;
+        copy = obj.Data2;
+
+        var copy4 = obj.Data2.MyField;
+        copy4 = obj.Data2.MyField;
+
+        if(obj.Data2 == copy) {}
+        if(obj.Data2.MyField == 0) {}
+    }
+}
+
+public sealed class OtherClass
+{
+    public void TestTypeNobodyCanRead(TypeNobodyCanRead obj)
+    {
+        // We shouldn't be able to access any of these, as 'other types' can't..
+        var copy = obj.Data;
+        copy = obj.Data;
+
+        var copy2 = obj.Data.MyField;
+        copy2 = obj.Data.MyField;
+
+        if (obj.Data == copy) {}
+        if(obj.Data.MyField == 0) {}
+
+        // We should be allowed to access all of these, they let others read it!
+        var copy3 = obj.Data2;
+        copy = obj.Data2;
+
+        var copy4 = obj.Data2.MyField;
+        copy4 = obj.Data2.MyField;
+
+        if(obj.Data2 == copy) {}
+        if(obj.Data2.MyField == 0) {}
+    }
+
+    public void TestMemberNobodyCanRead(MemberNobodyCanRead obj)
+    {
+        // We shouldn't be able to access any of these, as 'other types' can't..
+        var copy = obj.Data;
+        copy = obj.Data;
+
+        var copy2 = obj.Data.MyField;
+        copy2 = obj.Data.MyField;
+
+        if (obj.Data == copy) {}
+        if(obj.Data.MyField == 0) {}
+
+        // We should be allowed to access all of these, they let others read it!
+        var copy3 = obj.Data2;
+        copy = obj.Data2;
+
+        var copy4 = obj.Data2.MyField;
+        copy4 = obj.Data2.MyField;
+
+        if(obj.Data2 == copy) {}
+        if(obj.Data2.MyField == 0) {}
+    }
+}";
+
+        await Verifier(code,
+            // AUTO-GENERATED DIAGNOSTICS BELOW //
+// /0/Test0.cs(35,20): error RA0002: Tried to perform a 'Read' same-type access to member 'Data' in type 'TypeNobodyCanRead', despite having no access. Type Permissions: ---------
+VerifyCS.Diagnostic().WithSpan(35, 20, 35, 24).WithArguments("a 'Read' same-type", "Data", "TypeNobodyCanRead", "having no", "Type Permissions: ---------"),
+// /0/Test0.cs(36,21): error RA0002: Tried to perform a 'Read' same-type access to member 'Data' in type 'TypeNobodyCanRead', despite having no access. Type Permissions: ---------
+VerifyCS.Diagnostic().WithSpan(36, 21, 36, 30).WithArguments("a 'Read' same-type", "Data", "TypeNobodyCanRead", "having no", "Type Permissions: ---------"),
+// /0/Test0.cs(37,21): error RA0002: Tried to perform a 'Read' same-type access to member 'Data' in type 'TypeNobodyCanRead', despite having no access. Type Permissions: ---------
+VerifyCS.Diagnostic().WithSpan(37, 21, 37, 29).WithArguments("a 'Read' same-type", "Data", "TypeNobodyCanRead", "having no", "Type Permissions: ---------"),
+// /0/Test0.cs(39,16): error RA0002: Tried to perform a 'Read' same-type access to member 'Data' in type 'TypeNobodyCanRead', despite having no access. Type Permissions: ---------
+VerifyCS.Diagnostic().WithSpan(39, 16, 39, 20).WithArguments("a 'Read' same-type", "Data", "TypeNobodyCanRead", "having no", "Type Permissions: ---------"),
+// /0/Test0.cs(40,16): error RA0002: Tried to perform a 'Read' same-type access to member 'Data' in type 'TypeNobodyCanRead', despite having no access. Type Permissions: ---------
+VerifyCS.Diagnostic().WithSpan(40, 16, 40, 25).WithArguments("a 'Read' same-type", "Data", "TypeNobodyCanRead", "having no", "Type Permissions: ---------"),
+// /0/Test0.cs(41,16): error RA0002: Tried to perform a 'Read' same-type access to member 'Data' in type 'TypeNobodyCanRead', despite having no access. Type Permissions: ---------
+VerifyCS.Diagnostic().WithSpan(41, 16, 41, 24).WithArguments("a 'Read' same-type", "Data", "TypeNobodyCanRead", "having no", "Type Permissions: ---------"),
+// /0/Test0.cs(43,21): error RA0002: Tried to perform a 'Read' same-type access to member 'Data' in type 'TypeNobodyCanRead', despite having no access. Type Permissions: ---------
+VerifyCS.Diagnostic().WithSpan(43, 21, 43, 25).WithArguments("a 'Read' same-type", "Data", "TypeNobodyCanRead", "having no", "Type Permissions: ---------"),
+// /0/Test0.cs(44,21): error RA0002: Tried to perform a 'Read' same-type access to member 'Data' in type 'TypeNobodyCanRead', despite having no access. Type Permissions: ---------
+VerifyCS.Diagnostic().WithSpan(44, 21, 44, 30).WithArguments("a 'Read' same-type", "Data", "TypeNobodyCanRead", "having no", "Type Permissions: ---------"),
+// /0/Test0.cs(45,21): error RA0002: Tried to perform a 'Read' same-type access to member 'Data' in type 'TypeNobodyCanRead', despite having no access. Type Permissions: ---------
+VerifyCS.Diagnostic().WithSpan(45, 21, 45, 29).WithArguments("a 'Read' same-type", "Data", "TypeNobodyCanRead", "having no", "Type Permissions: ---------"),
+// /0/Test0.cs(47,13): error RA0002: Tried to perform a 'Read' same-type access to member 'Data' in type 'TypeNobodyCanRead', despite having no access. Type Permissions: ---------
+VerifyCS.Diagnostic().WithSpan(47, 13, 47, 17).WithArguments("a 'Read' same-type", "Data", "TypeNobodyCanRead", "having no", "Type Permissions: ---------"),
+// /0/Test0.cs(48,13): error RA0002: Tried to perform a 'Read' same-type access to member 'Data' in type 'TypeNobodyCanRead', despite having no access. Type Permissions: ---------
+VerifyCS.Diagnostic().WithSpan(48, 13, 48, 22).WithArguments("a 'Read' same-type", "Data", "TypeNobodyCanRead", "having no", "Type Permissions: ---------"),
+// /0/Test0.cs(49,13): error RA0002: Tried to perform a 'Read' same-type access to member 'Data' in type 'TypeNobodyCanRead', despite having no access. Type Permissions: ---------
+VerifyCS.Diagnostic().WithSpan(49, 13, 49, 21).WithArguments("a 'Read' same-type", "Data", "TypeNobodyCanRead", "having no", "Type Permissions: ---------"),
+// /0/Test0.cs(51,12): error RA0002: Tried to perform a 'Read' same-type access to member 'Data' in type 'TypeNobodyCanRead', despite having no access. Type Permissions: ---------
+VerifyCS.Diagnostic().WithSpan(51, 12, 51, 16).WithArguments("a 'Read' same-type", "Data", "TypeNobodyCanRead", "having no", "Type Permissions: ---------"),
+// /0/Test0.cs(52,12): error RA0002: Tried to perform a 'Read' same-type access to member 'Data' in type 'TypeNobodyCanRead', despite having no access. Type Permissions: ---------
+VerifyCS.Diagnostic().WithSpan(52, 12, 52, 21).WithArguments("a 'Read' same-type", "Data", "TypeNobodyCanRead", "having no", "Type Permissions: ---------"),
+// /0/Test0.cs(53,12): error RA0002: Tried to perform a 'Read' same-type access to member 'Data' in type 'TypeNobodyCanRead', despite having no access. Type Permissions: ---------
+VerifyCS.Diagnostic().WithSpan(53, 12, 53, 20).WithArguments("a 'Read' same-type", "Data", "TypeNobodyCanRead", "having no", "Type Permissions: ---------"),
+// /0/Test0.cs(95,20): error RA0002: Tried to perform a 'Read' same-type access to member 'Data' in type 'MemberNobodyCanRead', despite having no access. Member Permissions: ---------
+VerifyCS.Diagnostic().WithSpan(95, 20, 95, 24).WithArguments("a 'Read' same-type", "Data", "MemberNobodyCanRead", "having no", "Member Permissions: ---------"),
+// /0/Test0.cs(96,21): error RA0002: Tried to perform a 'Read' same-type access to member 'Data' in type 'MemberNobodyCanRead', despite having no access. Member Permissions: ---------
+VerifyCS.Diagnostic().WithSpan(96, 21, 96, 30).WithArguments("a 'Read' same-type", "Data", "MemberNobodyCanRead", "having no", "Member Permissions: ---------"),
+// /0/Test0.cs(97,21): error RA0002: Tried to perform a 'Read' other-type access to member 'Data' in type 'TypeNobodyCanRead', despite having no access. Type Permissions: ---------
+VerifyCS.Diagnostic().WithSpan(97, 21, 97, 29).WithArguments("a 'Read' other-type", "Data", "TypeNobodyCanRead", "having no", "Type Permissions: ---------"),
+// /0/Test0.cs(99,16): error RA0002: Tried to perform a 'Read' same-type access to member 'Data' in type 'MemberNobodyCanRead', despite having no access. Member Permissions: ---------
+VerifyCS.Diagnostic().WithSpan(99, 16, 99, 20).WithArguments("a 'Read' same-type", "Data", "MemberNobodyCanRead", "having no", "Member Permissions: ---------"),
+// /0/Test0.cs(100,16): error RA0002: Tried to perform a 'Read' same-type access to member 'Data' in type 'MemberNobodyCanRead', despite having no access. Member Permissions: ---------
+VerifyCS.Diagnostic().WithSpan(100, 16, 100, 25).WithArguments("a 'Read' same-type", "Data", "MemberNobodyCanRead", "having no", "Member Permissions: ---------"),
+// /0/Test0.cs(101,16): error RA0002: Tried to perform a 'Read' other-type access to member 'Data' in type 'TypeNobodyCanRead', despite having no access. Type Permissions: ---------
+VerifyCS.Diagnostic().WithSpan(101, 16, 101, 24).WithArguments("a 'Read' other-type", "Data", "TypeNobodyCanRead", "having no", "Type Permissions: ---------"),
+// /0/Test0.cs(103,21): error RA0002: Tried to perform a 'Read' same-type access to member 'Data' in type 'MemberNobodyCanRead', despite having no access. Member Permissions: ---------
+VerifyCS.Diagnostic().WithSpan(103, 21, 103, 25).WithArguments("a 'Read' same-type", "Data", "MemberNobodyCanRead", "having no", "Member Permissions: ---------"),
+// /0/Test0.cs(104,21): error RA0002: Tried to perform a 'Read' same-type access to member 'Data' in type 'MemberNobodyCanRead', despite having no access. Member Permissions: ---------
+VerifyCS.Diagnostic().WithSpan(104, 21, 104, 30).WithArguments("a 'Read' same-type", "Data", "MemberNobodyCanRead", "having no", "Member Permissions: ---------"),
+// /0/Test0.cs(105,21): error RA0002: Tried to perform a 'Read' other-type access to member 'Data' in type 'TypeNobodyCanRead', despite having no access. Type Permissions: ---------
+VerifyCS.Diagnostic().WithSpan(105, 21, 105, 29).WithArguments("a 'Read' other-type", "Data", "TypeNobodyCanRead", "having no", "Type Permissions: ---------"),
+// /0/Test0.cs(107,13): error RA0002: Tried to perform a 'Read' same-type access to member 'Data' in type 'MemberNobodyCanRead', despite having no access. Member Permissions: ---------
+VerifyCS.Diagnostic().WithSpan(107, 13, 107, 17).WithArguments("a 'Read' same-type", "Data", "MemberNobodyCanRead", "having no", "Member Permissions: ---------"),
+// /0/Test0.cs(108,13): error RA0002: Tried to perform a 'Read' same-type access to member 'Data' in type 'MemberNobodyCanRead', despite having no access. Member Permissions: ---------
+VerifyCS.Diagnostic().WithSpan(108, 13, 108, 22).WithArguments("a 'Read' same-type", "Data", "MemberNobodyCanRead", "having no", "Member Permissions: ---------"),
+// /0/Test0.cs(109,13): error RA0002: Tried to perform a 'Read' other-type access to member 'Data' in type 'TypeNobodyCanRead', despite having no access. Type Permissions: ---------
+VerifyCS.Diagnostic().WithSpan(109, 13, 109, 21).WithArguments("a 'Read' other-type", "Data", "TypeNobodyCanRead", "having no", "Type Permissions: ---------"),
+// /0/Test0.cs(111,12): error RA0002: Tried to perform a 'Read' same-type access to member 'Data' in type 'MemberNobodyCanRead', despite having no access. Member Permissions: ---------
+VerifyCS.Diagnostic().WithSpan(111, 12, 111, 16).WithArguments("a 'Read' same-type", "Data", "MemberNobodyCanRead", "having no", "Member Permissions: ---------"),
+// /0/Test0.cs(112,12): error RA0002: Tried to perform a 'Read' same-type access to member 'Data' in type 'MemberNobodyCanRead', despite having no access. Member Permissions: ---------
+VerifyCS.Diagnostic().WithSpan(112, 12, 112, 21).WithArguments("a 'Read' same-type", "Data", "MemberNobodyCanRead", "having no", "Member Permissions: ---------"),
+// /0/Test0.cs(113,12): error RA0002: Tried to perform a 'Read' other-type access to member 'Data' in type 'TypeNobodyCanRead', despite having no access. Type Permissions: ---------
+VerifyCS.Diagnostic().WithSpan(113, 12, 113, 20).WithArguments("a 'Read' other-type", "Data", "TypeNobodyCanRead", "having no", "Type Permissions: ---------"),
+// /0/Test0.cs(143,20): error RA0002: Tried to perform a 'Read' friend-type access to member 'Data' in type 'TypeNobodyCanRead', despite having no access. Type Permissions: ---------
+VerifyCS.Diagnostic().WithSpan(143, 20, 143, 28).WithArguments("a 'Read' friend-type", "Data", "TypeNobodyCanRead", "having no", "Type Permissions: ---------"),
+// /0/Test0.cs(144,16): error RA0002: Tried to perform a 'Read' friend-type access to member 'Data' in type 'TypeNobodyCanRead', despite having no access. Type Permissions: ---------
+VerifyCS.Diagnostic().WithSpan(144, 16, 144, 24).WithArguments("a 'Read' friend-type", "Data", "TypeNobodyCanRead", "having no", "Type Permissions: ---------"),
+// /0/Test0.cs(146,21): error RA0002: Tried to perform a 'Read' friend-type access to member 'Data' in type 'TypeNobodyCanRead', despite having no access. Type Permissions: ---------
+VerifyCS.Diagnostic().WithSpan(146, 21, 146, 29).WithArguments("a 'Read' friend-type", "Data", "TypeNobodyCanRead", "having no", "Type Permissions: ---------"),
+// /0/Test0.cs(147,17): error RA0002: Tried to perform a 'Read' friend-type access to member 'Data' in type 'TypeNobodyCanRead', despite having no access. Type Permissions: ---------
+VerifyCS.Diagnostic().WithSpan(147, 17, 147, 25).WithArguments("a 'Read' friend-type", "Data", "TypeNobodyCanRead", "having no", "Type Permissions: ---------"),
+// /0/Test0.cs(149,13): error RA0002: Tried to perform a 'Read' friend-type access to member 'Data' in type 'TypeNobodyCanRead', despite having no access. Type Permissions: ---------
+VerifyCS.Diagnostic().WithSpan(149, 13, 149, 21).WithArguments("a 'Read' friend-type", "Data", "TypeNobodyCanRead", "having no", "Type Permissions: ---------"),
+// /0/Test0.cs(150,12): error RA0002: Tried to perform a 'Read' friend-type access to member 'Data' in type 'TypeNobodyCanRead', despite having no access. Type Permissions: ---------
+VerifyCS.Diagnostic().WithSpan(150, 12, 150, 20).WithArguments("a 'Read' friend-type", "Data", "TypeNobodyCanRead", "having no", "Type Permissions: ---------"),
+// /0/Test0.cs(166,20): error RA0002: Tried to perform a 'Read' friend-type access to member 'Data' in type 'MemberNobodyCanRead', despite having no access. Member Permissions: ---------
+VerifyCS.Diagnostic().WithSpan(166, 20, 166, 28).WithArguments("a 'Read' friend-type", "Data", "MemberNobodyCanRead", "having no", "Member Permissions: ---------"),
+// /0/Test0.cs(167,16): error RA0002: Tried to perform a 'Read' friend-type access to member 'Data' in type 'MemberNobodyCanRead', despite having no access. Member Permissions: ---------
+VerifyCS.Diagnostic().WithSpan(167, 16, 167, 24).WithArguments("a 'Read' friend-type", "Data", "MemberNobodyCanRead", "having no", "Member Permissions: ---------"),
+// /0/Test0.cs(169,21): error RA0002: Tried to perform a 'Read' friend-type access to member 'Data' in type 'MemberNobodyCanRead', despite having no access. Member Permissions: ---------
+VerifyCS.Diagnostic().WithSpan(169, 21, 169, 29).WithArguments("a 'Read' friend-type", "Data", "MemberNobodyCanRead", "having no", "Member Permissions: ---------"),
+// /0/Test0.cs(170,17): error RA0002: Tried to perform a 'Read' friend-type access to member 'Data' in type 'MemberNobodyCanRead', despite having no access. Member Permissions: ---------
+VerifyCS.Diagnostic().WithSpan(170, 17, 170, 25).WithArguments("a 'Read' friend-type", "Data", "MemberNobodyCanRead", "having no", "Member Permissions: ---------"),
+// /0/Test0.cs(172,13): error RA0002: Tried to perform a 'Read' friend-type access to member 'Data' in type 'MemberNobodyCanRead', despite having no access. Member Permissions: ---------
+VerifyCS.Diagnostic().WithSpan(172, 13, 172, 21).WithArguments("a 'Read' friend-type", "Data", "MemberNobodyCanRead", "having no", "Member Permissions: ---------"),
+// /0/Test0.cs(173,12): error RA0002: Tried to perform a 'Read' friend-type access to member 'Data' in type 'MemberNobodyCanRead', despite having no access. Member Permissions: ---------
+VerifyCS.Diagnostic().WithSpan(173, 12, 173, 20).WithArguments("a 'Read' friend-type", "Data", "MemberNobodyCanRead", "having no", "Member Permissions: ---------"),
+// /0/Test0.cs(192,20): error RA0002: Tried to perform a 'Read' other-type access to member 'Data' in type 'TypeNobodyCanRead', despite having no access. Type Permissions: ---------
+VerifyCS.Diagnostic().WithSpan(192, 20, 192, 28).WithArguments("a 'Read' other-type", "Data", "TypeNobodyCanRead", "having no", "Type Permissions: ---------"),
+// /0/Test0.cs(193,16): error RA0002: Tried to perform a 'Read' other-type access to member 'Data' in type 'TypeNobodyCanRead', despite having no access. Type Permissions: ---------
+VerifyCS.Diagnostic().WithSpan(193, 16, 193, 24).WithArguments("a 'Read' other-type", "Data", "TypeNobodyCanRead", "having no", "Type Permissions: ---------"),
+// /0/Test0.cs(195,21): error RA0002: Tried to perform a 'Read' other-type access to member 'Data' in type 'TypeNobodyCanRead', despite having no access. Type Permissions: ---------
+VerifyCS.Diagnostic().WithSpan(195, 21, 195, 29).WithArguments("a 'Read' other-type", "Data", "TypeNobodyCanRead", "having no", "Type Permissions: ---------"),
+// /0/Test0.cs(196,17): error RA0002: Tried to perform a 'Read' other-type access to member 'Data' in type 'TypeNobodyCanRead', despite having no access. Type Permissions: ---------
+VerifyCS.Diagnostic().WithSpan(196, 17, 196, 25).WithArguments("a 'Read' other-type", "Data", "TypeNobodyCanRead", "having no", "Type Permissions: ---------"),
+// /0/Test0.cs(198,13): error RA0002: Tried to perform a 'Read' other-type access to member 'Data' in type 'TypeNobodyCanRead', despite having no access. Type Permissions: ---------
+VerifyCS.Diagnostic().WithSpan(198, 13, 198, 21).WithArguments("a 'Read' other-type", "Data", "TypeNobodyCanRead", "having no", "Type Permissions: ---------"),
+// /0/Test0.cs(199,12): error RA0002: Tried to perform a 'Read' other-type access to member 'Data' in type 'TypeNobodyCanRead', despite having no access. Type Permissions: ---------
+VerifyCS.Diagnostic().WithSpan(199, 12, 199, 20).WithArguments("a 'Read' other-type", "Data", "TypeNobodyCanRead", "having no", "Type Permissions: ---------"),
+// /0/Test0.cs(215,20): error RA0002: Tried to perform a 'Read' other-type access to member 'Data' in type 'MemberNobodyCanRead', despite having no access. Member Permissions: ---------
+VerifyCS.Diagnostic().WithSpan(215, 20, 215, 28).WithArguments("a 'Read' other-type", "Data", "MemberNobodyCanRead", "having no", "Member Permissions: ---------"),
+// /0/Test0.cs(216,16): error RA0002: Tried to perform a 'Read' other-type access to member 'Data' in type 'MemberNobodyCanRead', despite having no access. Member Permissions: ---------
+VerifyCS.Diagnostic().WithSpan(216, 16, 216, 24).WithArguments("a 'Read' other-type", "Data", "MemberNobodyCanRead", "having no", "Member Permissions: ---------"),
+// /0/Test0.cs(218,21): error RA0002: Tried to perform a 'Read' other-type access to member 'Data' in type 'MemberNobodyCanRead', despite having no access. Member Permissions: ---------
+VerifyCS.Diagnostic().WithSpan(218, 21, 218, 29).WithArguments("a 'Read' other-type", "Data", "MemberNobodyCanRead", "having no", "Member Permissions: ---------"),
+// /0/Test0.cs(219,17): error RA0002: Tried to perform a 'Read' other-type access to member 'Data' in type 'MemberNobodyCanRead', despite having no access. Member Permissions: ---------
+VerifyCS.Diagnostic().WithSpan(219, 17, 219, 25).WithArguments("a 'Read' other-type", "Data", "MemberNobodyCanRead", "having no", "Member Permissions: ---------"),
+// /0/Test0.cs(221,13): error RA0002: Tried to perform a 'Read' other-type access to member 'Data' in type 'MemberNobodyCanRead', despite having no access. Member Permissions: ---------
+VerifyCS.Diagnostic().WithSpan(221, 13, 221, 21).WithArguments("a 'Read' other-type", "Data", "MemberNobodyCanRead", "having no", "Member Permissions: ---------"),
+// /0/Test0.cs(222,12): error RA0002: Tried to perform a 'Read' other-type access to member 'Data' in type 'MemberNobodyCanRead', despite having no access. Member Permissions: ---------
+VerifyCS.Diagnostic().WithSpan(222, 12, 222, 20).WithArguments("a 'Read' other-type", "Data", "MemberNobodyCanRead", "having no", "Member Permissions: ---------")
+            );
+    }
+
+    [Test]
+    public async Task WriteTest()
+    {
+        const string code = @"
+using System;
+using Robust.Shared.Analyzers;
+// ReSharper disable RedundantAssignment
+// ReSharper disable UnusedVariable
+// ReSharper disable ArrangeThisQualifier
+// ReSharper disable UnusedMember.Global
+// ReSharper disable UnusedType.Global
+// ReSharper disable NotAccessedField.Global
+// ReSharper disable RedundantDefaultMemberInitializer
+
+public struct MyData
+{
+    public int MyField;
+}
+
+[Access(typeof(FriendlyClass),
+    Self = AccessPermissions.None,
+    Friend = AccessPermissions.None,
+    Other = AccessPermissions.None)]
+public sealed class TypeNobodyCanWrite
+{
+    public MyData Data = default;
+
+    [Access(typeof(FriendlyClass),
+        Self = AccessPermissions.Write,
+        Friend = AccessPermissions.Write,
+        Other = AccessPermissions.Write)]
+    public MyData Data2 = default;
+
+    public void TestTypeNobodyCanWrite(TypeNobodyCanWrite obj)
+    {
+        // None of these accesses should be allowed.
+        Data = default;
+        this.Data = default;
+        obj.Data = default;
+
+        Data.MyField = 0;
+        this.Data.MyField = 0;
+        obj.Data.MyField = 0;
+
+        // All of these accesses should be fine.
+        Data2 = default;
+        this.Data2 = default;
+        obj.Data2 = default;
+
+        Data2.MyField = 0;
+        this.Data2.MyField = 0;
+        obj.Data2.MyField = 0;
+    }
+}
+
+[Access(typeof(FriendlyClass),
+    Self = AccessPermissions.Write,
+    Friend = AccessPermissions.Write,
+    Other = AccessPermissions.Write)]
+public sealed class MemberNobodyCanWrite
+{
+    [Access(typeof(FriendlyClass),
+        Self = AccessPermissions.None,
+        Friend = AccessPermissions.None,
+        Other = AccessPermissions.None)]
+    public MyData Data = default;
+
+    public MyData Data2 = default;
+
+    public void TestMemberNobodyCanWrite(TypeNobodyCanWrite obj)
+    {
+        // None of these accesses should be allowed.
+        Data = default;
+        this.Data = default;
+        obj.Data = default;
+
+        Data.MyField = 0;
+        this.Data.MyField = 0;
+        obj.Data.MyField = 0;
+
+        // All of these accesses should be fine.
+        Data2 = default;
+        this.Data2 = default;
+        obj.Data2 = default;
+
+        Data2.MyField = 0;
+        this.Data2.MyField = 0;
+        obj.Data2.MyField = 0;
+    }
+}
+
+public sealed class FriendlyClass
+{
+    public void TestTypeNobodyCanWrite(TypeNobodyCanWrite obj)
+    {
+        // We shouldn't be able to access any of these, even if we're a friend..
+        obj.Data = default;
+        obj.Data.MyField = 0;
+
+        // We should be allowed to access all of these, we're friends!
+        obj.Data2 = default;
+        obj.Data2.MyField = 0;
+    }
+
+    public void TestMemberNobodyCanWrite(MemberNobodyCanWrite obj)
+    {
+        // We shouldn't be able to access any of these, even if we're a friend..
+        obj.Data = default;
+        obj.Data.MyField = 0;
+
+        // We should be allowed to access all of these, we're friends!
+        obj.Data2 = default;
+        obj.Data2.MyField = 0;
+    }
+}
+
+public sealed class OtherClass
+{
+    public void TestTypeNobodyCanWrite(TypeNobodyCanWrite obj)
+    {
+        // We shouldn't be able to access any of these, as 'other types' can't..
+        obj.Data = default;
+        obj.Data.MyField = 0;
+
+        // We should be allowed to access all of these, they let others write!
+        obj.Data2 = default;
+        obj.Data2.MyField = 0;
+    }
+
+    public void TestMemberNobodyCanWrite(MemberNobodyCanWrite obj)
+    {
+        // We shouldn't be able to access any of these, as 'other types' can't..
+        obj.Data = default;
+        obj.Data.MyField = 0;
+
+        // We should be allowed to access all of these, they let others write!
+        obj.Data2 = default;
+        obj.Data2.MyField = 0;
+    }
+}";
+
+        await Verifier(code,
+            // AUTO-GENERATED DIAGNOSTICS BELOW //
+// /0/Test0.cs(34,9): error RA0002: Tried to perform a 'Write' same-type access to member 'Data' in type 'TypeNobodyCanWrite', despite having no access. Type Permissions: ---------
+VerifyCS.Diagnostic().WithSpan(34, 9, 34, 13).WithArguments("a 'Write' same-type", "Data", "TypeNobodyCanWrite", "having no", "Type Permissions: ---------"),
+// /0/Test0.cs(35,9): error RA0002: Tried to perform a 'Write' same-type access to member 'Data' in type 'TypeNobodyCanWrite', despite having no access. Type Permissions: ---------
+VerifyCS.Diagnostic().WithSpan(35, 9, 35, 18).WithArguments("a 'Write' same-type", "Data", "TypeNobodyCanWrite", "having no", "Type Permissions: ---------"),
+// /0/Test0.cs(36,9): error RA0002: Tried to perform a 'Write' same-type access to member 'Data' in type 'TypeNobodyCanWrite', despite having no access. Type Permissions: ---------
+VerifyCS.Diagnostic().WithSpan(36, 9, 36, 17).WithArguments("a 'Write' same-type", "Data", "TypeNobodyCanWrite", "having no", "Type Permissions: ---------"),
+// /0/Test0.cs(38,9): error RA0002: Tried to perform a 'Write' same-type access to member 'Data' in type 'TypeNobodyCanWrite', despite having no access. Type Permissions: ---------
+VerifyCS.Diagnostic().WithSpan(38, 9, 38, 13).WithArguments("a 'Write' same-type", "Data", "TypeNobodyCanWrite", "having no", "Type Permissions: ---------"),
+// /0/Test0.cs(39,9): error RA0002: Tried to perform a 'Write' same-type access to member 'Data' in type 'TypeNobodyCanWrite', despite having no access. Type Permissions: ---------
+VerifyCS.Diagnostic().WithSpan(39, 9, 39, 18).WithArguments("a 'Write' same-type", "Data", "TypeNobodyCanWrite", "having no", "Type Permissions: ---------"),
+// /0/Test0.cs(40,9): error RA0002: Tried to perform a 'Write' same-type access to member 'Data' in type 'TypeNobodyCanWrite', despite having no access. Type Permissions: ---------
+VerifyCS.Diagnostic().WithSpan(40, 9, 40, 17).WithArguments("a 'Write' same-type", "Data", "TypeNobodyCanWrite", "having no", "Type Permissions: ---------"),
+// /0/Test0.cs(70,9): error RA0002: Tried to perform a 'Write' same-type access to member 'Data' in type 'MemberNobodyCanWrite', despite having no access. Member Permissions: ---------
+VerifyCS.Diagnostic().WithSpan(70, 9, 70, 13).WithArguments("a 'Write' same-type", "Data", "MemberNobodyCanWrite", "having no", "Member Permissions: ---------"),
+// /0/Test0.cs(71,9): error RA0002: Tried to perform a 'Write' same-type access to member 'Data' in type 'MemberNobodyCanWrite', despite having no access. Member Permissions: ---------
+VerifyCS.Diagnostic().WithSpan(71, 9, 71, 18).WithArguments("a 'Write' same-type", "Data", "MemberNobodyCanWrite", "having no", "Member Permissions: ---------"),
+// /0/Test0.cs(72,9): error RA0002: Tried to perform a 'Write' other-type access to member 'Data' in type 'TypeNobodyCanWrite', despite having no access. Type Permissions: ---------
+VerifyCS.Diagnostic().WithSpan(72, 9, 72, 17).WithArguments("a 'Write' other-type", "Data", "TypeNobodyCanWrite", "having no", "Type Permissions: ---------"),
+// /0/Test0.cs(74,9): error RA0002: Tried to perform a 'Write' same-type access to member 'Data' in type 'MemberNobodyCanWrite', despite having no access. Member Permissions: ---------
+VerifyCS.Diagnostic().WithSpan(74, 9, 74, 13).WithArguments("a 'Write' same-type", "Data", "MemberNobodyCanWrite", "having no", "Member Permissions: ---------"),
+// /0/Test0.cs(75,9): error RA0002: Tried to perform a 'Write' same-type access to member 'Data' in type 'MemberNobodyCanWrite', despite having no access. Member Permissions: ---------
+VerifyCS.Diagnostic().WithSpan(75, 9, 75, 18).WithArguments("a 'Write' same-type", "Data", "MemberNobodyCanWrite", "having no", "Member Permissions: ---------"),
+// /0/Test0.cs(76,9): error RA0002: Tried to perform a 'Write' other-type access to member 'Data' in type 'TypeNobodyCanWrite', despite having no access. Type Permissions: ---------
+VerifyCS.Diagnostic().WithSpan(76, 9, 76, 17).WithArguments("a 'Write' other-type", "Data", "TypeNobodyCanWrite", "having no", "Type Permissions: ---------"),
+// /0/Test0.cs(94,9): error RA0002: Tried to perform a 'Write' friend-type access to member 'Data' in type 'TypeNobodyCanWrite', despite having no access. Type Permissions: ---------
+VerifyCS.Diagnostic().WithSpan(94, 9, 94, 17).WithArguments("a 'Write' friend-type", "Data", "TypeNobodyCanWrite", "having no", "Type Permissions: ---------"),
+// /0/Test0.cs(95,9): error RA0002: Tried to perform a 'Write' friend-type access to member 'Data' in type 'TypeNobodyCanWrite', despite having no access. Type Permissions: ---------
+VerifyCS.Diagnostic().WithSpan(95, 9, 95, 17).WithArguments("a 'Write' friend-type", "Data", "TypeNobodyCanWrite", "having no", "Type Permissions: ---------"),
+// /0/Test0.cs(105,9): error RA0002: Tried to perform a 'Write' friend-type access to member 'Data' in type 'MemberNobodyCanWrite', despite having no access. Member Permissions: ---------
+VerifyCS.Diagnostic().WithSpan(105, 9, 105, 17).WithArguments("a 'Write' friend-type", "Data", "MemberNobodyCanWrite", "having no", "Member Permissions: ---------"),
+// /0/Test0.cs(106,9): error RA0002: Tried to perform a 'Write' friend-type access to member 'Data' in type 'MemberNobodyCanWrite', despite having no access. Member Permissions: ---------
+VerifyCS.Diagnostic().WithSpan(106, 9, 106, 17).WithArguments("a 'Write' friend-type", "Data", "MemberNobodyCanWrite", "having no", "Member Permissions: ---------"),
+// /0/Test0.cs(119,9): error RA0002: Tried to perform a 'Write' other-type access to member 'Data' in type 'TypeNobodyCanWrite', despite having no access. Type Permissions: ---------
+VerifyCS.Diagnostic().WithSpan(119, 9, 119, 17).WithArguments("a 'Write' other-type", "Data", "TypeNobodyCanWrite", "having no", "Type Permissions: ---------"),
+// /0/Test0.cs(120,9): error RA0002: Tried to perform a 'Write' other-type access to member 'Data' in type 'TypeNobodyCanWrite', despite having no access. Type Permissions: ---------
+VerifyCS.Diagnostic().WithSpan(120, 9, 120, 17).WithArguments("a 'Write' other-type", "Data", "TypeNobodyCanWrite", "having no", "Type Permissions: ---------"),
+// /0/Test0.cs(130,9): error RA0002: Tried to perform a 'Write' other-type access to member 'Data' in type 'MemberNobodyCanWrite', despite having no access. Member Permissions: ---------
+VerifyCS.Diagnostic().WithSpan(130, 9, 130, 17).WithArguments("a 'Write' other-type", "Data", "MemberNobodyCanWrite", "having no", "Member Permissions: ---------"),
+// /0/Test0.cs(131,9): error RA0002: Tried to perform a 'Write' other-type access to member 'Data' in type 'MemberNobodyCanWrite', despite having no access. Member Permissions: ---------
+VerifyCS.Diagnostic().WithSpan(131, 9, 131, 17).WithArguments("a 'Write' other-type", "Data", "MemberNobodyCanWrite", "having no", "Member Permissions: ---------")
+            );
+    }
+
+    [Test]
+    public async Task ExecuteTest()
+    {
+        const string code = @"
+using System;
+using Robust.Shared.Analyzers;
+// ReSharper disable RedundantAssignment
+// ReSharper disable UnusedVariable
+// ReSharper disable ArrangeThisQualifier
+// ReSharper disable UnusedMember.Global
+// ReSharper disable UnusedType.Global
+// ReSharper disable NotAccessedField.Global
+// ReSharper disable RedundantDefaultMemberInitializer
+// ReSharper disable ReturnValueOfPureMethodIsNotUsed
+
+public struct MyData
+{
+    public int MyField;
+    public void MyMethod() {}
+}
+
+[Access(typeof(FriendlyClass),
+    Self = AccessPermissions.None,
+    Friend = AccessPermissions.None,
+    Other = AccessPermissions.None)]
+public sealed class TypeNobodyCanExecute
+{
+    public MyData Data = default;
+
+    [Access(typeof(FriendlyClass),
+        Self = AccessPermissions.Execute,
+        Friend = AccessPermissions.Execute,
+        Other = AccessPermissions.Execute)]
+    public MyData Data2 = default;
+
+    public void MyMethod() {}
+
+    [Access(typeof(FriendlyClass),
+        Self = AccessPermissions.Execute,
+        Friend = AccessPermissions.Execute,
+        Other = AccessPermissions.Execute)]
+    public void MyMethod2() {}
+
+    public void TestTypeNobodyCanExecute(TypeNobodyCanExecute obj)
+    {
+        // None of these accesses should be allowed.
+        MyMethod();
+        this.MyMethod();
+        obj.MyMethod();
+
+        Data.MyMethod();
+        this.Data.MyMethod();
+        obj.Data.MyMethod();
+
+        Data.MyField.ToString();
+        this.Data.MyField.ToString();
+        obj.Data.MyField.ToString();
+
+        // All of these accesses should be fine.
+        MyMethod2();
+        this.MyMethod2();
+        obj.MyMethod2();
+
+        Data2.MyMethod();
+        this.Data2.MyMethod();
+        obj.Data2.MyMethod();
+
+        Data2.MyField.ToString();
+        this.Data2.ToString();
+        obj.Data2.ToString();
+    }
+}
+
+[Access(typeof(FriendlyClass),
+    Self = AccessPermissions.Execute,
+    Friend = AccessPermissions.Execute,
+    Other = AccessPermissions.Execute)]
+public sealed class MemberNobodyCanExecute
+{
+    [Access(typeof(FriendlyClass),
+        Self = AccessPermissions.None,
+        Friend = AccessPermissions.None,
+        Other = AccessPermissions.None)]
+    public MyData Data = default;
+
+    public MyData Data2 = default;
+
+    [Access(typeof(FriendlyClass),
+        Self = AccessPermissions.None,
+        Friend = AccessPermissions.None,
+        Other = AccessPermissions.None)]
+    public void MyMethod() {}
+
+    public void MyMethod2() {}
+
+    public void TestMemberNobodyCanExecute(TypeNobodyCanExecute obj)
+    {
+        // None of these accesses should be allowed.
+        MyMethod();
+        this.MyMethod();
+        obj.MyMethod();
+
+        Data.MyMethod();
+        this.Data.MyMethod();
+        obj.Data.MyMethod();
+
+        Data.MyField.ToString();
+        this.Data.MyField.ToString();
+        obj.Data.MyField.ToString();
+
+        // All of these accesses should be fine.
+        MyMethod2();
+        this.MyMethod2();
+        obj.MyMethod2();
+
+        Data2.MyMethod();
+        this.Data2.MyMethod();
+        obj.Data2.MyMethod();
+
+        Data2.MyField.ToString();
+        this.Data2.ToString();
+        obj.Data2.ToString();
+    }
+}
+
+public sealed class FriendlyClass
+{
+    public void TestTypeNobodyCanExecute(TypeNobodyCanExecute obj)
+    {
+        // We shouldn't be able to access any of these, even if we're a friend..
+        obj.MyMethod();
+        obj.Data.MyMethod();
+        obj.Data.MyField.ToString();
+
+        // We should be allowed to access all of these, we're friends!
+        obj.MyMethod2();
+        obj.Data2.MyMethod();
+        obj.Data2.MyField.ToString();
+    }
+
+    public void TestMemberNobodyCanExecute(MemberNobodyCanExecute obj)
+    {
+        // We shouldn't be able to access any of these, even if we're a friend..
+        obj.MyMethod();
+        obj.Data.MyMethod();
+        obj.Data.MyField.ToString();
+
+        // We should be allowed to access all of these, we're friends!
+        obj.MyMethod2();
+        obj.Data2.MyMethod();
+        obj.Data2.MyField.ToString();
+    }
+}
+
+public sealed class OtherClass
+{
+    public void TestTypeNobodyCanExecute(TypeNobodyCanExecute obj)
+    {
+        // We shouldn't be able to access any of these, as 'other types' can't..
+        obj.MyMethod();
+        obj.Data.MyMethod();
+        obj.Data.MyField.ToString();
+
+        // We should be allowed to access all of these, they let others Execute!
+        obj.MyMethod2();
+        obj.Data2.MyMethod();
+        obj.Data2.MyField.ToString();
+    }
+
+    public void TestMemberNobodyCanExecute(MemberNobodyCanExecute obj)
+    {
+        // We shouldn't be able to access any of these, as 'other types' can't..
+        obj.MyMethod();
+        obj.Data.MyMethod();
+        obj.Data.MyField.ToString();
+
+        // We should be allowed to access all of these, they let others Execute!
+        obj.MyMethod2();
+        obj.Data2.MyMethod();
+        obj.Data2.MyField.ToString();
+    }
+}";
+
+        await Verifier(code,
+            // AUTO-GENERATED DIAGNOSTICS BELOW //
+// /0/Test0.cs(44,9): error RA0002: Tried to perform an 'Execute' same-type access to member 'MyMethod' in type 'TypeNobodyCanExecute', despite having no access. Type Permissions: ---------
+VerifyCS.Diagnostic().WithSpan(44, 9, 44, 19).WithArguments("an 'Execute' same-type", "MyMethod", "TypeNobodyCanExecute", "having no", "Type Permissions: ---------"),
+// /0/Test0.cs(45,9): error RA0002: Tried to perform an 'Execute' same-type access to member 'MyMethod' in type 'TypeNobodyCanExecute', despite having no access. Type Permissions: ---------
+VerifyCS.Diagnostic().WithSpan(45, 9, 45, 24).WithArguments("an 'Execute' same-type", "MyMethod", "TypeNobodyCanExecute", "having no", "Type Permissions: ---------"),
+// /0/Test0.cs(46,9): error RA0002: Tried to perform an 'Execute' same-type access to member 'MyMethod' in type 'TypeNobodyCanExecute', despite having no access. Type Permissions: ---------
+VerifyCS.Diagnostic().WithSpan(46, 9, 46, 23).WithArguments("an 'Execute' same-type", "MyMethod", "TypeNobodyCanExecute", "having no", "Type Permissions: ---------"),
+// /0/Test0.cs(48,9): error RA0002: Tried to perform an 'Execute' same-type access to member 'Data' in type 'TypeNobodyCanExecute', despite having no access. Type Permissions: ---------
+VerifyCS.Diagnostic().WithSpan(48, 9, 48, 13).WithArguments("an 'Execute' same-type", "Data", "TypeNobodyCanExecute", "having no", "Type Permissions: ---------"),
+// /0/Test0.cs(49,9): error RA0002: Tried to perform an 'Execute' same-type access to member 'Data' in type 'TypeNobodyCanExecute', despite having no access. Type Permissions: ---------
+VerifyCS.Diagnostic().WithSpan(49, 9, 49, 18).WithArguments("an 'Execute' same-type", "Data", "TypeNobodyCanExecute", "having no", "Type Permissions: ---------"),
+// /0/Test0.cs(50,9): error RA0002: Tried to perform an 'Execute' same-type access to member 'Data' in type 'TypeNobodyCanExecute', despite having no access. Type Permissions: ---------
+VerifyCS.Diagnostic().WithSpan(50, 9, 50, 17).WithArguments("an 'Execute' same-type", "Data", "TypeNobodyCanExecute", "having no", "Type Permissions: ---------"),
+// /0/Test0.cs(52,9): error RA0002: Tried to perform an 'Execute' same-type access to member 'Data' in type 'TypeNobodyCanExecute', despite having no access. Type Permissions: ---------
+VerifyCS.Diagnostic().WithSpan(52, 9, 52, 13).WithArguments("an 'Execute' same-type", "Data", "TypeNobodyCanExecute", "having no", "Type Permissions: ---------"),
+// /0/Test0.cs(53,9): error RA0002: Tried to perform an 'Execute' same-type access to member 'Data' in type 'TypeNobodyCanExecute', despite having no access. Type Permissions: ---------
+VerifyCS.Diagnostic().WithSpan(53, 9, 53, 18).WithArguments("an 'Execute' same-type", "Data", "TypeNobodyCanExecute", "having no", "Type Permissions: ---------"),
+// /0/Test0.cs(54,9): error RA0002: Tried to perform an 'Execute' same-type access to member 'Data' in type 'TypeNobodyCanExecute', despite having no access. Type Permissions: ---------
+VerifyCS.Diagnostic().WithSpan(54, 9, 54, 17).WithArguments("an 'Execute' same-type", "Data", "TypeNobodyCanExecute", "having no", "Type Permissions: ---------"),
+// /0/Test0.cs(96,9): error RA0002: Tried to perform an 'Execute' same-type access to member 'MyMethod' in type 'MemberNobodyCanExecute', despite having no access. Member Permissions: ---------
+VerifyCS.Diagnostic().WithSpan(96, 9, 96, 19).WithArguments("an 'Execute' same-type", "MyMethod", "MemberNobodyCanExecute", "having no", "Member Permissions: ---------"),
+// /0/Test0.cs(97,9): error RA0002: Tried to perform an 'Execute' same-type access to member 'MyMethod' in type 'MemberNobodyCanExecute', despite having no access. Member Permissions: ---------
+VerifyCS.Diagnostic().WithSpan(97, 9, 97, 24).WithArguments("an 'Execute' same-type", "MyMethod", "MemberNobodyCanExecute", "having no", "Member Permissions: ---------"),
+// /0/Test0.cs(98,9): error RA0002: Tried to perform an 'Execute' other-type access to member 'MyMethod' in type 'TypeNobodyCanExecute', despite having no access. Type Permissions: ---------
+VerifyCS.Diagnostic().WithSpan(98, 9, 98, 23).WithArguments("an 'Execute' other-type", "MyMethod", "TypeNobodyCanExecute", "having no", "Type Permissions: ---------"),
+// /0/Test0.cs(100,9): error RA0002: Tried to perform an 'Execute' same-type access to member 'Data' in type 'MemberNobodyCanExecute', despite having no access. Member Permissions: ---------
+VerifyCS.Diagnostic().WithSpan(100, 9, 100, 13).WithArguments("an 'Execute' same-type", "Data", "MemberNobodyCanExecute", "having no", "Member Permissions: ---------"),
+// /0/Test0.cs(101,9): error RA0002: Tried to perform an 'Execute' same-type access to member 'Data' in type 'MemberNobodyCanExecute', despite having no access. Member Permissions: ---------
+VerifyCS.Diagnostic().WithSpan(101, 9, 101, 18).WithArguments("an 'Execute' same-type", "Data", "MemberNobodyCanExecute", "having no", "Member Permissions: ---------"),
+// /0/Test0.cs(102,9): error RA0002: Tried to perform an 'Execute' other-type access to member 'Data' in type 'TypeNobodyCanExecute', despite having no access. Type Permissions: ---------
+VerifyCS.Diagnostic().WithSpan(102, 9, 102, 17).WithArguments("an 'Execute' other-type", "Data", "TypeNobodyCanExecute", "having no", "Type Permissions: ---------"),
+// /0/Test0.cs(104,9): error RA0002: Tried to perform an 'Execute' same-type access to member 'Data' in type 'MemberNobodyCanExecute', despite having no access. Member Permissions: ---------
+VerifyCS.Diagnostic().WithSpan(104, 9, 104, 13).WithArguments("an 'Execute' same-type", "Data", "MemberNobodyCanExecute", "having no", "Member Permissions: ---------"),
+// /0/Test0.cs(105,9): error RA0002: Tried to perform an 'Execute' same-type access to member 'Data' in type 'MemberNobodyCanExecute', despite having no access. Member Permissions: ---------
+VerifyCS.Diagnostic().WithSpan(105, 9, 105, 18).WithArguments("an 'Execute' same-type", "Data", "MemberNobodyCanExecute", "having no", "Member Permissions: ---------"),
+// /0/Test0.cs(106,9): error RA0002: Tried to perform an 'Execute' other-type access to member 'Data' in type 'TypeNobodyCanExecute', despite having no access. Type Permissions: ---------
+VerifyCS.Diagnostic().WithSpan(106, 9, 106, 17).WithArguments("an 'Execute' other-type", "Data", "TypeNobodyCanExecute", "having no", "Type Permissions: ---------"),
+// /0/Test0.cs(128,9): error RA0002: Tried to perform an 'Execute' friend-type access to member 'MyMethod' in type 'TypeNobodyCanExecute', despite having no access. Type Permissions: ---------
+VerifyCS.Diagnostic().WithSpan(128, 9, 128, 23).WithArguments("an 'Execute' friend-type", "MyMethod", "TypeNobodyCanExecute", "having no", "Type Permissions: ---------"),
+// /0/Test0.cs(129,9): error RA0002: Tried to perform an 'Execute' friend-type access to member 'Data' in type 'TypeNobodyCanExecute', despite having no access. Type Permissions: ---------
+VerifyCS.Diagnostic().WithSpan(129, 9, 129, 17).WithArguments("an 'Execute' friend-type", "Data", "TypeNobodyCanExecute", "having no", "Type Permissions: ---------"),
+// /0/Test0.cs(130,9): error RA0002: Tried to perform an 'Execute' friend-type access to member 'Data' in type 'TypeNobodyCanExecute', despite having no access. Type Permissions: ---------
+VerifyCS.Diagnostic().WithSpan(130, 9, 130, 17).WithArguments("an 'Execute' friend-type", "Data", "TypeNobodyCanExecute", "having no", "Type Permissions: ---------"),
+// /0/Test0.cs(141,9): error RA0002: Tried to perform an 'Execute' friend-type access to member 'MyMethod' in type 'MemberNobodyCanExecute', despite having no access. Member Permissions: ---------
+VerifyCS.Diagnostic().WithSpan(141, 9, 141, 23).WithArguments("an 'Execute' friend-type", "MyMethod", "MemberNobodyCanExecute", "having no", "Member Permissions: ---------"),
+// /0/Test0.cs(142,9): error RA0002: Tried to perform an 'Execute' friend-type access to member 'Data' in type 'MemberNobodyCanExecute', despite having no access. Member Permissions: ---------
+VerifyCS.Diagnostic().WithSpan(142, 9, 142, 17).WithArguments("an 'Execute' friend-type", "Data", "MemberNobodyCanExecute", "having no", "Member Permissions: ---------"),
+// /0/Test0.cs(143,9): error RA0002: Tried to perform an 'Execute' friend-type access to member 'Data' in type 'MemberNobodyCanExecute', despite having no access. Member Permissions: ---------
+VerifyCS.Diagnostic().WithSpan(143, 9, 143, 17).WithArguments("an 'Execute' friend-type", "Data", "MemberNobodyCanExecute", "having no", "Member Permissions: ---------"),
+// /0/Test0.cs(157,9): error RA0002: Tried to perform an 'Execute' other-type access to member 'MyMethod' in type 'TypeNobodyCanExecute', despite having no access. Type Permissions: ---------
+VerifyCS.Diagnostic().WithSpan(157, 9, 157, 23).WithArguments("an 'Execute' other-type", "MyMethod", "TypeNobodyCanExecute", "having no", "Type Permissions: ---------"),
+// /0/Test0.cs(158,9): error RA0002: Tried to perform an 'Execute' other-type access to member 'Data' in type 'TypeNobodyCanExecute', despite having no access. Type Permissions: ---------
+VerifyCS.Diagnostic().WithSpan(158, 9, 158, 17).WithArguments("an 'Execute' other-type", "Data", "TypeNobodyCanExecute", "having no", "Type Permissions: ---------"),
+// /0/Test0.cs(159,9): error RA0002: Tried to perform an 'Execute' other-type access to member 'Data' in type 'TypeNobodyCanExecute', despite having no access. Type Permissions: ---------
+VerifyCS.Diagnostic().WithSpan(159, 9, 159, 17).WithArguments("an 'Execute' other-type", "Data", "TypeNobodyCanExecute", "having no", "Type Permissions: ---------"),
+// /0/Test0.cs(170,9): error RA0002: Tried to perform an 'Execute' other-type access to member 'MyMethod' in type 'MemberNobodyCanExecute', despite having no access. Member Permissions: ---------
+VerifyCS.Diagnostic().WithSpan(170, 9, 170, 23).WithArguments("an 'Execute' other-type", "MyMethod", "MemberNobodyCanExecute", "having no", "Member Permissions: ---------"),
+// /0/Test0.cs(171,9): error RA0002: Tried to perform an 'Execute' other-type access to member 'Data' in type 'MemberNobodyCanExecute', despite having no access. Member Permissions: ---------
+VerifyCS.Diagnostic().WithSpan(171, 9, 171, 17).WithArguments("an 'Execute' other-type", "Data", "MemberNobodyCanExecute", "having no", "Member Permissions: ---------"),
+// /0/Test0.cs(172,9): error RA0002: Tried to perform an 'Execute' other-type access to member 'Data' in type 'MemberNobodyCanExecute', despite having no access. Member Permissions: ---------
+VerifyCS.Diagnostic().WithSpan(172, 9, 172, 17).WithArguments("an 'Execute' other-type", "Data", "MemberNobodyCanExecute", "having no", "Member Permissions: ---------")
+            );
+    }
+}

