Version: 211.0.2

From moony my git patch didn't apply so done manually

Directory.Packages.props

@@ -51,11 +51,14 @@
     <PackageVersion Include="SpaceWizards.SharpFont" Version="1.0.2" />
     <PackageVersion Include="SpaceWizards.Sodium" Version="0.2.1" />
     <PackageVersion Include="System.Numerics.Vectors" Version="4.5.0" />
+    <PackageVersion Include="System.Memory" Version="4.5.5" />
+    <PackageVersion Include="System.Runtime.CompilerServices.Unsafe" Version="6.0.0" />
     <PackageVersion Include="TerraFX.Interop.Windows" Version="10.0.22621.5" />
     <PackageVersion Include="TerraFX.Interop.Xlib" Version="6.4.0" />
     <PackageVersion Include="VorbisPizza" Version="1.3.0" />
     <PackageVersion Include="YamlDotNet" Version="13.7.1" />
     <PackageVersion Include="prometheus-net" Version="8.2.1" />
     <PackageVersion Include="prometheus-net.DotNetRuntime" Version="4.4.0" />
+    <PackageVersion Include="PolySharp" Version="1.14.1" />
   </ItemGroup>
 </Project>

MSBuild/Robust.Engine.Version.props

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

RELEASE-NOTES.md

@@ -54,6 +54,100 @@ END TEMPLATE-->
 *None yet*
 
 
+## 211.0.2
+
+### Bugfixes
+
+* Fix TextureRect scaling not handling UIScale correctly.
+
+
+## 211.0.1
+
+### Bugfixes
+
+* Fix GridChunkEnumerator on maps.
+
+
+## 211.0.0
+
+### Breaking changes
+
+* Moved ChunkIndicesEnumerator to engine and to a re-useable namespace at Robust.Shared/Maps.
+
+### New features
+
+* Added an Enlarged method for Box2Rotated.
+
+### Internal
+
+* Significantly optimise ChunkEnumerator / FindGridsIntersecting in certain use cases by intersecting the grid's AABB with the local AABB to avoid iterating dummy chunks.
+
+
+## 210.1.1
+
+### Bugfixes
+
+* Fixed multiple recent bugs with key binding storage.
+
+### Other
+
+* Change default of `ButtonGroup.IsNoneSetAllowed` to `true`. This makes it default again to the previous (unintentional) behavior.
+
+
+## 210.1.0
+
+### New features
+
+* `NetUserId` implements `ISelfSerialize` so can be used in data fields.
+* `ButtonGroup.IsNoneSetAllowed` to allow a button group to have no buttons pressed by default.
+
+
+## 210.0.3
+
+
+## 210.0.2
+
+### Bugfixes
+
+* Revert changes to `TextureRect` too.
+
+
+## 210.0.1
+
+### Bugfixes
+
+* Revert changes to `TextureButton` that broke style property handling.
+
+
+## 210.0.0
+
+### New features
+
+* Controls can now hook before, after, and during rendering of their children.
+* IRenderHandle is now a public API, with the caveat that it's properties and methods are unstable.
+* ButtonGroup now exposes what buttons it contains, alongside which is currently pressed.
+* OptionButton has additional styleclasses, and has a hook for modifying it's internal buttons.
+* PanelContainer.GetStyleBox() is now protected rather than private.
+* TextureButton now uses a TextureRect instead of custom drawing code.
+* TextureRect has additional style properties exposed.
+    * A new property, TextureSizeTarget, was added, which allows specifying a size in virtual pixels that the control should attempt to draw at.
+    * Stretch mode is now a style property.
+    * Scale is now a style property.
+* Avalonia.Metadata.XmlnsDefinitionAttribute is now permitted by the sandbox.
+* Add MaxDimension property to Box2 to return the higher of the Width or Height.
+* Add GetLocalPosition to convert ScreenCoordinates to coordinates relative to the control. Ignores window.
+* Add GlobalRect and GlobalPixelRect for controls to get their UIBox2i in screen terms.
+* Add dotted line drawing to DrawingHandleScreen.
+* You can use `Subs.CVar()` from an entity systems to subscribe to CVar changes. This is more convenient than `IConfigurationManager.OnValueChanged` as it automatically unsubscribes on system shutdown.
+* There is now a built-in type serializer for `DateTime`, so you can put `DateTime`s in your data fields.
+* `System.Text.Unicode.UnicodeRange` and `UnicodeRanges` are now available in the sandbox.
+
+### Bugfixes
+
+* UI drawing now properly accounts for a control's draw routine potentially mangling the current matrix.
+* UI roots now properly update when the global stylesheet is changed. They previously only did so if they had a dedicated stylesheet (which is the one case where they would be unaffected by a global sheet update.
+
+
 ## 209.0.1
 
 ### Bugfixes

Robust.Analyzers.Tests/Aliases.cs

@@ -0,0 +1,8 @@
+// OH BOY. TURNS OUT IT GETS EVEN MORE CURSED.
+//
+// So because we're compiling a copy of Robust.Roslyn.Shared into every analyzer project,
+// the test project sees multiple copies of it. This would make it impossible to use.
+// UNLESS you use this obscure C# feature called "extern alias"
+// that I guarantee you you've never heard of before, and are now concerned about.
+
+extern alias SerializationGenerator;