Robust.Analyzers.Tests/Robust.Analyzers.Tests.csproj

@@ -0,0 +1,24 @@
+<Project Sdk="Microsoft.NET.Sdk">
+  <Import Project="..\MSBuild\Robust.Properties.targets" />
+  <Import Project="..\MSBuild\Robust.Engine.props" />
+  
+  <PropertyGroup>
+    <IsPackable>false</IsPackable>
+  </PropertyGroup>
+  
+  <ItemGroup>
+    <PackageReference Include="Microsoft.CodeAnalysis.Analyzer.Testing" Version="1.1.1"/>
+    <PackageReference Include="Microsoft.CodeAnalysis.CSharp" Version="4.0.1"/>
+    <PackageReference Include="Microsoft.CodeAnalysis.CSharp.Analyzer.Testing.NUnit" Version="1.1.1"/>
+    <PackageReference Include="Microsoft.CodeAnalysis.CSharp.Workspaces" Version="4.0.1"/>
+    <PackageReference Include="NUnit" Version="3.13.2"/>
+    <PackageReference Include="NUnit.ConsoleRunner" Version="3.15.0"/>
+    <PackageReference Include="NUnit3TestAdapter" Version="4.2.1"/>
+    <PackageReference Include="NUnit.Analyzers" Version="3.3.0"/>
+    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.2.0" />
+  </ItemGroup>
+  
+  <ItemGroup>
+    <ProjectReference Include="..\Robust.Analyzers\Robust.Analyzers.csproj"/>
+  </ItemGroup>
+</Project>

Robust.Analyzers/AccessAnalyzer.cs

@@ -0,0 +1,253 @@
+using System.Collections.Generic;
+using System.Collections.Immutable;
+using System.Diagnostics.CodeAnalysis;
+using Microsoft.CodeAnalysis;
+using Microsoft.CodeAnalysis.Diagnostics;
+using Microsoft.CodeAnalysis.Operations;
+using Robust.Shared.Analyzers.Implementation;
+
+namespace Robust.Analyzers
+{
+    [DiagnosticAnalyzer(LanguageNames.CSharp)]
+    public class AccessAnalyzer : DiagnosticAnalyzer
+    {
+        private const string AccessAttributeType = "Robust.Shared.Analyzers.AccessAttribute";
+        private const string PureAttributeType = "System.Diagnostics.Contracts.PureAttribute";
+
+        [SuppressMessage("ReSharper", "RS2008")]
+        private static readonly DiagnosticDescriptor AccessRule = new (
+            Diagnostics.IdAccess,
+            "Invalid access",
+            "Tried to perform {0} access to member '{1}' in type '{2}', despite {3} access. {4}.",
+            "Usage",
+            DiagnosticSeverity.Error,
+            true,
+            "Make sure to give the accessing type the correct access permissions.");
+
+        public override ImmutableArray<DiagnosticDescriptor> SupportedDiagnostics =>
+            ImmutableArray.Create(AccessRule);
+
+        public override void Initialize(AnalysisContext context)
+        {
+            context.ConfigureGeneratedCodeAnalysis(GeneratedCodeAnalysisFlags.Analyze | GeneratedCodeAnalysisFlags.ReportDiagnostics);
+            context.EnableConcurrentExecution();
+            context.RegisterOperationAction(CheckFriendship,
+                OperationKind.FieldReference,
+                OperationKind.PropertyReference,
+                OperationKind.MethodReference,
+                OperationKind.Invocation);
+        }
+
+        private void CheckFriendship(OperationAnalysisContext context)
+        {
+            var operation = context.Operation;
+
+            // The symbol representing the member being accessed.
+            ISymbol member;
+
+            // The operation to target when determining access type.
+            IOperation targetAccess;
+
+            switch (operation)
+            {
+                case IMemberReferenceOperation memberRef:
+                {
+                    member = memberRef.Member;
+                    targetAccess = memberRef.Parent;
+                    break;
+                }
+
+                case IInvocationOperation invocation:
+                {
+                    member = invocation.TargetMethod;
+                    targetAccess = invocation;
+                    break;
+                }
+
+                default:
+                    return;
+            }
+
+            // Get the info of the type defining the member, so we can check the attributes later...
+            var accessedType = member.ContainingType;
+
+            // Get the attributes
+            var friendAttribute = context.Compilation.GetTypeByMetadataName(AccessAttributeType);
+
+            // Get the type that is containing this expression, or, the type where this is happening.
+            if (context.ContainingSymbol?.ContainingType is not {} accessingType)
+                return;
+
+            // Determine which type of access is happening here... Read, write or execute?
+            var accessAttempt = DetermineAccess(context, targetAccess, operation);
+
+            // Check whether this is a "self" access, including inheritors.
+            var selfAccess = InheritsFromOrEquals(accessingType, accessedType);
+
+            // Helper function to deduplicate attribute-checking code.
+            bool CheckAttributeFriendship(AttributeData attribute, bool isMemberAttribute)
+            {
+                // If the attribute isn't the friend attribute, we don't care about it.
+                if (!SymbolEqualityComparer.Default.Equals(attribute.AttributeClass, friendAttribute))
+                    return false;
+
+                var self    = AccessAttribute.SelfDefaultPermissions;
+                var friends = AccessAttribute.FriendDefaultPermissions;
+                var others  = AccessAttribute.OtherDefaultPermissions;
+
+                foreach (var kv in attribute.NamedArguments)
+                {
+                    if (kv.Value.Value is not byte value)
+                        continue;
+
+                    var permissions = (AccessPermissions) value;
+
+                    switch (kv.Key)
+                    {
+                        case nameof(AccessAttribute.Self):
+                        {
+                            self = permissions;
+                            break;
+                        }
+
+                        case nameof(AccessAttribute.Friend):
+                        {
+                            friends = permissions;
+                            break;
+                        }
+
+                        case nameof(AccessAttribute.Other):
+                        {
+                            others = permissions;
+                            break;
+                        }
+
+                        default:
+                            continue;
+                    }
+                }
+
+                // By default, we will check the "other" permissions unless we find we're dealing with a friend or self.
+                var permissionCheck = others;
+
+                // Human-readable relation between accessing and accessed types.
+                var accessingRelation = "other-type";
+
+                if (!selfAccess)
+                {
+                    // This is not a self-access, so we need to determine whether the accessing type is a friend.
+                    // Check all types allowed in the friend attribute. (We assume there's only one constructor arg.)
+                    var types = attribute.ConstructorArguments[0].Values;
+
+                    foreach (var constant in types)
+                    {
+                        // Check if the value is a type...
+                        if (constant.Value is not INamedTypeSymbol friendType)
+                            continue;
+
+                        // Check if the accessing type is specified in the attribute...
+                        if (!InheritsFromOrEquals(accessingType, friendType))
+                            continue;
+
+                        // Set the permissions check to the friend permissions!
+                        permissionCheck = friends;
+                        accessingRelation = "friend-type";
+                        break;
+                    }
+                }
+                else
+                {
+                    // Self-access, so simply set the permissions check to self.
+                    permissionCheck = self;
+                    accessingRelation = "same-type";
+                }
+
+                // If we allow this access, return! All is good.
+                if ((accessAttempt & permissionCheck) != 0)
+                    return true;
+
+                // Access denied! Report an error.
+                context.ReportDiagnostic(
+                    Diagnostic.Create(AccessRule, operation.Syntax.GetLocation(),
+                        $"a{(accessAttempt == AccessPermissions.Execute ? "n" : "")} '{accessAttempt}' {accessingRelation}",
+                        $"{member.Name}",
+                        $"{accessedType.Name}",
+                        $"{(permissionCheck == AccessPermissions.None ? "having no" : $"only having '{permissionCheck}'")}",
+                        $"{(isMemberAttribute ? "Member" : "Type")} Permissions: {self.ToUnixPermissions()}{friends.ToUnixPermissions()}{others.ToUnixPermissions()}"));
+
+                // Only return ONE error.
+                return true;
+            }
+
+            // Check attributes in the member first, since they take priority and can override type restrictions.
+            foreach (var attribute in member.GetAttributes())
+            {
+                if(CheckAttributeFriendship(attribute, true))
+                    return;
+            }
+
+            // Check attributes in the type containing the member last.
+            foreach (var attribute in accessedType.GetAttributes())
+            {
+                if(CheckAttributeFriendship(attribute, false))
+                    return;
+            }
+        }
+
+        private static AccessPermissions DetermineAccess(OperationAnalysisContext context, IOperation operation, IOperation original)
+        {
+            switch (operation)
+            {
+                case IAssignmentOperation assign:
+                {
+                    return assign.Target.Equals(original) ? AccessPermissions.Write : AccessPermissions.Read;
+                }
+
+                case IInvocationOperation invoke:
+                {
+                    var pureAttribute = context.Compilation.GetTypeByMetadataName(PureAttributeType);
+
+                    foreach (var attribute in invoke.TargetMethod.GetAttributes())
+                    {
+                        // Pure methods are treated as read accesses.
+                        if (SymbolEqualityComparer.Default.Equals(attribute.AttributeClass, pureAttribute))
+                            return AccessPermissions.Read;
+                    }
+
+                    return AccessPermissions.Execute;
+                }
+
+                case IMemberReferenceOperation member:
+                {
+                    return DetermineAccess(context, member.Parent, operation);
+                }
+
+                default:
+                {
+                    return AccessPermissions.Read;
+                }
+            }
+        }
+
+        private bool InheritsFromOrEquals(INamedTypeSymbol type, INamedTypeSymbol baseType)
+        {
+            foreach (var otherType in GetBaseTypesAndThis(type))
+            {
+                if (SymbolEqualityComparer.Default.Equals(otherType, baseType))
+                    return true;
+            }
+
+            return false;
+        }
+
+        private IEnumerable<INamedTypeSymbol> GetBaseTypesAndThis(INamedTypeSymbol namedType)
+        {
+            var current = namedType;
+            while (current != null)
+            {
+                yield return current;
+                current = current.BaseType;
+            }
+        }
+    }
+}

Robust.Analyzers/Diagnostics.cs

@@ -1,10 +1,15 @@
 using Microsoft.CodeAnalysis;
 
-namespace Robust.Generators
+namespace Robust.Analyzers;
+
+public static class Diagnostics
 {
-    public static class Diagnostics
-    {
-        public static SuppressionDescriptor MeansImplicitAssignment =>
-            new SuppressionDescriptor("RADC1000", "CS0649", "Marked as implicitly assigned.");
-    }
+    public const string IdExplicitInterface = "RA0000";
+    public const string IdSerializable = "RA0001";
+    public const string IdAccess = "RA0002";
+    public const string IdExplicitVirtual = "RA0003";
+    public const string IdTaskResult = "RA0004";
+
+    public static SuppressionDescriptor MeansImplicitAssignment =>
+        new SuppressionDescriptor("RADC1000", "CS0649", "Marked as implicitly assigned.");
 }

Robust.Analyzers/ExplicitInterfaceAnalyzer.cs

@@ -24,14 +24,14 @@ namespace Robust.Analyzers
             SyntaxKind.OverrideKeyword
         };
 
-        public const string DiagnosticId = "RA0000";
-
-        private const string Title = "No explicit interface specified";
-        private const string MessageFormat = "No explicit interface specified";
-        private const string Description = "Make sure to specify the interface in your method-declaration.";
-        private const string Category = "Usage";
-
-        [SuppressMessage("ReSharper", "RS2008")] private static readonly DiagnosticDescriptor Rule = new DiagnosticDescriptor(DiagnosticId, Title, MessageFormat, Category, DiagnosticSeverity.Warning, isEnabledByDefault: true, description: Description);
+        [SuppressMessage("ReSharper", "RS2008")] private static readonly DiagnosticDescriptor Rule = new(
+            Diagnostics.IdExplicitInterface,
+            "No explicit interface specified",
+            "No explicit interface specified",
+            "Usage",
+            DiagnosticSeverity.Warning,
+            isEnabledByDefault: true,
+            description: "Make sure to specify the interface in your method-declaration.");
 
         private const string RequiresExplicitImplementationAttributeMetadataName =
             "Robust.Shared.Analyzers.RequiresExplicitImplementationAttribute";

Robust.Analyzers/ExplicitVirtualAnalyzer.cs

@@ -0,0 +1,176 @@
+using System.Collections.Immutable;
+using System.Diagnostics.CodeAnalysis;
+using System.Linq;
+using Microsoft.CodeAnalysis;
+using Microsoft.CodeAnalysis.CSharp;
+using Microsoft.CodeAnalysis.CSharp.Syntax;
+using Microsoft.CodeAnalysis.Diagnostics;
+
+namespace Robust.Analyzers;
+
+[DiagnosticAnalyzer(LanguageNames.CSharp)]
+public sealed class ExplicitVirtualAnalyzer : DiagnosticAnalyzer
+{
+    internal const string Attribute = "Robust.Shared.Analyzers.VirtualAttribute";
+
+    [SuppressMessage("ReSharper", "RS2008")]
+    private static readonly DiagnosticDescriptor Rule = new(
+        Diagnostics.IdExplicitVirtual,
+        "Class must be explicitly marked as [Virtual], abstract, static or sealed",
+        "Class must be explicitly marked as [Virtual], abstract, static or sealed",
+        "Usage",
+        DiagnosticSeverity.Warning,
+        isEnabledByDefault: true,
+        description: "Class must be explicitly marked as [Virtual], abstract, static or sealed.");
+
+    public override ImmutableArray<DiagnosticDescriptor> SupportedDiagnostics => ImmutableArray.Create(Rule);
+
+    public override void Initialize(AnalysisContext context)
+    {
+        context.ConfigureGeneratedCodeAnalysis(GeneratedCodeAnalysisFlags.None);
+        context.EnableConcurrentExecution();
+        context.RegisterSyntaxNodeAction(AnalyzeNode, SyntaxKind.ClassDeclaration);
+    }
+
+    private static bool HasAttribute(INamedTypeSymbol namedTypeSymbol, INamedTypeSymbol attrSymbol)
+    {
+        return namedTypeSymbol.GetAttributes()
+            .Any(a => SymbolEqualityComparer.Default.Equals(a.AttributeClass, attrSymbol));
+    }
+
+    private static void AnalyzeNode(SyntaxNodeAnalysisContext context)
+    {
+        var attrSymbol = context.Compilation.GetTypeByMetadataName(Attribute);
+        var classDecl = (ClassDeclarationSyntax)context.Node;
+        var classSymbol = context.SemanticModel.GetDeclaredSymbol(classDecl);
+        if (classSymbol == null)
+            return;
+
+        if (classSymbol.IsSealed || classSymbol.IsAbstract || classSymbol.IsStatic)
+            return;
+
+        if (HasAttribute(classSymbol, attrSymbol))
+            return;
+
+        var diag = Diagnostic.Create(Rule, classDecl.Keyword.GetLocation());
+        context.ReportDiagnostic(diag);
+    }
+}
+
+// Doesn't work as I'd hoped: Roslyn doesn't provide an API for global usings and I can't get batch changes to work.
+/*
+[ExportCodeFixProvider(LanguageNames.CSharp)]
+public sealed class ExplicitVirtualCodeFixProvider : CodeFixProvider
+{
+    private const string TitleSealed = "Annotate class as sealed.";
+    private const string TitleVirtual = "Annotate class as [Virtual].";
+    private const string TitleAbstract = "Annotate class as abstract.";
+    private const string TitleStatic = "Annotate class as static.";
+
+    public override async Task RegisterCodeFixesAsync(CodeFixContext context)
+    {
+        var root = await context.Document.GetSyntaxRootAsync(context.CancellationToken);
+
+        foreach (var diagnostic in context.Diagnostics)
+        {
+            var span = diagnostic.Location.SourceSpan;
+            var classDecl = root.FindToken(span.Start).Parent.AncestorsAndSelf().OfType<ClassDeclarationSyntax>()
+                .First();
+
+            context.RegisterCodeFix(
+                CodeAction.Create(
+                    TitleVirtual,
+                    c => FixVirtualAsync(context.Document, classDecl, c),
+                    TitleVirtual),
+                diagnostic);
+
+            context.RegisterCodeFix(
+                CodeAction.Create(
+                    TitleStatic,
+                    c => FixStaticAsync(context.Document, classDecl, c),
+                    TitleStatic),
+                diagnostic);
+
+            context.RegisterCodeFix(
+                CodeAction.Create(
+                    TitleSealed,
+                    c => FixSealedAsync(context.Document, classDecl, c),
+                    TitleSealed),
+                diagnostic);
+
+            context.RegisterCodeFix(
+                CodeAction.Create(
+                    TitleAbstract,
+                    c => FixAbstractAsync(context.Document, classDecl, c),
+                    TitleAbstract),
+                diagnostic);
+        }
+    }
+
+    private async Task<Document> FixVirtualAsync(
+        Document document,
+        ClassDeclarationSyntax classDecl,
+        CancellationToken cancellationToken)
+    {
+        var ns = "Robust.Shared.Analyzers";
+        var attrib = SyntaxFactory.Attribute(SyntaxFactory.ParseName("Virtual"));
+
+        var newClassDecl = classDecl.AddAttributeLists(
+            SyntaxFactory.AttributeList(SyntaxFactory.SeparatedList(new[] { attrib })));
+
+        var root = (CompilationUnitSyntax)await document.GetSyntaxRootAsync(cancellationToken);
+        root = root.ReplaceNode(classDecl, newClassDecl);
+
+        var options = await document.GetOptionsAsync(cancellationToken);
+
+        if (root.Usings.All(u => u.Name.ToString() != ns))
+        {
+            root = root.AddUsings(SyntaxFactory.UsingDirective(SyntaxFactory.ParseName(ns)));
+        }
+
+        return document.WithSyntaxRoot(root);
+    }
+
+    private async Task<Document> FixStaticAsync(
+        Document document,
+        ClassDeclarationSyntax classDecl,
+        CancellationToken cancellationToken)
+    {
+        var newClassDecl = classDecl.AddModifiers(SyntaxFactory.Token(SyntaxKind.StaticKeyword));
+
+        var root = (CompilationUnitSyntax)await document.GetSyntaxRootAsync(cancellationToken);
+        root = root.ReplaceNode(classDecl, newClassDecl);
+
+        return document.WithSyntaxRoot(root);
+    }
+
+    private async Task<Document> FixAbstractAsync(
+        Document document,
+        ClassDeclarationSyntax classDecl,
+        CancellationToken cancellationToken)
+    {
+        var newClassDecl = classDecl.AddModifiers(SyntaxFactory.Token(SyntaxKind.AbstractKeyword));
+
+        var root = (CompilationUnitSyntax)await document.GetSyntaxRootAsync(cancellationToken);
+        root = root.ReplaceNode(classDecl, newClassDecl);
+
+        return document.WithSyntaxRoot(root);
+    }
+
+    private async Task<Document> FixSealedAsync(
+        Document document,
+        ClassDeclarationSyntax classDecl,
+        CancellationToken cancellationToken)
+    {
+        var newClassDecl = classDecl.AddModifiers(SyntaxFactory.Token(SyntaxKind.SealedKeyword));
+
+        var root = (CompilationUnitSyntax)await document.GetSyntaxRootAsync(cancellationToken);
+        root = root.ReplaceNode(classDecl, newClassDecl);
+
+        return document.WithSyntaxRoot(root);
+    }
+
+    public override FixAllProvider GetFixAllProvider() => WellKnownFixAllProviders.BatchFixer;
+    public override ImmutableArray<string> FixableDiagnosticIds => ImmutableArray.Create(Diagnostics.IdExplicitVirtual);
+}
+*/

Robust.Analyzers/FriendAnalyzer.cs

@@ -1,129 +0,0 @@
-using System.Collections.Generic;
-using System.Collections.Immutable;
-using System.Diagnostics.CodeAnalysis;
-using System.Linq;
-using Microsoft.CodeAnalysis;
-using Microsoft.CodeAnalysis.CSharp;
-using Microsoft.CodeAnalysis.CSharp.Syntax;
-using Microsoft.CodeAnalysis.Diagnostics;
-
-namespace Robust.Analyzers
-{
-    [DiagnosticAnalyzer(LanguageNames.CSharp)]
-    public class FriendAnalyzer : DiagnosticAnalyzer
-    {
-        const string FriendAttribute = "Robust.Shared.Analyzers.FriendAttribute";
-
-        public const string DiagnosticId = "RA0002";
-
-        private const string Title = "Tried to access friend-only member";
-        private const string MessageFormat = "Tried to access member \"{0}\" in class \"{1}\" which can only be accessed by friend classes";
-        private const string Description = "Make sure to specify the accessing class in the friends attribute.";
-        private const string Category = "Usage";
-
-        [SuppressMessage("ReSharper", "RS2008")]
-        private static readonly DiagnosticDescriptor Rule = new (DiagnosticId, Title, MessageFormat, Category, DiagnosticSeverity.Error, true, Description);
-
-        public override ImmutableArray<DiagnosticDescriptor> SupportedDiagnostics => ImmutableArray.Create(Rule);
-
-        public override void Initialize(AnalysisContext context)
-        {
-            context.ConfigureGeneratedCodeAnalysis(GeneratedCodeAnalysisFlags.Analyze | GeneratedCodeAnalysisFlags.ReportDiagnostics);
-            context.EnableConcurrentExecution();
-            context.RegisterSyntaxNodeAction(CheckFriendship, SyntaxKind.SimpleMemberAccessExpression);
-        }
-
-        private void CheckFriendship(SyntaxNodeAnalysisContext context)
-        {
-            if (context.Node is not MemberAccessExpressionSyntax memberAccess)
-                return;
-
-            // We only do something if our parent is one of a few types.
-            switch (context.Node.Parent)
-            {
-                // If we're being assigned...
-                case AssignmentExpressionSyntax assignParent:
-                {
-                    if (assignParent.Left != memberAccess)
-                        return;
-                    break;
-                }
-
-                // If we're being invoked...
-                case InvocationExpressionSyntax:
-                    break;
-
-                // Otherwise, do nothing.
-                default:
-                    return;
-            }
-
-            // Get the friend attribute
-            var friendAttr = context.Compilation.GetTypeByMetadataName(FriendAttribute);
-
-            // Get the type that is containing this expression, or, the class where this is happening.
-            if (context.ContainingSymbol?.ContainingType is not { } containingType)
-                return;
-
-            // We check all of our children and get only the identifiers.
-            foreach (var identifier in memberAccess.ChildNodes().Select(node => node as IdentifierNameSyntax))
-            {
-                if (identifier == null) continue;
-
-                // Get the type info of the identifier, so we can check the attributes...
-                if (context.SemanticModel.GetTypeInfo(identifier).ConvertedType is not { } type)
-                    continue;
-
-                // Same-type access is always fine.
-                if (SymbolEqualityComparer.Default.Equals(type, containingType))
-                    continue;
-
-                // Finally, get all attributes of the type, to check if we have any friend classes.
-                foreach (var attribute in type.GetAttributes())
-                {
-                    // If the attribute isn't the friend attribute, continue.
-                    if (!SymbolEqualityComparer.Default.Equals(attribute.AttributeClass, friendAttr))
-                        continue;
-
-                    // Check all types allowed in the friend attribute. (We assume there's only one constructor arg.)
-                    foreach (var constant in attribute.ConstructorArguments[0].Values)
-                    {
-                        // Check if the value is a type...
-                        if (constant.Value is not INamedTypeSymbol t)
-                            continue;
-
-                        // If we find that the containing class is specified in the attribute, return! All is good.
-                        if (InheritsFromOrEquals(containingType, t))
-                            return;
-                    }
-
-                    // Not in a friend class! Report an error.
-                    context.ReportDiagnostic(
-                        Diagnostic.Create(Rule, context.Node.GetLocation(),
-                            $"{context.Node.ToString().Split('.').LastOrDefault()}", $"{type.Name}"));
-                }
-            }
-        }
-
-        private bool InheritsFromOrEquals(INamedTypeSymbol type, INamedTypeSymbol baseType)
-        {
-            foreach (var otherType in GetBaseTypesAndThis(type))
-            {
-                if (SymbolEqualityComparer.Default.Equals(otherType, baseType))
-                    return true;
-            }
-
-            return false;
-        }
-
-        private IEnumerable<INamedTypeSymbol> GetBaseTypesAndThis(INamedTypeSymbol namedType)
-        {
-            var current = namedType;
-            while (current != null)
-            {
-                yield return current;
-                current = current.BaseType;
-            }
-        }
-    }
-}

Robust.Analyzers/MeansImplicitAssigmentSuppressor.cs

@@ -1,9 +1,7 @@
-using System;
 using System.Collections.Immutable;
 using System.Linq;
 using Microsoft.CodeAnalysis;
 using Microsoft.CodeAnalysis.Diagnostics;
-using Robust.Generators;
 
 namespace Robust.Analyzers
 {

Robust.Analyzers/Robust.Analyzers.csproj

@@ -2,13 +2,19 @@
 
   <PropertyGroup>
     <TargetFramework>netstandard2.0</TargetFramework>
-    <LangVersion>9</LangVersion>
+    <LangVersion>10</LangVersion>
   </PropertyGroup>
 
   <ItemGroup>
-    <PackageReference Include="Microsoft.CodeAnalysis.CSharp" Version="3.8.0" PrivateAssets="all" />
-    <PackageReference Include="Microsoft.CodeAnalysis.Analyzers" Version="3.3.2" PrivateAssets="all" />
-    <PackageReference Include="Microsoft.CodeAnalysis.Workspaces.Common" Version="3.8.0" />
+    <PackageReference Include="Microsoft.CodeAnalysis.CSharp" Version="4.0.1" PrivateAssets="all" />
+    <PackageReference Include="Microsoft.CodeAnalysis.Analyzers" Version="3.3.3" PrivateAssets="all" />
+    <PackageReference Include="Microsoft.CodeAnalysis.Workspaces.Common" Version="4.0.1" />
+  </ItemGroup>
+
+  <ItemGroup>
+    <!-- Needed for FriendAnalyzer. -->
+    <Compile Include="..\Robust.Shared\Analyzers\AccessAttribute.cs" />
+    <Compile Include="..\Robust.Shared\Analyzers\AccessPermissions.cs" />
   </ItemGroup>
 
 </Project>

Robust.Analyzers/SerializableAnalyzer.cs

@@ -17,19 +17,21 @@ namespace Robust.Analyzers
     public class SerializableAnalyzer : DiagnosticAnalyzer
     {
         // Metadata of the analyzer
-        public const string DiagnosticId = "RA0001";
 
         // You could use LocalizedString but it's a little more complicated for this sample
-        private const string Title = "Class not marked as (Net)Serializable";
-        private const string MessageFormat = "Class not marked as (Net)Serializable";
-        private const string Description = "The class should be marked as (Net)Serializable.";
-        private const string Category = "Usage";
 
         private const string RequiresSerializableAttributeMetadataName = "Robust.Shared.Analyzers.RequiresSerializableAttribute";
         private const string SerializableAttributeMetadataName = "System.SerializableAttribute";
         private const string NetSerializableAttributeMetadataName = "Robust.Shared.Serialization.NetSerializableAttribute";
 
-        [SuppressMessage("ReSharper", "RS2008")] private static readonly DiagnosticDescriptor Rule = new DiagnosticDescriptor(DiagnosticId, Title, MessageFormat, Category, DiagnosticSeverity.Warning, isEnabledByDefault: true, description: Description);
+        [SuppressMessage("ReSharper", "RS2008")] private static readonly DiagnosticDescriptor Rule = new(
+            Diagnostics.IdSerializable,
+            "Class not marked as (Net)Serializable",
+            "Class not marked as (Net)Serializable",
+            "Usage",
+            DiagnosticSeverity.Warning,
+            isEnabledByDefault: true,
+            description: "The class should be marked as (Net)Serializable.");
 
         public override ImmutableArray<DiagnosticDescriptor> SupportedDiagnostics => ImmutableArray.Create(Rule);
 
@@ -139,7 +141,8 @@ namespace Robust.Analyzers
             return document.WithSyntaxRoot(root);
         }
 
-        public sealed override ImmutableArray<string> FixableDiagnosticIds => ImmutableArray.Create(SerializableAnalyzer.DiagnosticId);
+        public sealed override ImmutableArray<string> FixableDiagnosticIds
+            => ImmutableArray.Create(Diagnostics.IdSerializable);
 
         public override FixAllProvider GetFixAllProvider()
         {

Robust.Analyzers/TaskResultAnalyzer.cs

@@ -0,0 +1,44 @@
+using System.Collections.Immutable;
+using System.Diagnostics.CodeAnalysis;
+using Microsoft.CodeAnalysis;
+using Microsoft.CodeAnalysis.Diagnostics;
+using Microsoft.CodeAnalysis.Operations;
+
+namespace Robust.Analyzers;
+
+[DiagnosticAnalyzer(LanguageNames.CSharp)]
+public sealed class TaskResultAnalyzer : DiagnosticAnalyzer
+{
+    [SuppressMessage("ReSharper", "RS2008")]
+    private static readonly DiagnosticDescriptor ResultRule = new DiagnosticDescriptor(
+        Diagnostics.IdTaskResult,
+        "Risk of deadlock from accessing Task<T>.Result",
+        "Accessing Task<T>.Result is dangerous and can cause deadlocks in some contexts. If you understand how this works and are certain that you aren't causing a deadlock here, mute this error with #pragma.",
+        "Usage",
+        DiagnosticSeverity.Error,
+        true);
+
+    public override ImmutableArray<DiagnosticDescriptor> SupportedDiagnostics =>
+        ImmutableArray.Create(ResultRule);
+
+    public override void Initialize(AnalysisContext context)
+    {
+        context.ConfigureGeneratedCodeAnalysis(GeneratedCodeAnalysisFlags.None);
+        context.EnableConcurrentExecution();
+        context.RegisterOperationAction(Check, OperationKind.PropertyReference);
+    }
+
+    private static void Check(OperationAnalysisContext context)
+    {
+        var taskType = context.Compilation.GetTypeByMetadataName("System.Threading.Tasks.Task`1");
+
+        var operation = (IPropertyReferenceOperation) context.Operation;
+        var member = operation.Member;
+
+        if (member.Name == "Result" && taskType.Equals(member.ContainingType.ConstructedFrom, SymbolEqualityComparer.Default))
+        {
+            var diag = Diagnostic.Create(ResultRule, operation.Syntax.GetLocation());
+            context.ReportDiagnostic(diag);
+        }
+    }
+}

Robust.Benchmarks/Configs/DefaultSQLConfig.cs

@@ -0,0 +1,53 @@
+using System.Collections.Generic;
+using System.Globalization;
+using BenchmarkDotNet.Analysers;
+using BenchmarkDotNet.Columns;
+using BenchmarkDotNet.Configs;
+using BenchmarkDotNet.Diagnosers;
+using BenchmarkDotNet.Exporters;
+using BenchmarkDotNet.Filters;
+using BenchmarkDotNet.Jobs;
+using BenchmarkDotNet.Loggers;
+using BenchmarkDotNet.Order;
+using BenchmarkDotNet.Reports;
+using BenchmarkDotNet.Validators;
+using Robust.Benchmarks.Exporters;
+
+namespace Robust.Benchmarks.Configs;
+
+public sealed class DefaultSQLConfig : IConfig
+{
+    public static readonly IConfig Instance = new DefaultSQLConfig();
+
+    private DefaultSQLConfig(){}
+
+    public IEnumerable<IExporter> GetExporters()
+    {
+        yield return SQLExporter.Default;
+    }
+
+    public IEnumerable<IColumnProvider> GetColumnProviders() => DefaultConfig.Instance.GetColumnProviders();
+
+    public IEnumerable<ILogger> GetLoggers() => DefaultConfig.Instance.GetLoggers();
+
+    public IEnumerable<IDiagnoser> GetDiagnosers() => DefaultConfig.Instance.GetDiagnosers();
+
+    public IEnumerable<IAnalyser> GetAnalysers() => DefaultConfig.Instance.GetAnalysers();
+
+    public IEnumerable<Job> GetJobs() => DefaultConfig.Instance.GetJobs();
+
+    public IEnumerable<IValidator> GetValidators() => DefaultConfig.Instance.GetValidators();
+
+    public IEnumerable<HardwareCounter> GetHardwareCounters() => DefaultConfig.Instance.GetHardwareCounters();
+
+    public IEnumerable<IFilter> GetFilters() => DefaultConfig.Instance.GetFilters();
+
+    public IEnumerable<BenchmarkLogicalGroupRule> GetLogicalGroupRules() => DefaultConfig.Instance.GetLogicalGroupRules();
+
+    public IOrderer Orderer => DefaultConfig.Instance.Orderer!;
+    public SummaryStyle SummaryStyle => DefaultConfig.Instance.SummaryStyle;
+    public ConfigUnionRule UnionRule => DefaultConfig.Instance.UnionRule;
+    public string ArtifactsPath => DefaultConfig.Instance.ArtifactsPath;
+    public CultureInfo CultureInfo => DefaultConfig.Instance.CultureInfo!;
+    public ConfigOptions Options => DefaultConfig.Instance.Options;
+}

Robust.Benchmarks/EntityManager/AddRemoveComponentBenchmark.cs

@@ -0,0 +1,54 @@
+using BenchmarkDotNet.Attributes;
+using JetBrains.Annotations;
+using Robust.Shared.Analyzers;
+using Robust.Shared.GameObjects;
+using Robust.Shared.Map;
+using Robust.UnitTesting.Server;
+
+namespace Robust.Benchmarks.EntityManager;
+
+[Virtual]
+public class AddRemoveComponentBenchmark
+{
+    private ISimulation _simulation = default!;
+    private IEntityManager _entityManager = default!;
+
+    [UsedImplicitly]
+    [Params(1, 10, 100, 1000)]
+    public int N;
+
+    [GlobalSetup]
+    public void GlobalSetup()
+    {
+        _simulation = RobustServerSimulation
+            .NewSimulation()
+            .RegisterComponents(f => f.RegisterClass<A>())
+            .InitializeInstance();
+
+        _entityManager = _simulation.Resolve<IEntityManager>();
+
+        var coords = new MapCoordinates(0, 0, new MapId(1));
+        _simulation.AddMap(coords.MapId);
+
+        for (var i = 0; i < N; i++)
+        {
+            _entityManager.SpawnEntity(null, coords);
+        }
+    }
+
+    [Benchmark]
+    public void AddRemoveComponent()
+    {
+        for (var i = 2; i <= N+1; i++)
+        {
+            var uid = new EntityUid(i);
+            _entityManager.AddComponent<A>(uid);
+            _entityManager.RemoveComponent<A>(uid);
+        }
+    }
+
+    [ComponentProtoName("A")]
+    public sealed class A : Component
+    {
+    }
+}

Robust.Benchmarks/EntityManager/ComponentIndexBenchmark.cs

@@ -0,0 +1,225 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Reflection;
+using System.Threading;
+using BenchmarkDotNet.Attributes;
+using Robust.Shared.GameObjects;
+
+namespace Robust.Benchmarks.EntityManager;
+
+public class ComponentIndexBenchmark
+{
+    // Just a bunch of types to bloat the test lists.
+
+    private readonly CompIndexFetcher _compIndexFetcherDirect;
+    private readonly IFetcher _compIndexFetcher;
+    private readonly DictFetcher _dictFetcherDirect;
+    private readonly IFetcher _dictFetcher;
+
+
+    public ComponentIndexBenchmark()
+    {
+        _compIndexFetcherDirect = new CompIndexFetcher();
+        _compIndexFetcher = _compIndexFetcherDirect;
+        _dictFetcherDirect = new DictFetcher();
+        _dictFetcher = _dictFetcherDirect;
+    }
+
+    [GlobalSetup]
+    public void Setup()
+    {
+        var types = typeof(ComponentIndexBenchmark)
+            .GetNestedTypes(BindingFlags.NonPublic)
+            .Where(t => t.Name.StartsWith("TestType"))
+            .ToArray();
+
+        _compIndexFetcher.Init(types);
+        _dictFetcher.Init(types);
+    }
+
+    [Benchmark]
+    public int BenchCompIndex() => _compIndexFetcher.Get<TestType50>();
+
+    [Benchmark]
+    public int BenchDict() => _dictFetcher.Get<TestType50>();
+
+    [Benchmark]
+    public int BenchCompIndexDirect() => _compIndexFetcherDirect.Get<TestType50>();
+
+    [Benchmark]
+    public int BenchDictDirect() => _dictFetcherDirect.Get<TestType50>();
+
+    private static CompIdx ArrayIndexFor<T>() => CompArrayIndex<T>.Idx;
+
+    private static int _compIndexMaster = -1;
+
+    private static class CompArrayIndex<T>
+    {
+        // ReSharper disable once StaticMemberInGenericType
+        public static readonly CompIdx Idx = new(Interlocked.Increment(ref _compIndexMaster));
+    }
+
+    private static CompIdx GetCompIdIndex(Type type)
+    {
+        return (CompIdx)typeof(CompArrayIndex<>)
+            .MakeGenericType(type)
+            .GetField(nameof(CompArrayIndex<int>.Idx), BindingFlags.Static | BindingFlags.Public)!
+            .GetValue(null)!;
+    }
+
+    private interface IFetcher
+    {
+        void Init(Type[] types);
+
+        int Get<T>();
+    }
+
+    private sealed class CompIndexFetcher : IFetcher
+    {
+        private int[] _values = Array.Empty<int>();
+
+        public void Init(Type[] types)
+        {
+            var max = types.Max(t => GetCompIdIndex(t).Value);
+
+            _values = new int[max + 1];
+
+            var i = 0;
+            foreach (var type in types)
+            {
+                _values[GetCompIdIndex(type).Value] = i++;
+            }
+        }
+
+        public int Get<T>()
+        {
+            return _values[CompArrayIndex<T>.Idx.Value];
+        }
+    }
+
+    private sealed class DictFetcher : IFetcher
+    {
+        private readonly Dictionary<Type, int> _values = new();
+
+        public void Init(Type[] types)
+        {
+            var i = 0;
+            foreach (var type in types)
+            {
+                _values[type] = i++;
+            }
+        }
+
+        public int Get<T>()
+        {
+            return _values[typeof(T)];
+        }
+    }
+
+    // Just a bunch of types to pad the size of the arrays and such.
+
+    // @formatter:off
+    // ReSharper disable UnusedType.Local
+    private sealed class TestType1{}
+    private sealed class TestType2{}
+    private sealed class TestType3{}
+    private sealed class TestType4{}
+    private sealed class TestType5{}
+    private sealed class TestType6{}
+    private sealed class TestType7{}
+    private sealed class TestType8{}
+    private sealed class TestType9{}
+    private sealed class TestType10{}
+    private sealed class TestType11{}
+    private sealed class TestType12{}
+    private sealed class TestType13{}
+    private sealed class TestType14{}
+    private sealed class TestType15{}
+    private sealed class TestType16{}
+    private sealed class TestType17{}
+    private sealed class TestType18{}
+    private sealed class TestType19{}
+    private sealed class TestType20{}
+    private sealed class TestType21{}
+    private sealed class TestType22{}
+    private sealed class TestType23{}
+    private sealed class TestType24{}
+    private sealed class TestType25{}
+    private sealed class TestType26{}
+    private sealed class TestType27{}
+    private sealed class TestType28{}
+    private sealed class TestType29{}
+    private sealed class TestType30{}
+    private sealed class TestType31{}
+    private sealed class TestType32{}
+    private sealed class TestType33{}
+    private sealed class TestType34{}
+    private sealed class TestType35{}
+    private sealed class TestType36{}
+    private sealed class TestType37{}
+    private sealed class TestType38{}
+    private sealed class TestType39{}
+    private sealed class TestType40{}
+    private sealed class TestType41{}
+    private sealed class TestType42{}
+    private sealed class TestType43{}
+    private sealed class TestType44{}
+    private sealed class TestType45{}
+    private sealed class TestType46{}
+    private sealed class TestType47{}
+    private sealed class TestType48{}
+    private sealed class TestType49{}
+    private sealed class TestType50{}
+    private sealed class TestType51{}
+    private sealed class TestType52{}
+    private sealed class TestType53{}
+    private sealed class TestType54{}
+    private sealed class TestType55{}
+    private sealed class TestType56{}
+    private sealed class TestType57{}
+    private sealed class TestType58{}
+    private sealed class TestType59{}
+    private sealed class TestType60{}
+    private sealed class TestType61{}
+    private sealed class TestType62{}
+    private sealed class TestType63{}
+    private sealed class TestType64{}
+    private sealed class TestType65{}
+    private sealed class TestType66{}
+    private sealed class TestType67{}
+    private sealed class TestType68{}
+    private sealed class TestType69{}
+    private sealed class TestType70{}
+    private sealed class TestType71{}
+    private sealed class TestType72{}
+    private sealed class TestType73{}
+    private sealed class TestType74{}
+    private sealed class TestType75{}
+    private sealed class TestType76{}
+    private sealed class TestType77{}
+    private sealed class TestType78{}
+    private sealed class TestType79{}
+    private sealed class TestType80{}
+    private sealed class TestType81{}
+    private sealed class TestType82{}
+    private sealed class TestType83{}
+    private sealed class TestType84{}
+    private sealed class TestType85{}
+    private sealed class TestType86{}
+    private sealed class TestType87{}
+    private sealed class TestType88{}
+    private sealed class TestType89{}
+    private sealed class TestType90{}
+    private sealed class TestType91{}
+    private sealed class TestType92{}
+    private sealed class TestType93{}
+    private sealed class TestType94{}
+    private sealed class TestType95{}
+    private sealed class TestType96{}
+    private sealed class TestType97{}
+    private sealed class TestType98{}
+    private sealed class TestType99{}
+    // ReSharper restore UnusedType.Local
+    // @formatter:on
+}

Robust.Benchmarks/EntityManager/GetComponentBenchmark.cs

@@ -0,0 +1,61 @@
+using System;
+using BenchmarkDotNet.Attributes;
+using JetBrains.Annotations;
+using Robust.Shared.Analyzers;
+using Robust.Shared.GameObjects;
+using Robust.Shared.Map;
+using Robust.UnitTesting.Server;
+
+namespace Robust.Benchmarks.EntityManager;
+
+[Virtual]
+public class GetComponentBenchmark
+{
+    private ISimulation _simulation = default!;
+    private IEntityManager _entityManager = default!;
+
+    [UsedImplicitly]
+    [Params(1, 10, 100, 1000)]
+    public int N;
+
+    public A[] Comps = default!;
+
+    [GlobalSetup]
+    public void GlobalSetup()
+    {
+        _simulation = RobustServerSimulation
+            .NewSimulation()
+            .RegisterComponents(f => f.RegisterClass<A>())
+            .InitializeInstance();
+
+        _entityManager = _simulation.Resolve<IEntityManager>();
+
+        Comps = new A[N+2];
+
+        var coords = new MapCoordinates(0, 0, new MapId(1));
+        _simulation.AddMap(coords.MapId);
+
+        for (var i = 0; i < N; i++)
+        {
+            var uid = _entityManager.SpawnEntity(null, coords);
+            _entityManager.AddComponent<A>(uid);
+        }
+    }
+
+    [Benchmark]
+    public A[] GetComponent()
+    {
+        for (var i = 2; i <= N+1; i++)
+        {
+            Comps[i] = _entityManager.GetComponent<A>(new EntityUid(i));
+        }
+
+        // Return something so the JIT doesn't optimize out all the GetComponent calls.
+        return Comps;
+    }
+
+    [ComponentProtoName("A")]
+    public sealed class A : Component
+    {
+    }
+}

Robust.Benchmarks/EntityManager/SpawnDeleteEntityBenchmark.cs

@@ -0,0 +1,62 @@
+using BenchmarkDotNet.Attributes;
+using JetBrains.Annotations;
+using Robust.Shared.Analyzers;
+using Robust.Shared.GameObjects;
+using Robust.Shared.Map;
+using Robust.UnitTesting.Server;
+
+namespace Robust.Benchmarks.EntityManager;
+
+[Virtual]
+public class SpawnDeleteEntityBenchmark
+{
+    private ISimulation _simulation = default!;
+    private IEntityManager _entityManager = default!;
+
+    private MapCoordinates _mapCoords = MapCoordinates.Nullspace;
+    private EntityCoordinates _entCoords = EntityCoordinates.Invalid;
+
+    [UsedImplicitly]
+    [Params(1, 10, 100, 1000)]
+    public int N;
+
+    [GlobalSetup]
+    public void GlobalSetup()
+    {
+        _simulation = RobustServerSimulation
+            .NewSimulation()
+            .RegisterComponents(f => f.RegisterClass<A>())
+            .InitializeInstance();
+
+        _entityManager = _simulation.Resolve<IEntityManager>();
+
+        _mapCoords = new MapCoordinates(0, 0, new MapId(1));
+        var uid = _simulation.AddMap(_mapCoords.MapId);
+        _entCoords = new EntityCoordinates(uid, 0, 0);
+    }
+
+    [Benchmark(Baseline = true)]
+    public void SpawnDeleteEntityMapCoords()
+    {
+        for (var i = 0; i < N; i++)
+        {
+            var uid = _entityManager.SpawnEntity(null, _mapCoords);
+            _entityManager.DeleteEntity(uid);
+        }
+    }
+
+    [Benchmark]
+    public void SpawnDeleteEntityEntCoords()
+    {
+        for (var i = 0; i < N; i++)
+        {
+            var uid = _entityManager.SpawnEntity(null, _entCoords);
+            _entityManager.DeleteEntity(uid);
+        }
+    }
+
+    [ComponentProtoName("A")]
+    public sealed class A : Component
+    {
+    }
+}

Robust.Benchmarks/Exporters/SQLExporter.cs

@@ -0,0 +1,195 @@
+using System;
+using System.Collections.Generic;
+using System.ComponentModel.DataAnnotations.Schema;
+using System.Diagnostics.CodeAnalysis;
+using System.Linq;
+using System.Text.Json;
+using System.Text.Json.Serialization;
+using BenchmarkDotNet.Exporters;
+using BenchmarkDotNet.Loggers;
+using BenchmarkDotNet.Mathematics;
+using BenchmarkDotNet.Reports;
+using Microsoft.EntityFrameworkCore;
+using Microsoft.EntityFrameworkCore.Design;
+using Npgsql;
+using Npgsql.Internal;
+using Npgsql.Internal.TypeHandlers;
+using Npgsql.Internal.TypeHandling;
+
+namespace Robust.Benchmarks.Exporters;
+
+public sealed class SQLExporter : IExporter
+{
+    public static readonly IExporter Default = new SQLExporter();
+
+    private SQLExporter(){}
+
+    public void ExportToLog(Summary summary, ILogger logger)
+    {
+        Export(summary, logger);
+    }
+
+    public IEnumerable<string> ExportToFiles(Summary summary, ILogger consoleLogger)
+    {
+        Export(summary, consoleLogger);
+        return Array.Empty<string>();
+    }
+
+    private bool TryGetEnvironmentVariable(string name, ILogger logger, [NotNullWhen(true)] out string? value)
+    {
+        value = Environment.GetEnvironmentVariable(name);
+        if (value == null)
+            logger.WriteError($"ROBUST_BENCHMARKS_ENABLE_SQL is set, but {name} is missing.");
+        return value != null;
+    }
+
+    private void Export(Summary summary, ILogger logger)
+    {
+        if (!TryGetEnvironmentVariable("ROBUST_BENCHMARKS_SQL_ADDRESS", logger, out var address) ||
+            !TryGetEnvironmentVariable("ROBUST_BENCHMARKS_SQL_PORT", logger, out var rawPort) ||
+            !TryGetEnvironmentVariable("ROBUST_BENCHMARKS_SQL_USER", logger, out var user) ||
+            !TryGetEnvironmentVariable("ROBUST_BENCHMARKS_SQL_PASSWORD", logger, out var password) ||
+            !TryGetEnvironmentVariable("ROBUST_BENCHMARKS_SQL_DATABASE", logger, out var db) ||
+            !TryGetEnvironmentVariable("GITHUB_SHA", logger, out var gitHash))
+            return;
+
+        if (!int.TryParse(rawPort, out var port))
+        {
+            logger.WriteError("Failed parsing ROBUST_BENCHMARKS_SQL_PORT to int.");
+            return;
+        }
+
+        var builder = new DbContextOptionsBuilder<BenchmarkContext>();
+        var connectionString = new NpgsqlConnectionStringBuilder
+        {
+            Host = address,
+            Port = port,
+            Database = db,
+            Username = user,
+            Password = password
+        }.ConnectionString;
+        builder.UseNpgsql(connectionString);
+        using var ctx = new BenchmarkContext(builder.Options);
+        try
+        {
+            ctx.Database.OpenConnection();
+            var con = (NpgsqlConnection) ctx.Database.GetDbConnection();
+            con.TypeMapper.AddTypeResolverFactory(new JsonOverrideTypeHandlerResolverFactory(new JsonSerializerOptions
+            {
+                NumberHandling = JsonNumberHandling.AllowNamedFloatingPointLiterals
+            }));
+
+            ctx.Database.Migrate();
+            ctx.BenchmarkRuns.Add(BenchmarkRun.FromSummary(summary, gitHash));
+            ctx.SaveChanges();
+        }
+        finally
+        {
+            ctx.Dispose();
+        }
+    }
+
+    public string Name => "sql";
+}
+
+// https://github.com/npgsql/efcore.pg/issues/1107#issuecomment-945126627
+class JsonOverrideTypeHandlerResolverFactory : TypeHandlerResolverFactory
+{
+    private readonly JsonSerializerOptions _options;
+
+    public JsonOverrideTypeHandlerResolverFactory(JsonSerializerOptions options)
+        => _options = options;
+
+    public override TypeHandlerResolver Create(NpgsqlConnector connector)
+        => new JsonOverrideTypeHandlerResolver(connector, _options);
+
+    public override string? GetDataTypeNameByClrType(Type clrType)
+        => null;
+
+    public override TypeMappingInfo? GetMappingByDataTypeName(string dataTypeName)
+        => null;
+
+    class JsonOverrideTypeHandlerResolver : TypeHandlerResolver
+    {
+        readonly JsonHandler _jsonbHandler;
+
+        internal JsonOverrideTypeHandlerResolver(NpgsqlConnector connector, JsonSerializerOptions options)
+            => _jsonbHandler ??= new JsonHandler(
+                connector.DatabaseInfo.GetPostgresTypeByName("jsonb"),
+                connector.TextEncoding,
+                isJsonb: true,
+                options);
+
+        public override NpgsqlTypeHandler? ResolveByDataTypeName(string typeName)
+            => typeName == "jsonb" ? _jsonbHandler : null;
+
+        public override NpgsqlTypeHandler? ResolveByClrType(Type type)
+            // You can add any user-defined CLR types which you want mapped to jsonb
+            => type == typeof(JsonDocument) ? _jsonbHandler : null;
+
+        public override TypeMappingInfo? GetMappingByDataTypeName(string dataTypeName)
+            => null; // Let the built-in resolver do this
+    }
+}
+public sealed class DesignTimeContextFactoryPostgres : IDesignTimeDbContextFactory<BenchmarkContext>
+{
+    public BenchmarkContext CreateDbContext(string[] args)
+    {
+        var optionsBuilder = new DbContextOptionsBuilder<BenchmarkContext>();
+        optionsBuilder.UseNpgsql("Server=localhost");
+        return new BenchmarkContext(optionsBuilder.Options);
+    }
+}
+
+public class BenchmarkContext : DbContext
+{
+    public DbSet<BenchmarkRun> BenchmarkRuns { get; set; } = default!;
+
+    public BenchmarkContext() { }
+    public BenchmarkContext(DbContextOptions<BenchmarkContext> options) : base(options) { }
+}
+
+public class BenchmarkRun
+{
+    public int Id { get; set; }
+    public string GitHash { get; set; } = string.Empty;
+
+    [Column(TypeName = "timestamptz")]
+    public DateTime RunDate { get; set; }
+
+    public string Name { get; set; } = string.Empty;
+
+    [Column(TypeName = "jsonb")]
+    public BenchmarkRunReport[] Reports { get; set; } = Array.Empty<BenchmarkRunReport>();
+
+    public static BenchmarkRun FromSummary(Summary summary, string gitHash)
+    {
+        return new BenchmarkRun
+        {
+            Reports = summary.Reports.Select(r => new BenchmarkRunReport
+            {
+                Parameters = r.BenchmarkCase.Parameters.Items.Select(p => new BenchmarkRunParameter
+                {
+                    Name = p.Name,
+                    Value = p.Value
+                }).ToArray(),
+                Statistics = r.ResultStatistics
+            }).ToArray(),
+            Name = summary.BenchmarksCases.First().FolderInfo,
+            RunDate = DateTime.UtcNow,
+            GitHash = gitHash
+        };
+    }
+}
+
+public class BenchmarkRunReport
+{
+    public BenchmarkRunParameter[] Parameters { get; set; } = Array.Empty<BenchmarkRunParameter>();
+    public Statistics Statistics { get; set; } = default!;
+}
+
+public class BenchmarkRunParameter
+{
+    public string Name { get; set; } = string.Empty;
+    public object Value { get; set; } = default!;
+}

Robust.Benchmarks/Migrations/20220328231938_InitialCreate.Designer.cs

@@ -0,0 +1,55 @@
+// <auto-generated />
+using System;
+using Microsoft.EntityFrameworkCore;
+using Microsoft.EntityFrameworkCore.Infrastructure;
+using Microsoft.EntityFrameworkCore.Migrations;
+using Microsoft.EntityFrameworkCore.Storage.ValueConversion;
+using Npgsql.EntityFrameworkCore.PostgreSQL.Metadata;
+using Robust.Benchmarks.Exporters;
+
+#nullable disable
+
+namespace Robust.Benchmarks.Migrations
+{
+    [DbContext(typeof(BenchmarkContext))]
+    [Migration("20220328231938_InitialCreate")]
+    partial class InitialCreate
+    {
+        protected override void BuildTargetModel(ModelBuilder modelBuilder)
+        {
+#pragma warning disable 612, 618
+            modelBuilder
+                .HasAnnotation("ProductVersion", "6.0.0")
+                .HasAnnotation("Relational:MaxIdentifierLength", 63);
+
+            NpgsqlModelBuilderExtensions.UseIdentityByDefaultColumns(modelBuilder);
+
+            modelBuilder.Entity("Robust.Benchmarks.Exporters.BenchmarkRun", b =>
+                {
+                    b.Property<decimal>("Id")
+                        .ValueGeneratedOnAdd()
+                        .HasColumnType("numeric(20,0)");
+
+                    b.Property<string>("GitHash")
+                        .IsRequired()
+                        .HasColumnType("text");
+
+                    b.Property<string>("Name")
+                        .IsRequired()
+                        .HasColumnType("text");
+
+                    b.Property<BenchmarkRunReport[]>("Reports")
+                        .IsRequired()
+                        .HasColumnType("jsonb");
+
+                    b.Property<DateTime>("RunDate")
+                        .HasColumnType("Date");
+
+                    b.HasKey("Id");
+
+                    b.ToTable("BenchmarkRuns");
+                });
+#pragma warning restore 612, 618
+        }
+    }
+}

Robust.Benchmarks/Migrations/20220328231938_InitialCreate.cs

@@ -0,0 +1,35 @@
+using System;
+using Microsoft.EntityFrameworkCore.Migrations;
+using Robust.Benchmarks.Exporters;
+
+#nullable disable
+
+namespace Robust.Benchmarks.Migrations
+{
+    public partial class InitialCreate : Migration
+    {
+        protected override void Up(MigrationBuilder migrationBuilder)
+        {
+            migrationBuilder.CreateTable(
+                name: "BenchmarkRuns",
+                columns: table => new
+                {
+                    Id = table.Column<decimal>(type: "numeric(20,0)", nullable: false),
+                    GitHash = table.Column<string>(type: "text", nullable: false),
+                    RunDate = table.Column<DateTime>(type: "Date", nullable: false),
+                    Name = table.Column<string>(type: "text", nullable: false),
+                    Reports = table.Column<BenchmarkRunReport[]>(type: "jsonb", nullable: false)
+                },
+                constraints: table =>
+                {
+                    table.PrimaryKey("PK_BenchmarkRuns", x => x.Id);
+                });
+        }
+
+        protected override void Down(MigrationBuilder migrationBuilder)
+        {
+            migrationBuilder.DropTable(
+                name: "BenchmarkRuns");
+        }
+    }
+}

Robust.Benchmarks/Migrations/20220510131430_fix-pk.Designer.cs

@@ -0,0 +1,57 @@
+// <auto-generated />
+using System;
+using Microsoft.EntityFrameworkCore;
+using Microsoft.EntityFrameworkCore.Infrastructure;
+using Microsoft.EntityFrameworkCore.Migrations;
+using Microsoft.EntityFrameworkCore.Storage.ValueConversion;
+using Npgsql.EntityFrameworkCore.PostgreSQL.Metadata;
+using Robust.Benchmarks.Exporters;
+
+#nullable disable
+
+namespace Robust.Benchmarks.Migrations
+{
+    [DbContext(typeof(BenchmarkContext))]
+    [Migration("20220510131430_fix-pk")]
+    partial class fixpk
+    {
+        protected override void BuildTargetModel(ModelBuilder modelBuilder)
+        {
+#pragma warning disable 612, 618
+            modelBuilder
+                .HasAnnotation("ProductVersion", "6.0.0")
+                .HasAnnotation("Relational:MaxIdentifierLength", 63);
+
+            NpgsqlModelBuilderExtensions.UseIdentityByDefaultColumns(modelBuilder);
+
+            modelBuilder.Entity("Robust.Benchmarks.Exporters.BenchmarkRun", b =>
+                {
+                    b.Property<int>("Id")
+                        .ValueGeneratedOnAdd()
+                        .HasColumnType("integer");
+
+                    NpgsqlPropertyBuilderExtensions.UseIdentityByDefaultColumn(b.Property<int>("Id"));
+
+                    b.Property<string>("GitHash")
+                        .IsRequired()
+                        .HasColumnType("text");
+
+                    b.Property<string>("Name")
+                        .IsRequired()
+                        .HasColumnType("text");
+
+                    b.Property<BenchmarkRunReport[]>("Reports")
+                        .IsRequired()
+                        .HasColumnType("jsonb");
+
+                    b.Property<DateTime>("RunDate")
+                        .HasColumnType("timestamptz");
+
+                    b.HasKey("Id");
+
+                    b.ToTable("BenchmarkRuns");
+                });
+#pragma warning restore 612, 618
+        }
+    }
+}

Robust.Benchmarks/Migrations/20220510131430_fix-pk.cs

@@ -0,0 +1,51 @@
+using System;
+using Microsoft.EntityFrameworkCore.Migrations;
+using Npgsql.EntityFrameworkCore.PostgreSQL.Metadata;
+
+#nullable disable
+
+namespace Robust.Benchmarks.Migrations
+{
+    public partial class fixpk : Migration
+    {
+        protected override void Up(MigrationBuilder migrationBuilder)
+        {
+            migrationBuilder.AlterColumn<DateTime>(
+                name: "RunDate",
+                table: "BenchmarkRuns",
+                type: "timestamptz",
+                nullable: false,
+                oldClrType: typeof(DateTime),
+                oldType: "Date");
+
+            migrationBuilder.AlterColumn<int>(
+                name: "Id",
+                table: "BenchmarkRuns",
+                type: "integer",
+                nullable: false,
+                oldClrType: typeof(decimal),
+                oldType: "numeric(20,0)")
+                .Annotation("Npgsql:ValueGenerationStrategy", NpgsqlValueGenerationStrategy.IdentityByDefaultColumn);
+        }
+
+        protected override void Down(MigrationBuilder migrationBuilder)
+        {
+            migrationBuilder.AlterColumn<DateTime>(
+                name: "RunDate",
+                table: "BenchmarkRuns",
+                type: "Date",
+                nullable: false,
+                oldClrType: typeof(DateTime),
+                oldType: "timestamptz");
+
+            migrationBuilder.AlterColumn<decimal>(
+                name: "Id",
+                table: "BenchmarkRuns",
+                type: "numeric(20,0)",
+                nullable: false,
+                oldClrType: typeof(int),
+                oldType: "integer")
+                .OldAnnotation("Npgsql:ValueGenerationStrategy", NpgsqlValueGenerationStrategy.IdentityByDefaultColumn);
+        }
+    }
+}

Robust.Benchmarks/Migrations/BenchmarkContextModelSnapshot.cs

@@ -0,0 +1,55 @@
+// <auto-generated />
+using System;
+using Microsoft.EntityFrameworkCore;
+using Microsoft.EntityFrameworkCore.Infrastructure;
+using Microsoft.EntityFrameworkCore.Storage.ValueConversion;
+using Npgsql.EntityFrameworkCore.PostgreSQL.Metadata;
+using Robust.Benchmarks.Exporters;
+
+#nullable disable
+
+namespace Robust.Benchmarks.Migrations
+{
+    [DbContext(typeof(BenchmarkContext))]
+    partial class BenchmarkContextModelSnapshot : ModelSnapshot
+    {
+        protected override void BuildModel(ModelBuilder modelBuilder)
+        {
+#pragma warning disable 612, 618
+            modelBuilder
+                .HasAnnotation("ProductVersion", "6.0.0")
+                .HasAnnotation("Relational:MaxIdentifierLength", 63);
+
+            NpgsqlModelBuilderExtensions.UseIdentityByDefaultColumns(modelBuilder);
+
+            modelBuilder.Entity("Robust.Benchmarks.Exporters.BenchmarkRun", b =>
+                {
+                    b.Property<int>("Id")
+                        .ValueGeneratedOnAdd()
+                        .HasColumnType("integer");
+
+                    NpgsqlPropertyBuilderExtensions.UseIdentityByDefaultColumn(b.Property<int>("Id"));
+
+                    b.Property<string>("GitHash")
+                        .IsRequired()
+                        .HasColumnType("text");
+
+                    b.Property<string>("Name")
+                        .IsRequired()
+                        .HasColumnType("text");
+
+                    b.Property<BenchmarkRunReport[]>("Reports")
+                        .IsRequired()
+                        .HasColumnType("jsonb");
+
+                    b.Property<DateTime>("RunDate")
+                        .HasColumnType("timestamptz");
+
+                    b.HasKey("Id");
+
+                    b.ToTable("BenchmarkRuns");
+                });
+#pragma warning restore 612, 618
+        }
+    }
+}

Robust.Benchmarks/NumericsHelpers/AddBenchmark.cs

@@ -1,12 +1,17 @@
 using BenchmarkDotNet.Attributes;
+using Robust.Shared.Analyzers;
 
 namespace Robust.Benchmarks.NumericsHelpers
 {
+    [Virtual]
     public class AddBenchmark
     {
         [Params(32, 128)]
         public int N { get; set; }
 
+        [Params(1,2)]
+        public int T { get; set; }
+
         private float[] _inputA = default!;
         private float[] _inputB = default!;
         private float[] _output = default!;

Robust.Benchmarks/Program.cs

@@ -1,10 +1,12 @@
 using BenchmarkDotNet.Configs;
 using BenchmarkDotNet.Running;
 using System;
+using Robust.Benchmarks.Configs;
+using Robust.Benchmarks.Exporters;
 
 namespace Robust.Benchmarks
 {
-    internal class Program
+    internal static class Program
     {
         // --allCategories=ctg1,ctg2
         // --anyCategories=ctg1,ctg2
@@ -16,7 +18,8 @@ namespace Robust.Benchmarks
             Console.WriteLine("THE DEBUG BUILD IS ONLY GOOD FOR FIXING A CRASHING BENCHMARK\n");
             BenchmarkSwitcher.FromAssembly(typeof(Program).Assembly).Run(args, new DebugInProcessConfig());
 #else
-            BenchmarkSwitcher.FromAssembly(typeof(Program).Assembly).Run(args);
+            var config = Environment.GetEnvironmentVariable("ROBUST_BENCHMARKS_ENABLE_SQL") != null ? DefaultSQLConfig.Instance : null;
+            BenchmarkSwitcher.FromAssembly(typeof(Program).Assembly).Run(args, config);
 #endif
         }
     }

Robust.Benchmarks/Robust.Benchmarks.csproj

@@ -6,13 +6,20 @@
         <AppendTargetFrameworkToOutputPath>false</AppendTargetFrameworkToOutputPath>
         <OutputPath>../bin/Benchmarks</OutputPath>
         <OutputType>Exe</OutputType>
+        <NoWarn>RA0003</NoWarn>
     </PropertyGroup>
     <ItemGroup>
       <ProjectReference Include="..\Robust.Server\Robust.Server.csproj" />
       <ProjectReference Include="..\Robust.Shared\Robust.Shared.csproj" />
+      <ProjectReference Include="..\Robust.UnitTesting\Robust.UnitTesting.csproj" />
     </ItemGroup>
     <ItemGroup>
       <PackageReference Include="BenchmarkDotNet" Version="0.12.1" />
+      <PackageReference Include="Microsoft.EntityFrameworkCore.Design" Version="6.0.0">
+        <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
+        <PrivateAssets>all</PrivateAssets>
+      </PackageReference>
+      <PackageReference Include="Npgsql.EntityFrameworkCore.PostgreSQL" Version="6.0.4" />
     </ItemGroup>
     <Import Project="..\MSBuild\Robust.Engine.targets" />
 </Project>

Robust.Benchmarks/Serialization/BenchmarkIntSerializer.cs

@@ -1,7 +1,6 @@
 using System.Globalization;
 using Robust.Shared.IoC;
 using Robust.Shared.Serialization.Manager;
-using Robust.Shared.Serialization.Manager.Result;
 using Robust.Shared.Serialization.Markdown;
 using Robust.Shared.Serialization.Markdown.Validation;
 using Robust.Shared.Serialization.Markdown.Value;
@@ -9,7 +8,7 @@ using Robust.Shared.Serialization.TypeSerializers.Interfaces;
 
 namespace Robust.Benchmarks.Serialization
 {
-    public class BenchmarkIntSerializer : ITypeSerializer<int, ValueDataNode>
+    public sealed class BenchmarkIntSerializer : ITypeSerializer<int, ValueDataNode>
     {
         public ValidationNode Validate(ISerializationManager serializationManager, ValueDataNode node,
             IDependencyCollection dependencies, ISerializationContext? context = null)
@@ -19,10 +18,10 @@ namespace Robust.Benchmarks.Serialization
                 : new ErrorNode(node, $"Failed parsing int value: {node.Value}");
         }
 
-        public DeserializationResult Read(ISerializationManager serializationManager, ValueDataNode node,
-            IDependencyCollection dependencies, bool skipHook, ISerializationContext? context = null)
+        public int Read(ISerializationManager serializationManager, ValueDataNode node,
+            IDependencyCollection dependencies, bool skipHook, ISerializationContext? context = null, int _ = default)
         {
-            return new DeserializedValue<int>(int.Parse(node.Value, CultureInfo.InvariantCulture));
+            return int.Parse(node.Value, CultureInfo.InvariantCulture);
         }
 
         public DataNode Write(ISerializationManager serializationManager, int value, bool alwaysWrite = false,

Robust.Benchmarks/Serialization/Copy/SerializationCopyBenchmark.cs

@@ -2,6 +2,7 @@
 using System.Linq;
 using BenchmarkDotNet.Attributes;
 using Robust.Benchmarks.Serialization.Definitions;
+using Robust.Shared.Analyzers;
 using Robust.Shared.Serialization.Manager;
 using Robust.Shared.Serialization.Markdown;
 using Robust.Shared.Serialization.Markdown.Mapping;
@@ -13,6 +14,7 @@ using YamlDotNet.RepresentationModel;
 namespace Robust.Benchmarks.Serialization.Copy
 {
     [MemoryDiagnoser]
+    [Virtual]
     public class SerializationCopyBenchmark : SerializationBenchmark
     {
         public SerializationCopyBenchmark()
@@ -26,7 +28,7 @@ namespace Robust.Benchmarks.Serialization.Copy
 
             var seedMapping = yamlStream.Documents[0].RootNode.ToDataNodeCast<SequenceDataNode>().Cast<MappingDataNode>(0);
 
-            Seed = SerializationManager.ReadValueOrThrow<SeedDataDefinition>(seedMapping);
+            Seed = SerializationManager.Read<SeedDataDefinition>(seedMapping);
         }
 
         private const string String = "ABC";
@@ -44,25 +46,25 @@ namespace Robust.Benchmarks.Serialization.Copy
         [Benchmark]
         public string? CreateCopyString()
         {
-            return SerializationManager.CreateCopy(String);
+            return SerializationManager.Copy(String);
         }
 
         [Benchmark]
         public int? CreateCopyInteger()
         {
-            return SerializationManager.CreateCopy(Integer);
+            return SerializationManager.Copy(Integer);
         }
 
         [Benchmark]
         public DataDefinitionWithString? CreateCopyDataDefinitionWithString()
         {
-            return SerializationManager.CreateCopy(DataDefinitionWithString);
+            return SerializationManager.Copy(DataDefinitionWithString);
         }
 
         [Benchmark]
         public SeedDataDefinition? CreateCopySeedDataDefinition()
         {
-            return SerializationManager.CreateCopy(Seed);
+            return SerializationManager.Copy(Seed);
         }
 
         [Benchmark]

Robust.Benchmarks/Serialization/Definitions/BenchmarkFlags.cs

@@ -3,7 +3,7 @@ using Robust.Shared.Serialization;
 
 namespace Robust.Benchmarks.Serialization.Definitions
 {
-    public class BenchmarkFlags
+    public sealed class BenchmarkFlags
     {
         public const int Zero = 1 << 0;
         public const int ThirtyOne = 1 << 31;

Robust.Benchmarks/Serialization/Definitions/DataDefinitionWithString.cs

@@ -1,8 +1,10 @@
-using Robust.Shared.Serialization.Manager.Attributes;
+using Robust.Shared.Analyzers;
+using Robust.Shared.Serialization.Manager.Attributes;
 
 namespace Robust.Benchmarks.Serialization.Definitions
 {
     [DataDefinition]
+    [Virtual]
     public class DataDefinitionWithString
     {
         [DataField("string")]

Robust.Benchmarks/Serialization/Definitions/SeedDataDefinition.cs

@@ -11,7 +11,7 @@ namespace Robust.Benchmarks.Serialization.Definitions
     ///     Taken from content.
     /// </summary>
     [Prototype("seed")]
-    public class SeedDataDefinition : IPrototype
+    public sealed class SeedDataDefinition : IPrototype
     {
         public const string Prototype = @"
 - type: seed
@@ -19,6 +19,7 @@ namespace Robust.Benchmarks.Serialization.Definitions
   name: tobacco
   seedName: tobacco
   displayName: tobacco plant
+  plantRsi: Objects/Specific/Hydroponics/tobacco.rsi
   productPrototypes:
     - LeavesTobacco
   harvestRepeat: Repeat
@@ -36,7 +37,7 @@ namespace Robust.Benchmarks.Serialization.Definitions
       Max: 10
       PotencyDivisor: 10";
 
-        [DataField("id", required: true)] public string ID { get; set; } = default!;
+        [IdDataFieldAttribute] public string ID { get; set; } = default!;
 
         #region Tracking
         [DataField("name")] public string Name { get; set; } = string.Empty;

Robust.Benchmarks/Serialization/Initialize/SerializationInitializeBenchmark.cs

@@ -1,9 +1,11 @@
 using BenchmarkDotNet.Attributes;
+using Robust.Shared.Analyzers;
 using Robust.Shared.Serialization.Manager;
 
 namespace Robust.Benchmarks.Serialization.Initialize
 {
     [MemoryDiagnoser]
+    [Virtual]
     public class SerializationInitializeBenchmark : SerializationBenchmark
     {
         [IterationCleanup]

Robust.Benchmarks/Serialization/Read/SerializationReadBenchmark.cs

@@ -1,7 +1,7 @@
 using System.IO;
 using BenchmarkDotNet.Attributes;
 using Robust.Benchmarks.Serialization.Definitions;
-using Robust.Shared.Serialization.Manager.Result;
+using Robust.Shared.Analyzers;
 using Robust.Shared.Serialization.Markdown;
 using Robust.Shared.Serialization.Markdown.Mapping;
 using Robust.Shared.Serialization.Markdown.Sequence;
@@ -12,6 +12,7 @@ using YamlDotNet.RepresentationModel;
 namespace Robust.Benchmarks.Serialization.Read
 {
     [MemoryDiagnoser]
+    [Virtual]
     public class SerializationReadBenchmark : SerializationBenchmark
     {
         public SerializationReadBenchmark()
@@ -40,32 +41,32 @@ namespace Robust.Benchmarks.Serialization.Read
         private ValueDataNode FlagThirtyOne { get; } = new("ThirtyOne");
 
         [Benchmark]
-        public string? ReadString()
+        public string ReadString()
         {
-            return SerializationManager.ReadValue<string>(StringNode);
+            return SerializationManager.Read<string>(StringNode);
         }
 
         [Benchmark]
-        public int? ReadInteger()
+        public int ReadInteger()
         {
-            return SerializationManager.ReadValue<int>(IntNode);
+            return SerializationManager.Read<int>(IntNode);
         }
 
         [Benchmark]
-        public DataDefinitionWithString? ReadDataDefinitionWithString()
+        public DataDefinitionWithString ReadDataDefinitionWithString()
         {
-            return SerializationManager.ReadValue<DataDefinitionWithString>(StringDataDefNode);
+            return SerializationManager.Read<DataDefinitionWithString>(StringDataDefNode);
         }
 
         [Benchmark]
-        public SeedDataDefinition? ReadSeedDataDefinition()
+        public SeedDataDefinition ReadSeedDataDefinition()
         {
-            return SerializationManager.ReadValue<SeedDataDefinition>(SeedNode);
+            return SerializationManager.Read<SeedDataDefinition>(SeedNode);
         }
 
         [Benchmark]
         [BenchmarkCategory("flag")]
-        public DeserializationResult ReadFlagZero()
+        public object? ReadFlagZero()
         {
             return SerializationManager.ReadWithTypeSerializer(
                 typeof(int),
@@ -75,7 +76,7 @@ namespace Robust.Benchmarks.Serialization.Read
 
         [Benchmark]
         [BenchmarkCategory("flag")]
-        public DeserializationResult ReadThirtyOne()
+        public object? ReadThirtyOne()
         {
             return SerializationManager.ReadWithTypeSerializer(
                 typeof(int),
@@ -85,7 +86,7 @@ namespace Robust.Benchmarks.Serialization.Read
 
         [Benchmark]
         [BenchmarkCategory("customTypeSerializer")]
-        public DeserializationResult ReadIntegerCustomSerializer()
+        public object? ReadIntegerCustomSerializer()
         {
             return SerializationManager.ReadWithTypeSerializer(
                 typeof(int),

Robust.Benchmarks/Serialization/SerializationArrayBenchmark.cs

@@ -1,5 +1,6 @@
 using BenchmarkDotNet.Attributes;
 using Robust.Benchmarks.Serialization.Definitions;
+using Robust.Shared.Analyzers;
 using Robust.Shared.Serialization.Markdown.Mapping;
 using Robust.Shared.Serialization.Markdown.Sequence;
 using Robust.Shared.Serialization.Markdown.Value;
@@ -7,6 +8,7 @@ using Robust.Shared.Serialization.Markdown.Value;
 namespace Robust.Benchmarks.Serialization
 {
     [MemoryDiagnoser]
+    [Virtual]
     public class SerializationArrayBenchmark : SerializationBenchmark
     {
         public SerializationArrayBenchmark()
@@ -44,84 +46,84 @@ namespace Robust.Benchmarks.Serialization
         [BenchmarkCategory("read")]
         public string[]? ReadEmptyString()
         {
-            return SerializationManager.ReadValue<string[]>(EmptyNode);
+            return SerializationManager.Read<string[]>(EmptyNode);
         }
 
         [Benchmark]
         [BenchmarkCategory("read")]
         public string[]? ReadOneString()
         {
-            return SerializationManager.ReadValue<string[]>(OneIntNode);
+            return SerializationManager.Read<string[]>(OneIntNode);
         }
 
         [Benchmark]
         [BenchmarkCategory("read")]
         public string[]? ReadTenStrings()
         {
-            return SerializationManager.ReadValue<string[]>(TenIntsNode);
+            return SerializationManager.Read<string[]>(TenIntsNode);
         }
 
         [Benchmark]
         [BenchmarkCategory("read")]
         public int[]? ReadEmptyInt()
         {
-            return SerializationManager.ReadValue<int[]>(EmptyNode);
+            return SerializationManager.Read<int[]>(EmptyNode);
         }
 
         [Benchmark]
         [BenchmarkCategory("read")]
         public int[]? ReadOneInt()
         {
-            return SerializationManager.ReadValue<int[]>(OneIntNode);
+            return SerializationManager.Read<int[]>(OneIntNode);
         }
 
         [Benchmark]
         [BenchmarkCategory("read")]
         public int[]? ReadTenInts()
         {
-            return SerializationManager.ReadValue<int[]>(TenIntsNode);
+            return SerializationManager.Read<int[]>(TenIntsNode);
         }
 
         [Benchmark]
         [BenchmarkCategory("read")]
         public DataDefinitionWithString[]? ReadEmptyStringDataDef()
         {
-            return SerializationManager.ReadValue<DataDefinitionWithString[]>(EmptyNode);
+            return SerializationManager.Read<DataDefinitionWithString[]>(EmptyNode);
         }
 
         [Benchmark]
         [BenchmarkCategory("read")]
         public DataDefinitionWithString[]? ReadOneStringDataDef()
         {
-            return SerializationManager.ReadValue<DataDefinitionWithString[]>(OneStringDefNode);
+            return SerializationManager.Read<DataDefinitionWithString[]>(OneStringDefNode);
         }
 
         [Benchmark]
         [BenchmarkCategory("read")]
         public DataDefinitionWithString[]? ReadTenStringDataDefs()
         {
-            return SerializationManager.ReadValue<DataDefinitionWithString[]>(TenStringDefsNode);
+            return SerializationManager.Read<DataDefinitionWithString[]>(TenStringDefsNode);
         }
 
         [Benchmark]
         [BenchmarkCategory("read")]
         public SealedDataDefinitionWithString[]? ReadEmptySealedStringDataDef()
         {
-            return SerializationManager.ReadValue<SealedDataDefinitionWithString[]>(EmptyNode);
+            return SerializationManager.Read<SealedDataDefinitionWithString[]>(EmptyNode);
         }
 
         [Benchmark]
         [BenchmarkCategory("read")]
         public SealedDataDefinitionWithString[]? ReadOneSealedStringDataDef()
         {
-            return SerializationManager.ReadValue<SealedDataDefinitionWithString[]>(OneStringDefNode);
+            return SerializationManager.Read<SealedDataDefinitionWithString[]>(OneStringDefNode);
         }
 
         [Benchmark]
         [BenchmarkCategory("read")]
         public SealedDataDefinitionWithString[]? ReadTenSealedStringDataDefs()
         {
-            return SerializationManager.ReadValue<SealedDataDefinitionWithString[]>(TenStringDefsNode);
+            return SerializationManager.Read<SealedDataDefinitionWithString[]>(TenStringDefsNode);
         }
     }
 }

Robust.Benchmarks/Serialization/Write/SerializationWriteBenchmark.cs

@@ -2,6 +2,7 @@
 using System.IO;
 using BenchmarkDotNet.Attributes;
 using Robust.Benchmarks.Serialization.Definitions;
+using Robust.Shared.Analyzers;
 using Robust.Shared.Serialization.Manager;
 using Robust.Shared.Serialization.Markdown;
 using Robust.Shared.Serialization.Markdown.Mapping;
@@ -13,6 +14,7 @@ using YamlDotNet.RepresentationModel;
 namespace Robust.Benchmarks.Serialization.Write
 {
     [MemoryDiagnoser]
+    [Virtual]
     public class SerializationWriteBenchmark : SerializationBenchmark
     {
         public SerializationWriteBenchmark()
@@ -26,7 +28,7 @@ namespace Robust.Benchmarks.Serialization.Write
 
             var seedMapping = yamlStream.Documents[0].RootNode.ToDataNodeCast<SequenceDataNode>().Cast<MappingDataNode>(0);
 
-            Seed = SerializationManager.ReadValueOrThrow<SeedDataDefinition>(seedMapping);
+            Seed = SerializationManager.Read<SeedDataDefinition>(seedMapping);
         }
 
         private const string String = "ABC";

Robust.Benchmarks/add-migration.ps1

@@ -0,0 +1,11 @@
+#!/usr/bin/env pwsh
+
+param([String]$name)
+
+if ($name -eq "")
+{
+    Write-Error "must specify migration name"
+    exit
+}
+
+dotnet ef migrations add --context BenchmarkContext -o Migrations $name

Robust.Benchmarks/add-migration.sh

@@ -0,0 +1,8 @@
+#!/usr/bin/env bash
+
+if [ -z "$1" ] ; then
+    echo "Must specify migration name"
+    exit 1
+fi
+
+dotnet ef migrations add --context BenchmarkContext -o Migrations "$1"

Robust.Client.Injectors/Robust.Client.Injectors.csproj

@@ -6,7 +6,7 @@
     </PropertyGroup>
 
     <ItemGroup>
-      <PackageReference Include="Microsoft.Build.Framework" Version="16.8.0" />
+      <PackageReference Include="Microsoft.Build.Framework" Version="17.0.0" />
       <PackageReference Include="Mono.Cecil" Version="0.11.3" />
       <PackageReference Include="Pidgin" Version="2.5.0" />
     </ItemGroup>

Robust.Client.Injectors/XamlCompiler.cs

@@ -76,7 +76,7 @@ namespace Robust.Build.Tasks
                 },
                 ContentAttributes =
                 {
-                    typeSystem.GetType("Robust.Client.UserInterface.XAML.ContentAttribute")
+                    typeSystem.GetType("Avalonia.Metadata.ContentAttribute")
                 },
                 UsableDuringInitializationAttributes =
                 {

Robust.Client.NameGenerator/Robust.Client.NameGenerator.csproj

@@ -5,8 +5,8 @@
     </PropertyGroup>
 
   <ItemGroup>
-    <PackageReference Include="Microsoft.CodeAnalysis.CSharp" Version="3.8.0" PrivateAssets="all" />
-    <PackageReference Include="Microsoft.CodeAnalysis.Analyzers" Version="3.3.2" PrivateAssets="all" />
+    <PackageReference Include="Microsoft.CodeAnalysis.CSharp" Version="4.0.1" PrivateAssets="all" />
+    <PackageReference Include="Microsoft.CodeAnalysis.Analyzers" Version="3.3.3" PrivateAssets="all" />
   </ItemGroup>
 
   <ItemGroup>

Robust.Client.WebView/Cef/Program.cs

@@ -1,7 +1,4 @@
 using System;
-using System.IO;
-using System.Runtime.InteropServices;
-using Robust.Shared.ContentPack;
 using Xilium.CefGlue;
 
 namespace Robust.Client.WebView.Cef
@@ -19,24 +16,11 @@ namespace Robust.Client.WebView.Cef
                 Array.Copy(args, 0, argv, 1, args.Length);
                 argv[0] = "-";
             }
-/* 
-            if (OperatingSystem.IsLinux())
-            {
-                // Chromium tries to load libEGL.so and libGLESv2.so relative to the process executable on Linux.
-                // (Compared to Windows where it is relative to Chromium's *module*)
-                // There is a TODO "is this correct?" in the Chromium code for this.
-                // Great.
-                
-                //CopyDllToExecutableDir("libEGL.so");
-                //CopyDllToExecutableDir("libGLESv2.so");
 
-                // System.Threading.Thread.Sleep(200000);
-            }
- */
             var mainArgs = new CefMainArgs(argv);
 
             // This will block executing until the subprocess is shut down.
-            var code = CefRuntime.ExecuteProcess(mainArgs, null, IntPtr.Zero);
+            var code = CefRuntime.ExecuteProcess(mainArgs, new RobustCefApp(), IntPtr.Zero);
 
             if (code != 0)
             {
@@ -45,44 +29,5 @@ namespace Robust.Client.WebView.Cef
 
             return code;
         }
-
-/*         private static void CopyDllToExecutableDir(string dllName)
-        {
-            var executableDir = PathHelpers.GetExecutableDirectory();
-            var targetPath = Path.Combine(executableDir, dllName);
-            if (File.Exists(targetPath))
-                return;
-
-            // Find source file.
-            string? srcFile = null;
-            foreach (var searchDir in WebViewManagerCef.NativeDllSearchDirectories())
-            {
-                var searchPath = Path.Combine(searchDir, dllName);
-                if (File.Exists(searchPath))
-                {
-                    srcFile = searchPath;
-                    break;
-                }
-            }
-
-            if (srcFile == null)
-                return;
-
-            for (var i = 0; i < 5; i++)
-            {
-                try
-                {
-                    if (File.Exists(targetPath))
-                        return;
-
-                    File.Copy(srcFile, targetPath);
-                    return;
-                }
-                catch 
-                {
-                    // Catching race condition lock errors and stuff I guess.
-                }
-            }
-        } */
     }
 }

Robust.Client.WebView/Cef/RobustCefApp.cs

@@ -5,7 +5,7 @@ using Xilium.CefGlue;
 
 namespace Robust.Client.WebView.Cef
 {
-    internal class RobustCefApp : CefApp
+    internal sealed class RobustCefApp : CefApp
     {
         private readonly BrowserProcessHandler _browserProcessHandler = new();
         private readonly RenderProcessHandler _renderProcessHandler = new();
@@ -24,12 +24,12 @@ namespace Robust.Client.WebView.Cef
         {
             // Disable zygote on Linux.
             commandLine.AppendSwitch("--no-zygote");
-            
+
             // Work around https://bitbucket.org/chromiumembedded/cef/issues/3213/ozone-egl-initialization-does-not-have
             // Desktop GL force makes Chromium not try to load its own ANGLE/Swiftshader so load paths aren't problematic.
             if (OperatingSystem.IsLinux())
                 commandLine.AppendSwitch("--use-gl", "desktop");
-            
+
             // commandLine.AppendSwitch("--single-process");
 
             //commandLine.AppendSwitch("--disable-gpu");
@@ -43,12 +43,18 @@ namespace Robust.Client.WebView.Cef
                 Logger.Debug($"{commandLine}");
         }
 
-        private class BrowserProcessHandler : CefBrowserProcessHandler
+        protected override void OnRegisterCustomSchemes(CefSchemeRegistrar registrar)
+        {
+            registrar.AddCustomScheme("res", CefSchemeOptions.Secure | CefSchemeOptions.Standard);
+            registrar.AddCustomScheme("usr", CefSchemeOptions.Secure | CefSchemeOptions.Standard);
+        }
+
+        private sealed class BrowserProcessHandler : CefBrowserProcessHandler
         {
         }
 
         // TODO CEF: Research - Is this even needed?
-        private class RenderProcessHandler : CefRenderProcessHandler
+        private sealed class RenderProcessHandler : CefRenderProcessHandler
         {
         }
     }

Robust.Client.WebView/Cef/RobustCefClient.cs

@@ -3,7 +3,7 @@ using Xilium.CefGlue;
 namespace Robust.Client.WebView.Cef
 {
     // Simple CEF client.
-    internal class RobustCefClient : CefClient
+    internal sealed class RobustCefClient : CefClient
     {
         private readonly CefRenderHandler _renderHandler;
         private readonly CefRequestHandler _requestHandler;

Robust.Client.WebView/Cef/RobustRequestHandler.cs

@@ -57,6 +57,14 @@ namespace Robust.Client.WebView.Cef
             string requestInitiator,
             ref bool disableDefaultHandling)
         {
+            var url = new Uri(request.Url);
+            if (url.Scheme == "file")
+            {
+                // Deny file:// access.
+                disableDefaultHandling = true;
+                return null;
+            }
+
             lock (_resourceRequestHandlers)
             {
                 _sawmill.Debug($"HANDLING REQUEST: {request.Url}");
@@ -113,7 +121,7 @@ namespace Robust.Client.WebView.Cef
                 CefFrame frame,
                 CefRequest request)
             {
-                return null;
+                return new CookieHandler();
             }
 
             protected override CefResourceHandler GetResourceHandler(
@@ -124,5 +132,18 @@ namespace Robust.Client.WebView.Cef
                 return _handler;
             }
         }
+
+        private sealed class CookieHandler : CefCookieAccessFilter
+        {
+            protected override bool CanSendCookie(CefBrowser browser, CefFrame frame, CefRequest request, CefCookie cookie)
+            {
+                return true;
+            }
+
+            protected override bool CanSaveCookie(CefBrowser browser, CefFrame frame, CefRequest request, CefResponse response, CefCookie cookie)
+            {
+                return true;
+            }
+        }
     }
 }

Robust.Client.WebView/Cef/WebViewManagerCef.Mime.cs

@@ -0,0 +1,75 @@
+using System.Collections.Generic;
+using System.Diagnostics.CodeAnalysis;
+using Robust.Shared.Utility;
+
+namespace Robust.Client.WebView.Cef;
+
+internal sealed partial class WebViewManagerCef
+{
+    // Loosely based on:
+    // https://developer.mozilla.org/en-US/docs/Web/HTTP/Basics_of_HTTP/MIME_types/Common_types
+    private readonly Dictionary<string, string> _resourceMimeTypes = new()
+    {
+        { "aac", "audio/aac" },
+        { "avif", "image/avif" },
+        { "avi", "video/x-msvideo" },
+        { "bmp", "image/bmp" },
+        { "css", "text/css" },
+        { "gif", "image/gif" },
+        { "htm", "text/html" },
+        { "html", "text/html" },
+        { "ico", "image/vnd.microsoft.icon" },
+        { "jpeg", "image/jpeg" },
+        { "jpg", "image/jpeg" },
+        { "js", "text/javascript" },
+        { "json", "application/json" },
+        { "jsonld", "application/ld+json" },
+        { "midi", "audio/midi" },
+        { "mid", "audio/midi" },
+        { "mjs", "text/javascript" },
+        { "mp3", "audio/mpeg" },
+        { "mp4", "video/mp4" },
+        { "mpeg", "video/mpeg" },
+        { "oga", "audio/ogg" },
+        { "ogg", "audio/ogg" },
+        { "ogv", "video/ogg" },
+        { "ogx", "application/ogg" },
+        { "opus", "audio/opus" },
+        { "otf", "font/otf" },
+        { "png", "image/png" },
+        { "pdf", "application/pdf" },
+        { "svg", "image/svg+xml" },
+        { "tiff", "image/tiff" },
+        { "tif", "image/tiff" },
+        { "ts", "video/mp2t" },
+        { "ttf", "font/ttf" },
+        { "txt", "text/plain" },
+        { "wav", "audio/wav" },
+        { "weba", "audio/webm" },
+        { "webm", "video/webm" },
+        { "webp", "image/webp" },
+        { "woff", "font/woff" },
+        { "woff2", "font/woff2" },
+        { "xhtml", "application/xhtml+xml" },
+        { "xml", "application/xml" },
+        { "zip", "application/zip" },
+    };
+
+    public void SetResourceMimeType(string extension, string mimeType)
+    {
+        DebugTools.Assert(!extension.StartsWith("."), "SetResourceMimeType extension must not include starting dot.");
+
+        lock (_resourceMimeTypes)
+        {
+            _resourceMimeTypes[extension] = mimeType;
+        }
+    }
+
+    public bool TryGetResourceMimeType(string extension, [NotNullWhen(true)] out string? mimeType)
+    {
+        lock (_resourceMimeTypes)
+        {
+            return _resourceMimeTypes.TryGetValue(extension, out mimeType);
+        }
+    }
+}

Robust.Client.WebView/Cef/WebViewManagerCef.cs

@@ -1,24 +1,41 @@
 using System;
 using System.IO;
+using System.Net;
+using System.Reflection;
+using System.Text;
+using Robust.Client.Console;
+using Robust.Shared.Configuration;
 using Robust.Shared.ContentPack;
 using Robust.Shared.IoC;
+using Robust.Shared.Localization;
 using Robust.Shared.Log;
 using Robust.Shared.Prototypes;
+using Robust.Shared.Utility;
 using Xilium.CefGlue;
 
 namespace Robust.Client.WebView.Cef
 {
-    internal partial class WebViewManagerCef : IWebViewManagerImpl
+    internal sealed partial class WebViewManagerCef : IWebViewManagerImpl
     {
+        private static readonly string BasePath = Path.GetDirectoryName(Assembly.GetExecutingAssembly().Location!)!;
+
         private CefApp _app = default!;
 
         [Dependency] private readonly IDependencyCollection _dependencyCollection = default!;
         [Dependency] private readonly IPrototypeManager _prototypeManager = default!;
+        [Dependency] private readonly IResourceManagerInternal _resourceManager = default!;
+        [Dependency] private readonly IClientConsoleHost _consoleHost = default!;
+        [Dependency] private readonly IConfigurationManager _cfg = default!;
 
         public void Initialize()
         {
             IoCManager.Instance!.InjectDependencies(this, oneOff: true);
 
+            _consoleHost.RegisterCommand("flushcookies", Loc.GetString("cmd-flushcookies-desc"), Loc.GetString("cmd-flushcookies-help"), (_, _, _) =>
+            {
+                CefCookieManager.GetGlobal(null).FlushStore(null);
+            });
+
             string subProcessName;
             if (OperatingSystem.IsWindows())
                 subProcessName = "Robust.Client.WebView.exe";
@@ -27,7 +44,7 @@ namespace Robust.Client.WebView.Cef
             else
                 throw new NotSupportedException("Unsupported platform for CEF!");
 
-            var subProcessPath = PathHelpers.ExecutableRelativeFile(subProcessName);
+            var subProcessPath = Path.Combine(BasePath, subProcessName);
             var cefResourcesPath = LocateCefResources();
 
             // System.Console.WriteLine(AppContext.GetData("NATIVE_DLL_SEARCH_DIRECTORIES"));
@@ -35,6 +52,10 @@ namespace Robust.Client.WebView.Cef
             if (cefResourcesPath == null)
                 throw new InvalidOperationException("Unable to locate cef_resources directory!");
 
+            var cachePath = "";
+            if (_resourceManager.UserData is WritableDirProvider userData)
+                cachePath = userData.GetFullPath(new ResourcePath("/cef_cache"));
+
             var settings = new CefSettings()
             {
                 WindowlessRenderingEnabled = true, // So we can render to our UI controls.
@@ -44,6 +65,8 @@ namespace Robust.Client.WebView.Cef
                 LocalesDirPath = Path.Combine(cefResourcesPath, "locales"),
                 ResourcesDirPath = cefResourcesPath,
                 RemoteDebuggingPort = 9222,
+                CookieableSchemesList = "usr,res",
+                CachePath = cachePath,
             };
 
             Logger.Info($"CEF Version: {CefRuntime.ChromeVersion}");
@@ -56,11 +79,17 @@ namespace Robust.Client.WebView.Cef
             // TODO CEF: After this point, debugging breaks. No, literally. My client crashes but ONLY with the debugger.
             // I have tried using the DEBUG and RELEASE versions of libcef.so, stripped or non-stripped...
             // And nothing seemed to work. Odd.
+
+            if (_cfg.GetCVar(WCVars.WebResProtocol))
+            {
+                var handler = new ResourceSchemeFactoryHandler(this, _resourceManager, Logger.GetSawmill("web.res"));
+                CefRuntime.RegisterSchemeHandlerFactory("res", "", handler);
+            }
         }
 
         private static string? LocateCefResources()
         {
-            if (ProbeDir(PathHelpers.GetExecutableDirectory(), out var path))
+            if (ProbeDir(BasePath, out var path))
                 return path;
 
 
@@ -99,5 +128,48 @@ namespace Robust.Client.WebView.Cef
         {
             CefRuntime.Shutdown();
         }
+
+        private sealed class ResourceSchemeFactoryHandler : CefSchemeHandlerFactory
+        {
+            private readonly WebViewManagerCef _parent;
+            private readonly IResourceManager _resourceManager;
+            private readonly ISawmill _sawmill;
+
+            public ResourceSchemeFactoryHandler(
+                WebViewManagerCef parent,
+                IResourceManager resourceManager,
+                ISawmill sawmill)
+            {
+                _parent = parent;
+                _resourceManager = resourceManager;
+                _sawmill = sawmill;
+            }
+
+            protected override CefResourceHandler Create(
+                CefBrowser browser,
+                CefFrame frame,
+                string schemeName,
+                CefRequest request)
+            {
+                var uri = new Uri(request.Url);
+
+                _sawmill.Debug($"HANDLING: {request.Url}");
+
+                var resourcePath = new ResourcePath(uri.AbsolutePath);
+                if (_resourceManager.TryContentFileRead(resourcePath, out var stream))
+                {
+                    if (!_parent.TryGetResourceMimeType(resourcePath.Extension, out var mime))
+                        mime = "application/octet-stream";
+
+                    return new RequestResultStream(stream, mime, HttpStatusCode.OK).MakeHandler();
+                }
+
+                var notFoundStream = new MemoryStream();
+                notFoundStream.Write(Encoding.UTF8.GetBytes("Not found"));
+                notFoundStream.Position = 0;
+
+                return new RequestResultStream(notFoundStream, "text/plain", HttpStatusCode.NotFound).MakeHandler();
+            }
+        }
     }
 }

Robust.Client.WebView/Headless/WebViewManagerHeadless.cs

@@ -1,4 +1,5 @@
 using System;
+using System.Diagnostics.CodeAnalysis;
 using Robust.Client.Graphics;
 using Robust.Client.UserInterface;
 
@@ -11,6 +12,17 @@ namespace Robust.Client.WebView.Headless
             return new WebViewWindowDummy();
         }
 
+        public void SetResourceMimeType(string extension, string mimeType)
+        {
+            // Nop
+        }
+
+        public bool TryGetResourceMimeType(string extension, [NotNullWhen(true)] out string? mimeType)
+        {
+            mimeType = null;
+            return false;
+        }
+
         public IWebViewControlImpl MakeControlImpl(WebViewControl owner)
         {
             return new WebViewControlImplDummy();

Robust.Client.WebView/IWebViewManager.cs

@@ -1,7 +1,40 @@
-namespace Robust.Client.WebView
+using System.Diagnostics.CodeAnalysis;
+
+namespace Robust.Client.WebView
 {
     public interface IWebViewManager
     {
         IWebViewWindow CreateBrowserWindow(BrowserWindowCreateParameters createParams);
+
+        /// <summary>
+        /// Overrides file extension -> mime type mappings for the <c>res://</c> protocol.
+        /// </summary>
+        /// <remarks>
+        /// <para>
+        /// The built-in <c>res://</c> protocol needs to guess MIME types to report to CEF when resolving files.
+        /// A limited set of extensions have pre-set MIME types in the engine.
+        /// This method allows you to replace or add entries if need be.
+        /// </para>
+        /// <para>
+        /// This method is thread safe.
+        /// </para>
+        /// </remarks>
+        /// <param name="extension">
+        /// The extension to specify the MIME type for.
+        /// The argument must not include the starting "." of the file extension.
+        /// </param>
+        /// <param name="mimeType">The mime type for this file extension.</param>
+        /// <seealso cref="TryGetResourceMimeType"/>
+        void SetResourceMimeType(string extension, string mimeType);
+
+        /// <summary>
+        /// Tries to resolve an entry from the <see cref="SetResourceMimeType"/> list.
+        /// </summary>
+        /// <remarks>
+        /// <para>
+        /// This method is thread safe.
+        /// </para>
+        /// </remarks>
+        bool TryGetResourceMimeType(string extension, [NotNullWhen(true)] out string? mimeType);
     }
 }

Robust.Client.WebView/Robust.Client.WebView.csproj

@@ -14,8 +14,7 @@
 
   <ItemGroup>
     <PackageReference Include="JetBrains.Annotations" Version="2020.3.0" />
-    <PackageReference Include="System.Drawing.Common" Version="5.0.2" />
-    <PackageReference Include="Robust.Natives.Cef" Version="95.7.14" />
+    <PackageReference Include="Robust.Natives.Cef" Version="102.0.9" />
   </ItemGroup>
 
   <ItemGroup>

Robust.Client.WebView/WCVars.cs

@@ -0,0 +1,17 @@
+using Robust.Shared.Configuration;
+
+namespace Robust.Client.WebView;
+
+// ReSharper disable once InconsistentNaming
+/// <summary>
+/// CVars for <c>Robust.Client.WebView</c>
+/// </summary>
+[CVarDefs]
+public static class WCVars
+{
+    /// <summary>
+    /// Enable the <c>res://</c> protocol inside WebView browsers, allowing access to the Robust resources.
+    /// </summary>
+    public static readonly CVarDef<bool> WebResProtocol =
+        CVarDef.Create("web.res_protocol", true, CVar.CLIENTONLY);
+}

Robust.Client.WebView/WebViewManager.cs

@@ -1,7 +1,9 @@
-using Robust.Client.WebView;
+using System.Diagnostics.CodeAnalysis;
+using Robust.Client.WebView;
 using Robust.Client.WebView.Cef;
 using Robust.Client.WebView.Headless;
 using Robust.Client.WebViewHook;
+using Robust.Shared.Configuration;
 using Robust.Shared.IoC;
 using Robust.Shared.Utility;
 
@@ -17,6 +19,9 @@ namespace Robust.Client.WebView
         {
             DebugTools.Assert(_impl == null, "WebViewManager has already been initialized!");
 
+            var cfg = IoCManager.Resolve<IConfigurationManagerInternal>();
+            cfg.LoadCVarsFromAssembly(typeof(WebViewManager).Assembly);
+
             IoCManager.RegisterInstance<IWebViewManager>(this);
             IoCManager.RegisterInstance<IWebViewManagerInternal>(this);
 
@@ -49,6 +54,20 @@ namespace Robust.Client.WebView
             return _impl!.CreateBrowserWindow(createParams);
         }
 
+        public void SetResourceMimeType(string extension, string mimeType)
+        {
+            DebugTools.Assert(_impl != null, "WebViewManager has not yet been initialized!");
+
+            _impl!.SetResourceMimeType(extension, mimeType);
+        }
+
+        public bool TryGetResourceMimeType(string extension, [NotNullWhen(true)] out string? mimeType)
+        {
+            DebugTools.Assert(_impl != null, "WebViewManager has not yet been initialized!");
+
+            return _impl!.TryGetResourceMimeType(extension, out mimeType);
+        }
+
         public IWebViewControlImpl MakeControlImpl(WebViewControl owner)
         {
             DebugTools.Assert(_impl != null, "WebViewManager has not yet been initialized!");

Robust.Client/Animations/AnimationTrackControlProperty.cs

@@ -3,7 +3,7 @@ using Robust.Shared.Animations;
 
 namespace Robust.Client.Animations
 {
-    public class AnimationTrackControlProperty : AnimationTrackProperty
+    public sealed class AnimationTrackControlProperty : AnimationTrackProperty
     {
         public string? Property { get; set; }
 

Robust.Client/Animations/AnimationTrackPlaySound.cs

@@ -37,7 +37,7 @@ namespace Robust.Client.Animations
 
                 var keyFrame = KeyFrames[keyFrameIndex];
 
-                SoundSystem.Play(Filter.Local(), keyFrame.Resource, entity, keyFrame.AudioParamsFunc.Invoke());
+                SoundSystem.Play(keyFrame.Resource, Filter.Local(), entity, keyFrame.AudioParamsFunc.Invoke());
             }
 
             return (keyFrameIndex, playingTime);

Robust.Client/Animations/AnimationTrackProperty.cs

@@ -1,4 +1,4 @@
-using System;
+using System;
 using System.Collections.Generic;
 using Robust.Shared.Animations;
 using Robust.Shared.Maths;
@@ -101,7 +101,7 @@ namespace Robust.Client.Animations
                 case double d:
                     return MathHelper.Lerp(d, (double) b, t);
                 case Angle angle:
-                    return (Angle) MathHelper.Lerp(angle, (Angle) b, t);
+                    return Angle.Lerp(angle, (Angle) b, t);
                 case Color color:
                     return Color.InterpolateBetween(color, (Color) b, t);
                 case int i:

Robust.Client/Audio/Midi/Commands/MidiPanicCommand.cs

@@ -0,0 +1,22 @@
+using Robust.Shared.Console;
+using Robust.Shared.IoC;
+using Robust.Shared.Localization;
+
+namespace Robust.Client.Audio.Midi.Commands;
+
+public sealed class MidiPanicCommand : IConsoleCommand
+{
+    [Dependency] private readonly IMidiManager _midiManager = default!;
+
+    public string Command => "midipanic";
+    public string Description => Loc.GetString("midi-panic-command-description");
+    public string Help => $"{Command}";
+
+    public void Execute(IConsoleShell shell, string argStr, string[] args)
+    {
+        foreach (var renderer in _midiManager.Renderers)
+        {
+            renderer.StopAllNotes();
+        }
+    }
+}

Robust.Client/Audio/Midi/IMidiManager.cs

@@ -0,0 +1,62 @@
+using System.Collections.Generic;
+using NFluidsynth;
+using Robust.Shared.Audio.Midi;
+
+namespace Robust.Client.Audio.Midi;
+
+public interface IMidiManager
+{
+    /// <summary>
+    ///     A read-only list of all existing MIDI Renderers.
+    /// </summary>
+    IReadOnlyList<IMidiRenderer> Renderers { get; }
+
+    /// <summary>
+    ///     If true, MIDI support is available.
+    /// </summary>
+    bool IsAvailable { get; }
+
+    /// <summary>
+    ///     Volume, in db.
+    /// </summary>
+    float Volume { get; set; }
+
+    public int OcclusionCollisionMask { get; set; }
+
+    /// <summary>
+    ///     This method tries to return a midi renderer ready to be used.
+    ///     You only need to set the <see cref="IMidiRenderer.MidiProgram"/> afterwards.
+    /// </summary>
+    /// <remarks>
+    ///     This method can fail if MIDI support is not available.
+    /// </remarks>
+    /// <returns>
+    ///     <c>null</c> if MIDI support is not available.
+    /// </returns>
+    IMidiRenderer? GetNewRenderer(bool mono = true);
+
+    /// <summary>
+    ///     Creates a <see cref="RobustMidiEvent"/> given a <see cref="MidiEvent"/> and a sequencer tick.
+    /// </summary>
+    RobustMidiEvent FromFluidEvent(MidiEvent midiEvent, uint tick);
+
+    /// <summary>
+    ///     Creates a <see cref="SequencerEvent"/> given a <see cref="RobustMidiEvent"/>.
+    ///     Be sure to dispose of the result after you've used it.
+    /// </summary>
+    SequencerEvent ToSequencerEvent(RobustMidiEvent midiEvent);
+
+    /// <summary>
+    ///     Creates a <see cref="RobustMidiEvent"/> given a <see cref="SequencerEvent"/> and a sequencer tick.
+    /// </summary>
+    RobustMidiEvent FromSequencerEvent(SequencerEvent midiEvent, uint tick);
+
+    /// <summary>
+    ///     Method called every frame.
+    ///     Should be used to update positional audio.
+    /// </summary>
+    /// <param name="frameTime"></param>
+    void FrameUpdate(float frameTime);
+
+    void Shutdown();
+}

Robust.Client/Audio/Midi/IMidiRenderer.cs

@@ -0,0 +1,181 @@
+using System;
+using Robust.Client.Graphics;
+using Robust.Shared.Audio.Midi;
+using Robust.Shared.GameObjects;
+using Robust.Shared.Map;
+
+namespace Robust.Client.Audio.Midi;
+
+public enum MidiRendererStatus : byte
+{
+    None,
+    Input,
+    File,
+}
+
+public interface IMidiRenderer : IDisposable
+{
+
+    /// <summary>
+    ///     The buffered audio source of this renderer.
+    /// </summary>
+    internal IClydeBufferedAudioSource Source { get; }
+
+    /// <summary>
+    ///     Whether this renderer has been disposed or not.
+    /// </summary>
+    bool Disposed { get; }
+
+    /// <summary>
+    ///     This controls whether the midi file being played will loop or not.
+    /// </summary>
+    bool LoopMidi { get; set; }
+
+    /// <summary>
+    ///     This increases all note on velocities to 127.
+    /// </summary>
+    bool VolumeBoost { get; set; }
+
+    /// <summary>
+    ///     The midi program (instrument) the renderer is using.
+    /// </summary>
+    byte MidiProgram { get; set; }
+
+    /// <summary>
+    ///     The instrument bank the renderer is using.
+    /// </summary>
+    byte MidiBank { get; set; }
+
+    /// <summary>
+    ///     The soundfont currently selected by the renderer.
+    /// </summary>
+    uint MidiSoundfont { get; set; }
+
+    /// <summary>
+    ///     The current status of the renderer.
+    ///     "None" if the renderer isn't playing from input or a midi file.
+    ///     "Input" if the renderer is playing from midi input.
+    ///     "File" if the renderer is playing from a midi file.
+    /// </summary>
+    MidiRendererStatus Status { get; }
+
+    /// <summary>
+    ///     Whether the sound will play in stereo or mono.
+    /// </summary>
+    bool Mono { get; set; }
+
+    /// <summary>
+    ///     Whether to drop messages on the percussion channel.
+    /// </summary>
+    bool DisablePercussionChannel { get; set; }
+
+    /// <summary>
+    /// Whether to drop messages for program change events.
+    /// </summary>
+    bool DisableProgramChangeEvent { get; set; }
+
+    /// <summary>
+    ///     Gets the total number of ticks possible for the MIDI player.
+    /// </summary>
+    int PlayerTotalTick { get; }
+
+    /// <summary>
+    ///     Gets or sets (seeks) the current tick of the MIDI player.
+    /// </summary>
+    int PlayerTick { get; set; }
+
+    /// <summary>
+    ///     Gets the current tick of the sequencer.
+    /// </summary>
+    uint SequencerTick { get; }
+
+    /// <summary>
+    ///     Gets the Time Scale of the sequencer in ticks per second. Default is 1000 for 1 tick per millisecond.
+    /// </summary>
+    double SequencerTimeScale { get; }
+
+    /// <summary>
+    ///     Start listening for midi input.
+    /// </summary>
+    bool OpenInput();
+
+    /// <summary>
+    ///     Start playing a midi file.
+    /// </summary>
+    /// <param name="buffer">Bytes of the midi file</param>
+    bool OpenMidi(ReadOnlySpan<byte> buffer);
+
+    /// <summary>
+    ///     Stops listening for midi input.
+    /// </summary>
+    bool CloseInput();
+
+    /// <summary>
+    ///     Stops playing midi files.
+    /// </summary>
+    bool CloseMidi();
+
+    /// <summary>
+    ///     Stops all notes being played currently.
+    /// </summary>
+    void StopAllNotes();
+
+    /// <summary>
+    ///     Render and play MIDI to the audio source.
+    /// </summary>
+    internal void Render();
+
+    /// <summary>
+    ///     Loads a new soundfont into the renderer.
+    /// </summary>
+    void LoadSoundfont(string filename, bool resetPresets = false);
+
+    /// <summary>
+    ///     Invoked whenever a new midi event is registered.
+    /// </summary>
+    event Action<RobustMidiEvent> OnMidiEvent;
+
+    /// <summary>
+    ///     Invoked when the midi player finishes playing a song.
+    /// </summary>
+    event Action OnMidiPlayerFinished;
+
+    /// <summary>
+    ///     The entity whose position will be used for positional audio.
+    ///     This is only used if <see cref="Mono"/> is set to True.
+    /// </summary>
+    EntityUid? TrackingEntity { get; set; }
+
+    /// <summary>
+    ///     The position that will be used for positional audio.
+    ///     This is only used if <see cref="Mono"/> is set to True
+    ///     and <see cref="TrackingEntity"/> is null.
+    /// </summary>
+    EntityCoordinates? TrackingCoordinates { get; set; }
+
+    MidiRendererState RendererState { get; }
+
+    /// <summary>
+    ///     Send a midi event for the renderer to play.
+    /// </summary>
+    /// <param name="midiEvent">The midi event to be played</param>
+    void SendMidiEvent(RobustMidiEvent midiEvent);
+
+    /// <summary>
+    ///     Schedule a MIDI event to be played at a later time.
+    /// </summary>
+    /// <param name="midiEvent">the midi event in question</param>
+    /// <param name="time"></param>
+    /// <param name="absolute"></param>
+    void ScheduleMidiEvent(RobustMidiEvent midiEvent, uint time, bool absolute);
+
+    /// <summary>
+    ///     Apply a certain state to the renderer.
+    /// </summary>
+    void ApplyState(MidiRendererState state);
+
+    /// <summary>
+    ///     Actually disposes of this renderer. Do NOT use outside the MIDI thread.
+    /// </summary>
+    internal void InternalDispose();
+}

Robust.Client/Audio/Midi/MidiManager.Conversion.cs

@@ -0,0 +1,155 @@
+using NFluidsynth;
+using Robust.Shared.Audio.Midi;
+
+namespace Robust.Client.Audio.Midi;
+
+internal sealed partial class MidiManager
+{
+    public RobustMidiEvent FromFluidEvent(MidiEvent midiEvent, uint tick)
+    {
+        var status = RobustMidiEvent.MakeStatus((byte) midiEvent.Channel, (byte) midiEvent.Type);
+
+        // Control is always the first data byte. Value is always the second data byte. Fluidsynth's API ain't great.
+        var data1 = (byte) midiEvent.Control;
+        var data2 = (byte) midiEvent.Value;
+
+        // PitchBend is handled specially.
+        if (midiEvent.Type == (int) RobustMidiCommand.PitchBend)
+        {
+            // We pack pitch into both data values.
+            var pitch = (ushort) midiEvent.Pitch;
+            data1 = (byte) pitch;
+            data2 = (byte) (pitch >> 8);
+        }
+
+        return new RobustMidiEvent(status, data1, data2, tick);
+    }
+
+    public SequencerEvent ToSequencerEvent(RobustMidiEvent midiEvent)
+    {
+        var sequencerEvent = new SequencerEvent();
+
+        switch (midiEvent.MidiCommand)
+        {
+            case RobustMidiCommand.NoteOff:
+                sequencerEvent.NoteOff(midiEvent.Channel, midiEvent.Key);
+                break;
+
+            case RobustMidiCommand.NoteOn:
+                sequencerEvent.NoteOn(midiEvent.Channel, midiEvent.Key, midiEvent.Velocity);
+                break;
+
+            case RobustMidiCommand.AfterTouch:
+                sequencerEvent.KeyPressure(midiEvent.Channel, midiEvent.Key, midiEvent.Value);
+                break;
+
+            case RobustMidiCommand.ControlChange:
+                sequencerEvent.ControlChange(midiEvent.Channel, midiEvent.Control, midiEvent.Value);
+                break;
+
+            case RobustMidiCommand.ProgramChange:
+                sequencerEvent.ProgramChange(midiEvent.Channel, midiEvent.Program);
+                break;
+
+            case RobustMidiCommand.ChannelPressure:
+                sequencerEvent.ChannelPressure(midiEvent.Channel, midiEvent.Value);
+                break;
+
+            case RobustMidiCommand.PitchBend:
+                sequencerEvent.PitchBend(midiEvent.Channel, midiEvent.Pitch);
+                break;
+
+            case RobustMidiCommand.SystemMessage:
+                switch (midiEvent.Control)
+                {
+                    case 0x0 when midiEvent.Status == 0xFF:
+                        sequencerEvent.SystemReset();
+                        break;
+
+                    case 0x0B:
+                        sequencerEvent.AllNotesOff(midiEvent.Channel);
+                        break;
+
+                    default:
+                        _midiSawmill.Warning($"Tried to convert unsupported event to sequencer event:\n{midiEvent}");
+                        break;
+                }
+
+                break;
+
+            default:
+                _midiSawmill.Warning($"Tried to convert unsupported event to sequencer event:\n{midiEvent}");
+                break;
+        }
+
+        return sequencerEvent;
+    }
+
+    public RobustMidiEvent FromSequencerEvent(SequencerEvent midiEvent, uint tick)
+    {
+        byte channel = (byte) midiEvent.Channel;
+        RobustMidiCommand command = 0x0;
+        byte data1 = 0;
+        byte data2 = 0;
+
+        switch (midiEvent.Type)
+        {
+            case FluidSequencerEventType.NoteOn:
+                command = RobustMidiCommand.NoteOn;
+                data1 = (byte) midiEvent.Key;
+                data2 = (byte) midiEvent.Velocity;
+                break;
+
+            case FluidSequencerEventType.NoteOff:
+                command = RobustMidiCommand.NoteOff;
+                data1 = (byte) midiEvent.Key;
+                break;
+
+            case FluidSequencerEventType.PitchBend:
+                command = RobustMidiCommand.PitchBend;
+                // We pack pitch into both data values
+                var pitch = (ushort) midiEvent.Pitch;
+                data1 = (byte) pitch;
+                data2 = (byte) (pitch >> 8);
+                break;
+
+            case FluidSequencerEventType.ProgramChange:
+                command = RobustMidiCommand.ProgramChange;
+                data1 = (byte) midiEvent.Program;
+                break;
+
+            case FluidSequencerEventType.KeyPressure:
+                command = RobustMidiCommand.AfterTouch;
+                data1 = (byte) midiEvent.Key;
+                data2 = (byte) midiEvent.Value;
+                break;
+
+            case FluidSequencerEventType.ControlChange:
+                command = RobustMidiCommand.ControlChange;
+                data1 = (byte) midiEvent.Control;
+                data2 = (byte) midiEvent.Value;
+                break;
+
+            case FluidSequencerEventType.ChannelPressure:
+                command = RobustMidiCommand.ChannelPressure;
+                data1 = (byte) midiEvent.Value;
+                break;
+
+            case FluidSequencerEventType.AllNotesOff:
+                command = RobustMidiCommand.SystemMessage;
+                data1 = 0x0B;
+                break;
+
+            case FluidSequencerEventType.SystemReset:
+                command = RobustMidiCommand.SystemMessage;
+                channel = 0x0F;
+                break;
+
+            default:
+                _midiSawmill.Error($"Unsupported Sequencer Event: {tick:D8}: {SequencerEventToString(midiEvent)}");
+                break;
+        }
+
+        return new RobustMidiEvent(RobustMidiEvent.MakeStatus(channel, (byte)command), data1, data2, tick);
+    }
+}

Robust.Client/Audio/Midi/MidiManager.cs

@@ -7,6 +7,7 @@ using NFluidsynth;
 using Robust.Client.Graphics;
 using Robust.Client.ResourceManagement;
 using Robust.Shared;
+using Robust.Shared.Asynchronous;
 using Robust.Shared.Configuration;
 using Robust.Shared.ContentPack;
 using Robust.Shared.GameObjects;
@@ -15,269 +16,279 @@ using Robust.Shared.Log;
 using Robust.Shared.Map;
 using Robust.Shared.Maths;
 using Robust.Shared.Physics;
-using Robust.Shared.Physics.Broadphase;
 using Robust.Shared.Utility;
 using Robust.Shared.ViewVariables;
-using Logger = Robust.Shared.Log.Logger;
 
-namespace Robust.Client.Audio.Midi
+namespace Robust.Client.Audio.Midi;
+
+internal sealed partial class MidiManager : IMidiManager
 {
-    public interface IMidiManager
+    [Dependency] private readonly IEyeManager _eyeManager = default!;
+    [Dependency] private readonly IResourceManagerInternal _resourceManager = default!;
+    [Dependency] private readonly IEntityManager _entityManager = default!;
+    [Dependency] private readonly IConfigurationManager _cfgMan = default!;
+    [Dependency] private readonly IClydeAudio _clydeAudio = default!;
+    [Dependency] private readonly ITaskManager _taskManager = default!;
+    [Dependency] private readonly ILogManager _logger = default!;
+
+    private SharedPhysicsSystem _broadPhaseSystem = default!;
+
+    public IReadOnlyList<IMidiRenderer> Renderers
     {
-        /// <summary>
-        ///     This method tries to return a midi renderer ready to be used.
-        ///     You only need to set the <see cref="IMidiRenderer.MidiProgram"/> afterwards.
-        /// </summary>
-        /// <remarks>
-        ///     This method can fail if MIDI support is not available.
-        /// </remarks>
-        /// <returns>
-        ///     <c>null</c> if MIDI support is not available.
-        /// </returns>
-        IMidiRenderer? GetNewRenderer();
-
-        /// <summary>
-        ///     Method called every frame.
-        ///     Should be used to update positional audio.
-        /// </summary>
-        /// <param name="frameTime"></param>
-        void FrameUpdate(float frameTime);
-
-        /// <summary>
-        ///     Volume, in db.
-        /// </summary>
-        float Volume { get; set; }
-
-        /// <summary>
-        ///     If true, MIDI support is available.
-        /// </summary>
-        bool IsAvailable { get; }
-
-        public int OcclusionCollisionMask { get; set; }
-
-        void Shutdown();
+        get
+        {
+            lock (_renderers)
+            {
+                // Perform a copy. Sadly, we can't return a reference to the original list due to threading concerns.
+                return _renderers.ToArray();
+            }
+        }
     }
 
-    internal class MidiManager : IMidiManager
+    [ViewVariables]
+    public bool IsAvailable
     {
-        [Dependency] private readonly IEyeManager _eyeManager = default!;
-        [Dependency] private readonly IResourceManagerInternal _resourceManager = default!;
-        [Dependency] private readonly IEntityManager _entityManager = default!;
-        [Dependency] private readonly IConfigurationManager _cfgMan = default!;
-
-        private SharedPhysicsSystem _broadPhaseSystem = default!;
-
-        [ViewVariables]
-        public bool IsAvailable
+        get
         {
-            get
-            {
-                InitializeFluidsynth();
+            InitializeFluidsynth();
 
-                return FluidsynthInitialized;
-            }
+            return FluidsynthInitialized;
+        }
+    }
+
+    [ViewVariables]
+    private readonly List<IMidiRenderer> _renderers = new();
+
+    private bool _alive = true;
+    private Settings? _settings;
+    private Thread? _midiThread;
+    private ISawmill _midiSawmill = default!;
+    private float _volume = 0f;
+    private bool _volumeDirty = true;
+
+    // Not reliable until Fluidsynth is initialized!
+    [ViewVariables(VVAccess.ReadWrite)]
+    public float Volume
+    {
+        get => _volume;
+        set
+        {
+            if (MathHelper.CloseToPercent(_volume, value))
+                return;
+
+            _cfgMan.SetCVar(CVars.MidiVolume, value);
+            _volumeDirty = true;
+        }
+    }
+
+    private static readonly string[] LinuxSoundfonts =
+    {
+        "/usr/share/soundfonts/default.sf2",
+        "/usr/share/soundfonts/default.dls",
+        "/usr/share/soundfonts/FluidR3_GM.sf2",
+        "/usr/share/soundfonts/freepats-general-midi.sf2",
+        "/usr/share/sounds/sf2/default.sf2",
+        "/usr/share/sounds/sf2/default.dls",
+        "/usr/share/sounds/sf2/FluidR3_GM.sf2",
+        "/usr/share/sounds/sf2/TimGM6mb.sf2",
+    };
+
+    private const string WindowsSoundfont = @"C:\WINDOWS\system32\drivers\gm.dls";
+
+    private const string OsxSoundfont =
+        "/System/Library/Components/CoreAudio.component/Contents/Resources/gs_instruments.dls";
+
+    private const string FallbackSoundfont = "/Midi/fallback.sf2";
+
+    private const float MaxDistanceForOcclusion = 1000;
+
+    private static ResourcePath CustomSoundfontDirectory = new ResourcePath("/soundfonts/");
+
+    private readonly ResourceLoaderCallbacks _soundfontLoaderCallbacks = new();
+
+    private bool FluidsynthInitialized;
+    private bool _failedInitialize;
+
+    private NFluidsynth.Logger.LoggerDelegate _loggerDelegate = default!;
+    private ISawmill _sawmill = default!;
+
+    [ViewVariables(VVAccess.ReadWrite)]
+    public int OcclusionCollisionMask { get; set; }
+
+    private void InitializeFluidsynth()
+    {
+        if (FluidsynthInitialized || _failedInitialize) return;
+
+        _volume = _cfgMan.GetCVar(CVars.MidiVolume);
+        _cfgMan.OnValueChanged(CVars.MidiVolume, value =>
+        {
+            _volume = value;
+            _volumeDirty = true;
+        }, true);
+
+        _midiSawmill = _logger.GetSawmill("midi");
+        _midiSawmill.Level = LogLevel.Info;
+        _sawmill = _logger.GetSawmill("midi.fluidsynth");
+        _loggerDelegate = LoggerDelegate;
+
+        if (!_resourceManager.UserData.Exists(CustomSoundfontDirectory))
+        {
+            _resourceManager.UserData.CreateDir(CustomSoundfontDirectory);
+        }
+        // not a directory, preserve the old file and create an actual directory
+        else if (!_resourceManager.UserData.IsDir(CustomSoundfontDirectory))
+        {
+            _resourceManager.UserData.Rename(CustomSoundfontDirectory, CustomSoundfontDirectory.WithName(CustomSoundfontDirectory.Filename + ".old"));
+            _resourceManager.UserData.CreateDir(CustomSoundfontDirectory);
         }
 
-        [ViewVariables]
-        private readonly List<IMidiRenderer> _renderers = new();
-
-        private bool _alive = true;
-        private Settings? _settings;
-        private Thread? _midiThread;
-        private ISawmill _midiSawmill = default!;
-        private float _volume = 0f;
-        private bool _volumeDirty = true;
-
-        // Not reliable until Fluidsynth is initialized!
-        [ViewVariables(VVAccess.ReadWrite)]
-        public float Volume
+        try
         {
-            get => _volume;
-            set
-            {
-                if (MathHelper.CloseToPercent(_volume, value))
-                    return;
+            NFluidsynth.Logger.SetLoggerMethod(_loggerDelegate); // Will cause a safe DllNotFoundException if not available.
 
-                _cfgMan.SetCVar(CVars.MidiVolume, value);
-                _volumeDirty = true;
-            }
+            _settings = new Settings();
+            _settings["synth.sample-rate"].DoubleValue = 44100;
+            _settings["player.timing-source"].StringValue = "sample";
+            _settings["synth.lock-memory"].IntValue = 0;
+            _settings["synth.threadsafe-api"].IntValue = 1;
+            _settings["synth.gain"].DoubleValue = 1.0d;
+            _settings["synth.polyphony"].IntValue = 1024;
+            _settings["synth.cpu-cores"].IntValue = 2;
+            _settings["synth.midi-channels"].IntValue = 16;
+            _settings["synth.overflow.age"].DoubleValue = 3000;
+            _settings["audio.driver"].StringValue = "file";
+            _settings["audio.periods"].IntValue = 8;
+            _settings["audio.period-size"].IntValue = 4096;
+            _settings["midi.autoconnect"].IntValue = 1;
+            _settings["player.reset-synth"].IntValue = 0;
+            _settings["synth.midi-bank-select"].StringValue = "gm";
+            //_settings["synth.verbose"].IntValue = 1; // Useful for debugging.
+        }
+        catch (Exception e)
+        {
+            _midiSawmill.Warning(
+                "Failed to initialize fluidsynth due to exception, disabling MIDI support:\n{0}", e);
+            _failedInitialize = true;
+            return;
         }
 
-        private static readonly string[] LinuxSoundfonts =
-        {
-            "/usr/share/soundfonts/default.sf2",
-            "/usr/share/soundfonts/FluidR3_GM.sf2",
-            "/usr/share/soundfonts/freepats-general-midi.sf2",
-            "/usr/share/sounds/sf2/default.sf2",
-            "/usr/share/sounds/sf2/FluidR3_GM.sf2",
-            "/usr/share/sounds/sf2/TimGM6mb.sf2",
+        _midiThread = new Thread(ThreadUpdate);
+        _midiThread.Start();
+
+        _broadPhaseSystem = EntitySystem.Get<SharedPhysicsSystem>();
+        FluidsynthInitialized = true;
+    }
+
+    private void LoggerDelegate(NFluidsynth.Logger.LogLevel level, string message, IntPtr data)
+    {
+        var rLevel = level switch {
+            NFluidsynth.Logger.LogLevel.Panic => LogLevel.Error,
+            NFluidsynth.Logger.LogLevel.Error => LogLevel.Error,
+            NFluidsynth.Logger.LogLevel.Warning => LogLevel.Warning,
+            NFluidsynth.Logger.LogLevel.Information => LogLevel.Info,
+            NFluidsynth.Logger.LogLevel.Debug => LogLevel.Debug,
+            _ => LogLevel.Debug
         };
+        _sawmill.Log(rLevel, message);
+    }
 
-        private const string WindowsSoundfont = @"C:\WINDOWS\system32\drivers\gm.dls";
-
-        private const string OsxSoundfont =
-            "/System/Library/Components/CoreAudio.component/Contents/Resources/gs_instruments.dls";
-
-        private const string FallbackSoundfont = "/Midi/fallback.sf2";
-
-        private readonly ResourceLoaderCallbacks _soundfontLoaderCallbacks = new();
-
-        private bool FluidsynthInitialized;
-        private bool _failedInitialize;
-
-        private NFluidsynth.Logger.LoggerDelegate _loggerDelegate = default!;
-        private ISawmill _sawmill = default!;
-
-        [ViewVariables(VVAccess.ReadWrite)]
-        public int OcclusionCollisionMask { get; set; }
-
-        private void InitializeFluidsynth()
+    public IMidiRenderer? GetNewRenderer(bool mono = true)
+    {
+        if (!FluidsynthInitialized)
         {
-            if (FluidsynthInitialized || _failedInitialize) return;
+            InitializeFluidsynth();
 
-            _volume = _cfgMan.GetCVar(CVars.MidiVolume);
-            _cfgMan.OnValueChanged(CVars.MidiVolume, value =>
+            if (!FluidsynthInitialized) // init failed
             {
-                _volume = value;
-                _volumeDirty = true;
-            }, true);
-
-            _midiSawmill = Logger.GetSawmill("midi");
-            _sawmill = Logger.GetSawmill("midi.fluidsynth");
-            _loggerDelegate = LoggerDelegate;
-
-            try
-            {
-                NFluidsynth.Logger.SetLoggerMethod(_loggerDelegate); // Will cause a safe DllNotFoundException if not available.
-
-                _settings = new Settings();
-                _settings["synth.sample-rate"].DoubleValue = 44100;
-                _settings["player.timing-source"].StringValue = "sample";
-                _settings["synth.lock-memory"].IntValue = 0;
-                _settings["synth.threadsafe-api"].IntValue = 1;
-                _settings["synth.gain"].DoubleValue = 1.0d;
-                _settings["synth.polyphony"].IntValue = 1024;
-                _settings["synth.cpu-cores"].IntValue = 2;
-                _settings["synth.overflow.age"].DoubleValue = 3000;
-                _settings["audio.driver"].StringValue = "file";
-                _settings["audio.periods"].IntValue = 8;
-                _settings["audio.period-size"].IntValue = 4096;
-                _settings["midi.autoconnect"].IntValue = 1;
-                _settings["player.reset-synth"].IntValue = 0;
-                _settings["synth.midi-bank-select"].StringValue = "gm";
+                return null;
             }
-            catch (Exception e)
-            {
-                Logger.WarningS("midi",
-                    "Failed to initialize fluidsynth due to exception, disabling MIDI support:\n{0}", e);
-                _failedInitialize = true;
-                return;
-            }
-
-            _midiThread = new Thread(ThreadUpdate);
-            _midiThread.Start();
-
-            _broadPhaseSystem = EntitySystem.Get<SharedPhysicsSystem>();
-            FluidsynthInitialized = true;
         }
 
-        private void LoggerDelegate(NFluidsynth.Logger.LogLevel level, string message, IntPtr data)
+        var soundfontLoader = SoundFontLoader.NewDefaultSoundFontLoader(_settings);
+
+        // Just making double sure these don't get GC'd.
+        // They shouldn't, MidiRenderer keeps a ref, but making sure...
+        var handle = GCHandle.Alloc(soundfontLoader);
+
+        try
         {
-            var rLevel = level switch {
-                NFluidsynth.Logger.LogLevel.Panic => LogLevel.Error,
-                NFluidsynth.Logger.LogLevel.Error => LogLevel.Error,
-                NFluidsynth.Logger.LogLevel.Warning => LogLevel.Warning,
-                NFluidsynth.Logger.LogLevel.Information => LogLevel.Info,
-                NFluidsynth.Logger.LogLevel.Debug => LogLevel.Debug,
-                _ => LogLevel.Debug
-            };
-            _sawmill.Log(rLevel, message);
-        }
+            soundfontLoader.SetCallbacks(_soundfontLoaderCallbacks);
 
-        public IMidiRenderer? GetNewRenderer()
-        {
-            if (!FluidsynthInitialized)
+            var renderer = new MidiRenderer(_settings!, soundfontLoader, mono, this, _clydeAudio, _taskManager, _midiSawmill);
+
+            // Since the last loaded soundfont takes priority, we load the fallback soundfont before the soundfont.
+            renderer.LoadSoundfont(FallbackSoundfont);
+
+            if (OperatingSystem.IsLinux())
             {
-                InitializeFluidsynth();
-
-                if (!FluidsynthInitialized) // init failed
+                foreach (var filepath in LinuxSoundfonts)
                 {
-                    return null;
-                }
-            }
+                    if (!File.Exists(filepath) || !SoundFont.IsSoundFont(filepath)) continue;
 
-            var soundfontLoader = SoundFontLoader.NewDefaultSoundFontLoader(_settings);
-
-            // Just making double sure these don't get GC'd.
-            // They shouldn't, MidiRenderer keeps a ref, but making sure...
-            var handle = GCHandle.Alloc(soundfontLoader);
-
-            try
-            {
-                soundfontLoader.SetCallbacks(_soundfontLoaderCallbacks);
-
-                var renderer = new MidiRenderer(_settings!, soundfontLoader);
-
-                foreach (var file in _resourceManager.ContentFindFiles(("/Audio/MidiCustom/")))
-                {
-                    if (file.Extension != "sf2" && file.Extension != "dls") continue;
-                    renderer.LoadSoundfont(file.ToString());
-                }
-
-                // Since the last loaded soundfont takes priority, we load the fallback soundfont before the soundfont.
-                renderer.LoadSoundfont(FallbackSoundfont);
-
-                if (OperatingSystem.IsLinux())
-                {
-                    foreach (var filepath in LinuxSoundfonts)
+                    try
                     {
-                        if (!File.Exists(filepath) || !SoundFont.IsSoundFont(filepath)) continue;
-
-                        try
-                        {
-                            renderer.LoadSoundfont(filepath, true);
-                        }
-                        catch (Exception)
-                        {
-                            continue;
-                        }
-
-                        break;
+                        renderer.LoadSoundfont(filepath, true);
+                    }
+                    catch (Exception)
+                    {
+                        continue;
                     }
-                }
-                else if (OperatingSystem.IsMacOS())
-                {
-                    if (File.Exists(OsxSoundfont) && SoundFont.IsSoundFont(OsxSoundfont))
-                        renderer.LoadSoundfont(OsxSoundfont, true);
-                }
-                else if (OperatingSystem.IsWindows())
-                {
-                    if (File.Exists(WindowsSoundfont) && SoundFont.IsSoundFont(WindowsSoundfont))
-                        renderer.LoadSoundfont(WindowsSoundfont, true);
-                }
 
-                renderer.Source.SetVolume(Volume);
-
-                lock (_renderers)
-                {
-                    _renderers.Add(renderer);
+                    break;
                 }
-                return renderer;
             }
-            finally
+            else if (OperatingSystem.IsMacOS())
             {
-                handle.Free();
+                if (File.Exists(OsxSoundfont) && SoundFont.IsSoundFont(OsxSoundfont))
+                    renderer.LoadSoundfont(OsxSoundfont, true);
             }
+            else if (OperatingSystem.IsWindows())
+            {
+                if (File.Exists(WindowsSoundfont) && SoundFont.IsSoundFont(WindowsSoundfont))
+                    renderer.LoadSoundfont(WindowsSoundfont, true);
+            }
+
+            // Load content-specific custom soundfonts, which could override the system/fallback soundfont.
+            foreach (var file in _resourceManager.ContentFindFiles(("/Audio/MidiCustom/")))
+            {
+                if (file.Extension != "sf2" && file.Extension != "dls") continue;
+                renderer.LoadSoundfont(file.ToString());
+            }
+
+            // Load every soundfont from the user data directory last, since those may override any other soundfont.
+            _midiSawmill.Debug($"loading soundfonts from {CustomSoundfontDirectory.ToRelativePath().ToString()}/*");
+            var enumerator = _resourceManager.UserData.Find($"{CustomSoundfontDirectory.ToRelativePath().ToString()}/*").Item1;
+            foreach (var soundfont in enumerator)
+            {
+                if (soundfont.Extension != "sf2" && soundfont.Extension != "dls") continue;
+                _midiSawmill.Debug($"loading soundfont {soundfont}");
+                renderer.LoadSoundfont(soundfont.ToString());
+            }
+
+            renderer.Source.SetVolume(Volume);
+
+            lock (_renderers)
+            {
+                _renderers.Add(renderer);
+            }
+            return renderer;
+        }
+        finally
+        {
+            handle.Free();
+        }
+    }
+
+    public void FrameUpdate(float frameTime)
+    {
+        if (!FluidsynthInitialized)
+        {
+            return;
         }
 
-        public void FrameUpdate(float frameTime)
+        // Update positions of streams every frame.
+        lock (_renderers)
         {
-            if (!FluidsynthInitialized)
-            {
-                return;
-            }
-
-            // Update positions of streams every frame.
             foreach (var renderer in _renderers)
             {
                 if (renderer.Disposed)
@@ -293,136 +304,155 @@ namespace Robust.Client.Audio.Midi
                 }
 
                 MapCoordinates? mapPos = null;
+                var trackingEntity = renderer.TrackingEntity != null && !_entityManager.Deleted(renderer.TrackingEntity);
+                if (trackingEntity)
+                {
+                    renderer.TrackingCoordinates = _entityManager.GetComponent<TransformComponent>(renderer.TrackingEntity!.Value).Coordinates;
+                }
+
                 if (renderer.TrackingCoordinates != null)
                 {
                     mapPos = renderer.TrackingCoordinates.Value.ToMap(_entityManager);
                 }
-                else if (renderer.TrackingEntity != null)
-                {
-                    mapPos = _entityManager.GetComponent<TransformComponent>(renderer.TrackingEntity.Value).MapPosition;
-                }
 
-                if (mapPos != null)
+                if (mapPos != null && mapPos.Value.MapId == _eyeManager.CurrentMap)
                 {
                     var pos = mapPos.Value;
-                    if (pos.MapId != _eyeManager.CurrentMap)
-                    {
-                        renderer.Source.SetVolume(-10000000);
-                    }
-                    else
-                    {
-                        var sourceRelative = _eyeManager.CurrentEye.Position.Position - pos.Position;
-                        var occlusion = 0f;
-                        if (sourceRelative.Length > 0)
-                        {
-                            occlusion = _broadPhaseSystem.IntersectRayPenetration(
-                                pos.MapId,
-                                new CollisionRay(
-                                    pos.Position,
-                                    sourceRelative.Normalized,
-                                    OcclusionCollisionMask),
-                                sourceRelative.Length,
-                                renderer.TrackingEntity);
-                        }
 
-                        renderer.Source.SetOcclusion(occlusion);
+                    var sourceRelative = _eyeManager.CurrentEye.Position.Position - pos.Position;
+                    var occlusion = 0f;
+                    if (sourceRelative.Length > 0)
+                    {
+                        occlusion = _broadPhaseSystem.IntersectRayPenetration(
+                            pos.MapId,
+                            new CollisionRay(
+                                pos.Position,
+                                sourceRelative.Normalized,
+                                OcclusionCollisionMask),
+                            MathF.Min(sourceRelative.Length, MaxDistanceForOcclusion),
+                            renderer.TrackingEntity);
                     }
 
-                    if (renderer.Source.SetPosition(pos.Position))
+                    renderer.Source.SetOcclusion(occlusion);
+
+                    if (!renderer.Source.SetPosition(pos.Position))
                     {
-                        continue;
+                        return;
                     }
 
-                    if (renderer.TrackingEntity != null)
+                    if (trackingEntity)
                     {
-                        renderer.Source.SetVelocity(renderer.TrackingEntity.Value.GlobalLinearVelocity());
+                        renderer.Source.SetVelocity(renderer.TrackingEntity!.Value.GlobalLinearVelocity());
                     }
-
-                    if (float.IsNaN(pos.Position.X) || float.IsNaN(pos.Position.Y))
-                    {
-                        // just duck out instead of move to NaN
-                        renderer.Source.SetOcclusion(float.MaxValue);
-                        continue;
-                    }
-
-                    _midiSawmill?.Warning("Interrupting positional audio, can't set position.");
-                    renderer.Source.StopPlaying();
                 }
-            }
-
-            _volumeDirty = false;
-        }
-
-        /// <summary>
-        ///     Main method for the thread rendering the midi audio.
-        /// </summary>
-        private void ThreadUpdate()
-        {
-            while (_alive)
-            {
-                lock (_renderers)
+                else
                 {
-                    for (var i = 0; i < _renderers.Count; i++)
-                    {
-                        var renderer = _renderers[i];
-                        if (!renderer.Disposed)
-                            renderer.Render();
-                        else
-                        {
-                            renderer.InternalDispose();
-                            _renderers.Remove(renderer);
-                        }
-                    }
+                    renderer.Source.SetOcclusion(float.MaxValue);
                 }
-
-                Thread.Sleep(1);
             }
         }
 
-        public void Shutdown()
-        {
-            _alive = false;
-            _midiThread?.Join();
-            _settings?.Dispose();
+        _volumeDirty = false;
+    }
 
+    /// <summary>
+    ///     Main method for the thread rendering the midi audio.
+    /// </summary>
+    private void ThreadUpdate()
+    {
+        while (_alive)
+        {
             lock (_renderers)
             {
-                foreach (var renderer in _renderers)
+                for (var i = 0; i < _renderers.Count; i++)
                 {
-                    renderer?.Dispose();
+                    var renderer = _renderers[i];
+                    if (!renderer.Disposed)
+                        renderer.Render();
+                    else
+                    {
+                        renderer.InternalDispose();
+                        _renderers.Remove(renderer);
+                    }
                 }
             }
 
-            if (FluidsynthInitialized && !_failedInitialize)
+            Thread.Sleep(1);
+        }
+    }
+
+    public void Shutdown()
+    {
+        _alive = false;
+        _midiThread?.Join();
+        _settings?.Dispose();
+
+        lock (_renderers)
+        {
+            foreach (var renderer in _renderers)
             {
-                NFluidsynth.Logger.SetLoggerMethod(null);
+                renderer?.Dispose();
             }
         }
 
-        /// <summary>
-        ///     This class is used to load soundfonts.
-        /// </summary>
-        private class ResourceLoaderCallbacks : SoundFontLoaderCallbacks
+        if (FluidsynthInitialized && !_failedInitialize)
         {
-            private readonly Dictionary<int, Stream> _openStreams = new();
-            private int _nextStreamId = 1;
+            NFluidsynth.Logger.SetLoggerMethod(null);
+        }
+    }
 
-            public override IntPtr Open(string filename)
+    /// <summary>
+    ///     Internal method to get a human-readable representation of a <see cref="SequencerEvent"/>.
+    /// </summary>
+    internal static string SequencerEventToString(SequencerEvent midiEvent)
+    {
+        // ReSharper disable once UseStringInterpolation
+        return string.Format(
+            "{0} chan:{1:D2} key:{2:D5} bank:{3:D2} ctrl:{4:D5} dur:{5:D5} pitch:{6:D5} prog:{7:D3} val:{8:D5} vel:{9:D5}",
+            midiEvent.Type.ToString().PadLeft(22),
+            midiEvent.Channel,
+            midiEvent.Key,
+            midiEvent.Bank,
+            midiEvent.Control,
+            midiEvent.Duration,
+            midiEvent.Pitch,
+            midiEvent.Program,
+            midiEvent.Value,
+            midiEvent.Velocity);
+    }
+
+    /// <summary>
+    ///     This class is used to load soundfonts.
+    /// </summary>
+    private sealed class ResourceLoaderCallbacks : SoundFontLoaderCallbacks
+    {
+        private readonly Dictionary<int, Stream> _openStreams = new();
+        private int _nextStreamId = 1;
+
+        public override IntPtr Open(string filename)
+        {
+            if (string.IsNullOrEmpty(filename))
             {
-                if (string.IsNullOrEmpty(filename))
-                {
-                    return IntPtr.Zero;
-                }
+                return IntPtr.Zero;
+            }
 
-                Stream? stream;
-                var resourceCache = IoCManager.Resolve<IResourceCache>();
-                var resourcePath = new ResourcePath(filename);
+            Stream? stream;
+            var resourceCache = IoCManager.Resolve<IResourceCache>();
+            var resourcePath = new ResourcePath(filename);
 
-                if (resourcePath.IsRooted && resourceCache.ContentFileExists(filename))
+            if (resourcePath.IsRooted)
+            {
+                // is it in content?
+                if (resourceCache.ContentFileExists(filename))
                 {
                     if (!resourceCache.TryContentFileRead(filename, out stream))
                         return IntPtr.Zero;
                 }
+                // is it in userdata?
+                else if (resourceCache.UserData.Exists(resourcePath))
+                {
+                    stream = resourceCache.UserData.OpenRead(resourcePath);
+                }
                 else if (File.Exists(filename))
                 {
                     stream = File.OpenRead(filename);
@@ -431,73 +461,81 @@ namespace Robust.Client.Audio.Midi
                 {
                     return IntPtr.Zero;
                 }
-
-                var id = _nextStreamId++;
-
-                _openStreams.Add(id, stream);
-
-                return (IntPtr) id;
+            }
+            else if (File.Exists(filename))
+            {
+                stream = File.OpenRead(filename);
+            }
+            else
+            {
+                return IntPtr.Zero;
             }
 
-            public override unsafe int Read(IntPtr buf, long count, IntPtr sfHandle)
-            {
-                var length = (int) count;
-                var span = new Span<byte>(buf.ToPointer(), length);
-                var stream = _openStreams[(int) sfHandle];
+            var id = _nextStreamId++;
 
-                // Fluidsynth's docs state that this method should leave the buffer unmodified if it fails. (returns -1)
-                try
+            _openStreams.Add(id, stream);
+
+            return (IntPtr) id;
+        }
+
+        public override unsafe int Read(IntPtr buf, long count, IntPtr sfHandle)
+        {
+            var length = (int) count;
+            var span = new Span<byte>(buf.ToPointer(), length);
+            var stream = _openStreams[(int) sfHandle];
+
+            // Fluidsynth's docs state that this method should leave the buffer unmodified if it fails. (returns -1)
+            try
+            {
+                // Fluidsynth does a LOT of tiny allocations (frankly, way too much).
+                if (count < 1024)
                 {
-                    // Fluidsynth does a LOT of tiny allocations (frankly, way too much).
-                    if (count < 1024)
-                    {
-                        // ReSharper disable once SuggestVarOrType_Elsewhere
-                        Span<byte> buffer = stackalloc byte[(int)count];
+                    // ReSharper disable once SuggestVarOrType_Elsewhere
+                    Span<byte> buffer = stackalloc byte[(int)count];
 
-                        stream.ReadExact(buffer);
+                    stream.ReadExact(buffer);
 
-                        buffer.CopyTo(span);
-                    }
-                    else
-                    {
-                        var buffer = stream.ReadExact(length);
-
-                        buffer.CopyTo(span);
-                    }
+                    buffer.CopyTo(span);
                 }
-                catch (EndOfStreamException)
+                else
                 {
-                    return -1;
+                    var buffer = stream.ReadExact(length);
+
+                    buffer.CopyTo(span);
                 }
-
-                return 0;
             }
-
-            public override int Seek(IntPtr sfHandle, int offset, SeekOrigin origin)
+            catch (EndOfStreamException)
             {
-                var stream = _openStreams[(int) sfHandle];
-
-                stream.Seek(offset, origin);
-
-                return 0;
+                return -1;
             }
 
-            public override int Tell(IntPtr sfHandle)
-            {
-                var stream = _openStreams[(int) sfHandle];
+            return 0;
+        }
 
-                return (int) stream.Position;
-            }
+        public override int Seek(IntPtr sfHandle, int offset, SeekOrigin origin)
+        {
+            var stream = _openStreams[(int) sfHandle];
 
-            public override int Close(IntPtr sfHandle)
-            {
-                if (!_openStreams.Remove((int) sfHandle, out var stream))
-                    return -1;
+            stream.Seek(offset, origin);
 
-                stream.Dispose();
-                return 0;
+            return 0;
+        }
+
+        public override int Tell(IntPtr sfHandle)
+        {
+            var stream = _openStreams[(int) sfHandle];
+
+            return (int) stream.Position;
+        }
+
+        public override int Close(IntPtr sfHandle)
+        {
+            if (!_openStreams.Remove((int) sfHandle, out var stream))
+                return -1;
+
+            stream.Dispose();
+            return 0;
 
-            }
         }
     }
 }

Robust.Client/Audio/Midi/MidiRendererState.cs

@@ -0,0 +1,80 @@
+using System;
+using System.Runtime.InteropServices;
+using Robust.Shared.Utility;
+
+namespace Robust.Client.Audio.Midi;
+
+public struct MidiRendererState
+{
+    internal FixedArray16<FixedArray128<byte>> NoteVelocities;
+    internal FixedArray16<FixedArray128<byte>> Controllers;
+    internal FixedArray16<byte> Program;
+    internal FixedArray16<byte> ChannelPressure;
+    internal FixedArray16<ushort> PitchBend;
+
+    internal Span<byte> AsSpan => MemoryMarshal.CreateSpan(ref NoteVelocities._00._00, 4160);
+
+    static unsafe MidiRendererState()
+    {
+        var s = new MidiRendererState();
+        DebugTools.Assert(s.AsSpan.Length == sizeof(MidiRendererState),
+            $"{nameof(MidiRendererState)}'s {nameof(AsSpan)} length does not match struct size! Was: {s.AsSpan.Length} Expected: {sizeof(MidiRendererState)}");
+    }
+
+    public MidiRendererState()
+    {
+        NoteVelocities = default;
+        Program = default;
+        ChannelPressure = default;
+        PitchBend = default;
+        Controllers = default;
+
+        // PitchBend is at 8192 by default.
+        PitchBend.AsSpan.Fill(8192);
+
+        // Controller defaults
+        Controllers.AsSpan.Fill(new FixedArray128<byte>
+        {
+            // Bank selection default
+            _00 = 0,
+
+            // Volume controller default
+            _07 = 100,
+
+            // Balance controller default
+            _08 = 64,
+
+            // Pan controller default
+            _10 = 64,
+
+            // Expression controller default
+            _11 = 127,
+
+            // Controller 11 default
+            _43 = 127,
+
+            // Sound controllers 1 to 10 defaults
+            _70 = 64,
+            _71 = 64,
+            _72 = 64,
+            _73 = 64,
+            _74 = 64,
+            _75 = 64,
+            _76 = 64,
+            _77 = 64,
+            _78 = 64,
+            _79 = 64,
+
+            // Portamento default
+            _84 = 255,
+
+            // Non-Registered Parameter Number defaults
+            _98 = 127, // LSB
+            _99 = 127, // MSB
+
+            // Registered Parameter Number defaults
+            _100 = 127, // LSB
+            _101 = 127, // MSB
+        });
+    }
+}

Robust.Client/BaseClient.cs

@@ -1,4 +1,4 @@
-using System;
+using System;
 using System.Net;
 using Robust.Client.Debugging;
 using Robust.Client.GameObjects;
@@ -13,6 +13,7 @@ using Robust.Shared.IoC;
 using Robust.Shared.Log;
 using Robust.Shared.Map;
 using Robust.Shared.Network;
+using Robust.Shared.Network.Messages;
 using Robust.Shared.Players;
 using Robust.Shared.Timing;
 using Robust.Shared.Utility;
@@ -20,13 +21,12 @@ using Robust.Shared.Utility;
 namespace Robust.Client
 {
     /// <inheritdoc />
-    public class BaseClient : IBaseClient
+    public sealed class BaseClient : IBaseClient
     {
         [Dependency] private readonly IClientNetManager _net = default!;
         [Dependency] private readonly IPlayerManager _playMan = default!;
         [Dependency] private readonly INetConfigurationManager _configManager = default!;
         [Dependency] private readonly IClientEntityManager _entityManager = default!;
-        [Dependency] private readonly IEntityLookup _entityLookup = default!;
         [Dependency] private readonly IMapManager _mapManager = default!;
         [Dependency] private readonly IDiscordRichPresence _discord = default!;
         [Dependency] private readonly IGameTiming _timing = default!;
@@ -46,6 +46,8 @@ namespace Robust.Client
 
         public string? LastDisconnectReason { get; private set; }
 
+        private (TimeSpan, GameTick) _timeBase;
+
         /// <inheritdoc />
         public void Initialize()
         {
@@ -53,20 +55,34 @@ namespace Robust.Client
             _net.ConnectFailed += OnConnectFailed;
             _net.Disconnect += OnNetDisconnect;
 
+            _net.RegisterNetMessage<MsgSyncTimeBase>(
+                SyncTimeBase,
+                NetMessageAccept.Handshake | NetMessageAccept.Client);
+
             _configManager.OnValueChanged(CVars.NetTickrate, TickRateChanged, invokeImmediately: true);
 
             _playMan.Initialize();
             Reset();
         }
 
-        private void TickRateChanged(int tickrate)
+        private void SyncTimeBase(MsgSyncTimeBase message)
+        {
+            Logger.DebugS("client", $"Synchronized time base: {message.Tick}: {message.Time}");
+
+            if (RunLevel >= ClientRunLevel.Connected)
+                _timing.TimeBase = (message.Time, message.Tick);
+            else
+                _timeBase = (message.Time, message.Tick);
+        }
+
+        private void TickRateChanged(int tickrate, in CVarChangeInfo info)
         {
             if (GameInfo != null)
             {
                 GameInfo.TickRate = (byte) tickrate;
             }
 
-            _timing.TickRate = (byte) tickrate;
+            _timing.SetTickRateAt((byte) tickrate, info.TickChanged);
             Logger.InfoS("client", $"Tickrate changed to: {tickrate} on tick {_timing.CurTick}");
         }
 
@@ -75,7 +91,7 @@ namespace Robust.Client
         {
             if (RunLevel == ClientRunLevel.Connecting)
             {
-                _net.Shutdown("Client mashing that connect button.");
+                _net.Reset("Client mashing that connect button.");
                 Reset();
             }
 
@@ -203,7 +219,9 @@ namespace Robust.Client
         {
             DebugTools.Assert(RunLevel > ClientRunLevel.Initialize);
 
-            PlayerLeaveServer?.Invoke(this, new PlayerEventArgs(_playMan.LocalPlayer?.Session));
+            // Don't invoke PlayerLeaveServer if PlayerJoinedServer & GameStartedSetup hasn't been called yet.
+            if (RunLevel > ClientRunLevel.Connecting)
+                PlayerLeaveServer?.Invoke(this, new PlayerEventArgs(_playMan.LocalPlayer?.Session));
 
             LastDisconnectReason = args.Reason;
             GameStoppedReset();
@@ -213,9 +231,8 @@ namespace Robust.Client
         {
             _entityManager.Startup();
             _mapManager.Startup();
-            _entityLookup.Startup();
 
-            _timing.ResetSimTime();
+            _timing.ResetSimTime(_timeBase);
             _timing.Paused = false;
         }
 
@@ -224,7 +241,6 @@ namespace Robust.Client
             IoCManager.Resolve<INetConfigurationManager>().FlushMessages();
             _gameStates.Reset();
             _playMan.Shutdown();
-            _entityLookup.Shutdown();
             _entityManager.Shutdown();
             _mapManager.Shutdown();
             _discord.ClearPresence();
@@ -291,7 +307,7 @@ namespace Robust.Client
     /// <summary>
     ///     Event arguments for when something changed with the player.
     /// </summary>
-    public class PlayerEventArgs : EventArgs
+    public sealed class PlayerEventArgs : EventArgs
     {
         /// <summary>
         ///     The session that triggered the event.
@@ -310,7 +326,7 @@ namespace Robust.Client
     /// <summary>
     ///     Event arguments for when the RunLevel has changed in the BaseClient.
     /// </summary>
-    public class RunLevelChangedEventArgs : EventArgs
+    public sealed class RunLevelChangedEventArgs : EventArgs
     {
         /// <summary>
         ///     RunLevel that the BaseClient switched from.
@@ -335,7 +351,7 @@ namespace Robust.Client
     /// <summary>
     ///     Info about the server and player that is sent to the client while connecting.
     /// </summary>
-    public class ServerInfo
+    public sealed class ServerInfo
     {
         public ServerInfo(string serverName)
         {

Robust.Client/ClientIoC.cs

@@ -11,6 +11,7 @@ using Robust.Client.Input;
 using Robust.Client.Map;
 using Robust.Client.Placement;
 using Robust.Client.Player;
+using Robust.Client.Profiling;
 using Robust.Client.Prototypes;
 using Robust.Client.Reflection;
 using Robust.Client.ResourceManagement;
@@ -43,11 +44,10 @@ namespace Robust.Client
             IoCManager.Register<IGameTiming, ClientGameTiming>();
             IoCManager.Register<IClientGameTiming, ClientGameTiming>();
             IoCManager.Register<IPrototypeManager, ClientPrototypeManager>();
-            IoCManager.Register<IMapManager, ClientMapManager>();
-            IoCManager.Register<IMapManagerInternal, ClientMapManager>();
-            IoCManager.Register<IClientMapManager, ClientMapManager>();
+            IoCManager.Register<IMapManager, NetworkedMapManager>();
+            IoCManager.Register<IMapManagerInternal, NetworkedMapManager>();
+            IoCManager.Register<INetworkedMapManager, NetworkedMapManager>();
             IoCManager.Register<IEntityManager, ClientEntityManager>();
-            IoCManager.Register<IEntityLookup, EntityLookup>();
             IoCManager.Register<IReflectionManager, ClientReflectionManager>();
             IoCManager.Register<IConsoleHost, ClientConsoleHost>();
             IoCManager.Register<IClientConsoleHost, ClientConsoleHost>();
@@ -62,6 +62,8 @@ namespace Robust.Client
             IoCManager.Register<IResourceCache, ResourceCache>();
             IoCManager.Register<IResourceCacheInternal, ResourceCache>();
             IoCManager.Register<IClientNetManager, NetManager>();
+            IoCManager.Register<EntityManager, ClientEntityManager>();
+            IoCManager.Register<ClientEntityManager>();
             IoCManager.Register<IClientEntityManager, ClientEntityManager>();
             IoCManager.Register<IClientEntityManagerInternal, ClientEntityManager>();
             IoCManager.Register<IEntityNetworkManager, ClientEntityManager>();
@@ -72,11 +74,11 @@ namespace Robust.Client
             IoCManager.Register<IStateManager, StateManager>();
             IoCManager.Register<IUserInterfaceManager, UserInterfaceManager>();
             IoCManager.Register<IUserInterfaceManagerInternal, UserInterfaceManager>();
-            IoCManager.Register<IDebugDrawing, DebugDrawing>();
             IoCManager.Register<ILightManager, LightManager>();
             IoCManager.Register<IDiscordRichPresence, DiscordRichPresence>();
             IoCManager.Register<IMidiManager, MidiManager>();
             IoCManager.Register<IAuthManager, AuthManager>();
+            IoCManager.Register<ProfViewManager>();
             IoCManager.Register<IPhysicsManager, PhysicsManager>();
             switch (mode)
             {

Robust.Client/Console/ClientConGroupController.cs

@@ -2,7 +2,7 @@
 
 namespace Robust.Client.Console
 {
-    public class ClientConGroupController : IClientConGroupController
+    public sealed class ClientConGroupController : IClientConGroupController
     {
         private IClientConGroupImplementation? _implementation;
         public event Action? ConGroupUpdated;

Robust.Client/Console/ClientConsoleHost.Completions.cs

@@ -0,0 +1,98 @@
+using System.Collections.Generic;
+using System.Linq;
+using System.Threading;
+using System.Threading.Tasks;
+using Robust.Shared;
+using Robust.Shared.Console;
+using Robust.Shared.Network.Messages;
+
+namespace Robust.Client.Console;
+
+internal sealed partial class ClientConsoleHost
+{
+    private readonly Dictionary<int, PendingCompletion> _completionsPending = new();
+    private int _completionSeq;
+
+
+    public async Task<CompletionResult> GetCompletions(List<string> args, CancellationToken cancel)
+    {
+        // Last element is the command currently being typed. May be empty.
+
+        // Logger.Debug($"Running completions: {string.Join(", ", args)}");
+
+        var delay = _cfg.GetCVar(CVars.ConCompletionDelay);
+        if (delay > 0)
+            await Task.Delay((int)(delay * 1000), cancel);
+
+        return await CalcCompletions(args, cancel);
+    }
+
+    private Task<CompletionResult> CalcCompletions(List<string> args, CancellationToken cancel)
+    {
+        if (args.Count == 1)
+        {
+            // Typing out command name, handle this ourselves.
+            var cmdOptions = CompletionResult.FromOptions(
+                RegisteredCommands.Values
+                    .Where(c => CanExecute(c.Command))
+                    .OrderBy(c => c.Command)
+                    .Select(c => new CompletionOption(c.Command, c.Description)));
+
+            return Task.FromResult(cmdOptions);
+        }
+
+        if (!RegisteredCommands.TryGetValue(args[0], out var cmd))
+            return Task.FromResult(CompletionResult.Empty);
+
+        return cmd.GetCompletionAsync(LocalShell, args.ToArray()[1..], cancel).AsTask();
+    }
+
+    private Task<CompletionResult> DoServerCompletions(List<string> args, CancellationToken cancel)
+    {
+        var tcs = new TaskCompletionSource<CompletionResult>();
+        var cts = CancellationTokenSource.CreateLinkedTokenSource(cancel);
+        var seq = _completionSeq++;
+
+        var pending = new PendingCompletion
+        {
+            Cts = cts,
+            Tcs = tcs
+        };
+
+        var msg = new MsgConCompletion
+        {
+            Args = args.ToArray(),
+            Seq = seq
+        };
+
+        cts.Token.Register(() =>
+        {
+            tcs.SetCanceled(cts.Token);
+            cts.Dispose();
+            _completionsPending.Remove(seq);
+        }, true);
+
+        NetManager.ClientSendMessage(msg);
+
+        _completionsPending.Add(seq, pending);
+
+        return tcs.Task;
+    }
+
+    private void ProcessCompletionResp(MsgConCompletionResp message)
+    {
+        if (!_completionsPending.TryGetValue(message.Seq, out var pending))
+            return;
+
+        pending.Cts.Dispose();
+        pending.Tcs.SetResult(message.Result);
+
+        _completionsPending.Remove(message.Seq);
+    }
+
+    private struct PendingCompletion
+    {
+        public TaskCompletionSource<CompletionResult> Tcs;
+        public CancellationTokenSource Cts;
+    }
+}

Robust.Client/Console/ClientConsoleHost.cs

@@ -1,10 +1,15 @@
 using System;
 using System.Collections.Generic;
+using System.Linq;
+using System.Threading;
+using System.Threading.Tasks;
 using Robust.Client.Log;
 using Robust.Client.Player;
+using Robust.Shared.Configuration;
 using Robust.Shared.Console;
 using Robust.Shared.Enums;
 using Robust.Shared.IoC;
+using Robust.Shared.Localization;
 using Robust.Shared.Log;
 using Robust.Shared.Network;
 using Robust.Shared.Network.Messages;
@@ -14,7 +19,7 @@ using Robust.Shared.Utility;
 
 namespace Robust.Client.Console
 {
-    public class AddStringArgs : EventArgs
+    public sealed class AddStringArgs : EventArgs
     {
         public string Text { get; }
 
@@ -30,7 +35,7 @@ namespace Robust.Client.Console
         }
     }
 
-    public class AddFormattedMessageArgs : EventArgs
+    public sealed class AddFormattedMessageArgs : EventArgs
     {
         public readonly FormattedMessage Message;
 
@@ -41,18 +46,24 @@ namespace Robust.Client.Console
     }
 
     /// <inheritdoc cref="IClientConsoleHost" />
-    internal class ClientConsoleHost : ConsoleHost, IClientConsoleHost
+    internal sealed partial class ClientConsoleHost : ConsoleHost, IClientConsoleHost, IConsoleHostInternal
     {
         [Dependency] private readonly IClientConGroupController _conGroup = default!;
+        [Dependency] private readonly IConfigurationManager _cfg = default!;
+        [Dependency] private readonly IPlayerManager _player = default!;
 
         private bool _requestedCommands;
 
+        public ClientConsoleHost() : base(isServer: false) {}
+
         /// <inheritdoc />
         public void Initialize()
         {
             NetManager.RegisterNetMessage<MsgConCmdReg>(HandleConCmdReg);
             NetManager.RegisterNetMessage<MsgConCmdAck>(HandleConCmdAck);
             NetManager.RegisterNetMessage<MsgConCmd>(ProcessCommand);
+            NetManager.RegisterNetMessage<MsgConCompletion>();
+            NetManager.RegisterNetMessage<MsgConCompletionResp>(ProcessCompletionResp);
 
             _requestedCommands = false;
             NetManager.Connected += OnNetworkConnected;
@@ -88,6 +99,11 @@ namespace Robust.Client.Console
             OutputText(text, true, true);
         }
 
+        public bool IsCmdServer(IConsoleCommand cmd)
+        {
+            return cmd is ServerDummyCommand;
+        }
+
         public override event ConAnyCommandCallback? AnyCommandExecuted;
 
         /// <inheritdoc />
@@ -108,9 +124,7 @@ namespace Robust.Client.Console
 
             if (AvailableCommands.ContainsKey(commandName))
             {
-                var playerManager = IoCManager.Resolve<IPlayerManager>();
-
-                if (!_conGroup.CanCommand(commandName) && playerManager.LocalPlayer?.Session.Status > SessionStatus.Connecting)
+                if (!CanExecute(commandName))
                 {
                     WriteError(null, $"Insufficient perms for command: {commandName}");
                     return;
@@ -128,13 +142,23 @@ namespace Robust.Client.Console
                 WriteError(null, "Unknown command: " + commandName);
         }
 
+        private bool CanExecute(string cmdName)
+        {
+            // When not connected to a server, you can run all local commands.
+            // When connected to a server, you can only run commands according to the con group controller.
+
+            return _player.LocalPlayer == null
+                   || _player.LocalPlayer.Session.Status <= SessionStatus.Connecting
+                   || _conGroup.CanCommand(cmdName);
+        }
+
         /// <inheritdoc />
         public override void RemoteExecuteCommand(ICommonSession? session, string command)
         {
             if (!NetManager.IsConnected) // we don't care about session on client
                 return;
 
-            var msg = NetManager.CreateNetMessage<MsgConCmd>();
+            var msg = new MsgConCmd();
             msg.Text = command;
             NetManager.ClientSendMessage(msg);
         }
@@ -198,36 +222,69 @@ namespace Robust.Client.Console
             if (!NetManager.IsConnected)
                 return;
 
-            var msg = NetManager.CreateNetMessage<MsgConCmdReg>();
+            var msg = new MsgConCmdReg();
             NetManager.ClientSendMessage(msg);
 
             _requestedCommands = true;
         }
-    }
 
-    /// <summary>
-    /// These dummies are made purely so list and help can list server-side commands.
-    /// </summary>
-    [Reflect(false)]
-    internal class ServerDummyCommand : IConsoleCommand
-    {
-        internal ServerDummyCommand(string command, string help, string description)
+        /// <summary>
+        /// These dummies are made purely so list and help can list server-side commands.
+        /// </summary>
+        [Reflect(false)]
+        private sealed class ServerDummyCommand : IConsoleCommand
         {
-            Command = command;
-            Help = help;
-            Description = description;
+            internal ServerDummyCommand(string command, string help, string description)
+            {
+                Command = command;
+                Help = help;
+                Description = description;
+            }
+
+            public string Command { get; }
+
+            public string Description { get; }
+
+            public string Help { get; }
+
+            // Always forward to server.
+            public void Execute(IConsoleShell shell, string argStr, string[] args)
+            {
+                shell.RemoteExecuteCommand(argStr);
+            }
+
+            public async ValueTask<CompletionResult> GetCompletionAsync(
+                IConsoleShell shell,
+                string[] args,
+                CancellationToken cancel)
+            {
+                var host = (ClientConsoleHost)shell.ConsoleHost;
+                var argsList = args.ToList();
+                argsList.Insert(0, Command);
+
+                return await host.DoServerCompletions(argsList, cancel);
+            }
         }
 
-        public string Command { get; }
-
-        public string Description { get; }
-
-        public string Help { get; }
-
-        // Always forward to server.
-        public void Execute(IConsoleShell shell, string argStr, string[] args)
+        private sealed class RemoteExecCommand : IConsoleCommand
         {
-            shell.RemoteExecuteCommand(argStr);
+            public string Command => ">";
+            public string Description => Loc.GetString("cmd-remoteexec-desc");
+            public string Help => Loc.GetString("cmd-remoteexec-help");
+
+            public void Execute(IConsoleShell shell, string argStr, string[] args)
+            {
+                shell.RemoteExecuteCommand(argStr["> ".Length..]);
+            }
+
+            public async ValueTask<CompletionResult> GetCompletionAsync(
+                IConsoleShell shell,
+                string[] args,
+                CancellationToken cancel)
+            {
+                var host = (ClientConsoleHost)shell.ConsoleHost;
+                return await host.DoServerCompletions(args.ToList(), cancel);
+            }
         }
     }
 }

Robust.Client/Console/Commands/ConfigurationCommands.cs

@@ -1,5 +1,3 @@
-using System;
-using System.Linq;
 using JetBrains.Annotations;
 using Robust.Shared.Configuration;
 using Robust.Shared.Console;
@@ -8,58 +6,7 @@ using Robust.Shared.IoC;
 namespace Robust.Client.Console.Commands
 {
     [UsedImplicitly]
-    internal sealed class CVarCommand : SharedCVarCommand, IConsoleCommand
-    {
-        public override void Execute(IConsoleShell shell, string argStr, string[] args)
-        {
-            if (args.Length < 1 || args.Length > 2)
-            {
-                shell.WriteError("Must provide exactly one or two arguments.");
-                return;
-            }
-
-            var configManager = IoCManager.Resolve<IConfigurationManager>();
-            var name = args[0];
-
-            if (name == "?")
-            {
-                var cvars = configManager.GetRegisteredCVars().OrderBy(c => c);
-                shell.WriteLine(string.Join("\n", cvars));
-                return;
-            }
-
-            if (!configManager.IsCVarRegistered(name))
-            {
-                shell.WriteError($"CVar '{name}' is not registered. Use 'cvar ?' to get a list of all registered CVars.");
-                return;
-            }
-
-            if (args.Length == 1)
-            {
-                // Read CVar
-                var value = configManager.GetCVar<object>(name);
-                shell.WriteLine(value.ToString() ?? "");
-            }
-            else
-            {
-                // Write CVar
-                var value = args[1];
-                var type = configManager.GetCVarType(name);
-                try
-                {
-                    var parsed = ParseObject(type, value);
-                    configManager.SetCVar(name, parsed);
-                }
-                catch (FormatException)
-                {
-                    shell.WriteLine($"Input value is in incorrect format for type {type}");
-                }
-            }
-        }
-    }
-
-    [UsedImplicitly]
-    public class SaveConfig : IConsoleCommand
+    public sealed class SaveConfig : IConsoleCommand
     {
         public string Command => "saveconfig";
         public string Description => "Saves the client configuration to the config file";

Robust.Client/Console/Commands/ConsoleCommands.cs

@@ -6,7 +6,7 @@ using Robust.Shared.Console;
 
 namespace Robust.Client.Console.Commands
 {
-    class ClearCommand : IConsoleCommand
+    sealed class ClearCommand : IConsoleCommand
     {
         public string Command => "cls";
         public string Help => "Clears the debug console of all messages.";
@@ -18,7 +18,7 @@ namespace Robust.Client.Console.Commands
         }
     }
 
-    class FillCommand : IConsoleCommand
+    sealed class FillCommand : IConsoleCommand
     {
         public string Command => "fill";
         public string Help => "Fills the console with some nonsense for debugging.";