Robust.Analyzers.Tests/ComponentPauseGeneratorTest.cs

@@ -0,0 +1,340 @@
+extern alias SerializationGenerator;
+using System.Linq;
+using System.Reflection;
+using Microsoft.CodeAnalysis;
+using Microsoft.CodeAnalysis.CSharp;
+using Microsoft.CodeAnalysis.Text;
+using NUnit.Framework;
+using SerializationGenerator::Robust.Roslyn.Shared;
+using SerializationGenerator::Robust.Serialization.Generator;
+
+namespace Robust.Analyzers.Tests;
+
+[TestFixture]
+[TestOf(typeof(ComponentPauseGenerator))]
+[Parallelizable(ParallelScope.All)]
+public sealed class ComponentPauseGeneratorTest
+{
+    private const string TypesCode = """
+        global using System;
+        global using Robust.Shared.Analyzers;
+        global using Robust.Shared.GameObjects;
+
+        namespace Robust.Shared.Analyzers
+        {
+            [AttributeUsage(AttributeTargets.Class, Inherited = false)]
+            public sealed class AutoGenerateComponentPauseAttribute : Attribute
+            {
+                public bool Dirty = false;
+            }
+
+            [AttributeUsage(AttributeTargets.Field | AttributeTargets.Property)]
+            public sealed class AutoPausedFieldAttribute : Attribute;
+
+            [AttributeUsage(AttributeTargets.Field | AttributeTargets.Property)]
+            public sealed class AutoNetworkedFieldAttribute : Attribute
+            {
+            }
+        }
+
+        namespace Robust.Shared.GameObjects
+        {
+            public interface IComponent;
+        }
+        """;
+
+    [Test]
+    public void TestBasic()
+    {
+        var result = RunGenerator("""
+            [AutoGenerateComponentPause]
+            public sealed partial class FooComponent : IComponent
+            {
+                [AutoPausedField]
+                public TimeSpan Foo;
+            }
+            """);
+
+        ExpectNoDiagnostics(result);
+        ExpectSource(
+            result,
+            """
+            // <auto-generated />
+
+            using Robust.Shared.GameObjects;
+
+            public partial class FooComponent
+            {
+            [RobustAutoGenerated]
+            public sealed class FooComponent_AutoPauseSystem : EntitySystem
+            {
+                public override void Initialize()
+                {
+                    SubscribeLocalEvent<FooComponent, EntityUnpausedEvent>(OnEntityUnpaused);
+                }
+
+                private void OnEntityUnpaused(EntityUid uid, FooComponent component, ref EntityUnpausedEvent args)
+                {
+                    component.Foo += args.PausedTime;
+                }
+            }
+            }
+
+            """);
+    }
+
+    [Test]
+    public void TestNullable()
+    {
+        var result = RunGenerator("""
+            [AutoGenerateComponentPause]
+            public sealed partial class FooComponent : IComponent
+            {
+                [AutoPausedField]
+                public TimeSpan? Foo;
+            }
+            """);
+
+        ExpectNoDiagnostics(result);
+        ExpectSource(
+            result,
+            """
+            // <auto-generated />
+
+            using Robust.Shared.GameObjects;
+
+            public partial class FooComponent
+            {
+            [RobustAutoGenerated]
+            public sealed class FooComponent_AutoPauseSystem : EntitySystem
+            {
+                public override void Initialize()
+                {
+                    SubscribeLocalEvent<FooComponent, EntityUnpausedEvent>(OnEntityUnpaused);
+                }
+
+                private void OnEntityUnpaused(EntityUid uid, FooComponent component, ref EntityUnpausedEvent args)
+                {
+                    if (component.Foo.HasValue)
+                        component.Foo = component.Foo.Value + args.PausedTime;
+                }
+            }
+            }
+
+            """);
+    }
+
+    [Test]
+    public void TestAutoState()
+    {
+        var result = RunGenerator("""
+            [AutoGenerateComponentPause]
+            public sealed partial class FooComponent : IComponent
+            {
+                [AutoPausedField, AutoNetworkedField]
+                public TimeSpan Foo;
+            }
+            """);
+
+        ExpectNoDiagnostics(result);
+        ExpectSource(
+            result,
+            """
+            // <auto-generated />
+
+            using Robust.Shared.GameObjects;
+
+            public partial class FooComponent
+            {
+            [RobustAutoGenerated]
+            public sealed class FooComponent_AutoPauseSystem : EntitySystem
+            {
+                public override void Initialize()
+                {
+                    SubscribeLocalEvent<FooComponent, EntityUnpausedEvent>(OnEntityUnpaused);
+                }
+
+                private void OnEntityUnpaused(EntityUid uid, FooComponent component, ref EntityUnpausedEvent args)
+                {
+                    component.Foo += args.PausedTime;
+                    Dirty(uid, component);
+                }
+            }
+            }
+
+            """);
+    }
+
+    [Test]
+    public void TestExplicitDirty()
+    {
+        var result = RunGenerator("""
+            [AutoGenerateComponentPause(Dirty = true)]
+            public sealed partial class FooComponent : IComponent
+            {
+                [AutoPausedField]
+                public TimeSpan Foo;
+            }
+            """);
+
+        ExpectNoDiagnostics(result);
+        ExpectSource(
+            result,
+            """
+            // <auto-generated />
+
+            using Robust.Shared.GameObjects;
+
+            public partial class FooComponent
+            {
+            [RobustAutoGenerated]
+            public sealed class FooComponent_AutoPauseSystem : EntitySystem
+            {
+                public override void Initialize()
+                {
+                    SubscribeLocalEvent<FooComponent, EntityUnpausedEvent>(OnEntityUnpaused);
+                }
+
+                private void OnEntityUnpaused(EntityUid uid, FooComponent component, ref EntityUnpausedEvent args)
+                {
+                    component.Foo += args.PausedTime;
+                    Dirty(uid, component);
+                }
+            }
+            }
+
+            """);
+    }
+
+    [Test]
+    public void TestDiagnosticNotIComponent()
+    {
+        var result = RunGenerator("""
+            [AutoGenerateComponentPause]
+            public sealed partial class FooComponent
+            {
+                [AutoPausedField]
+                public TimeSpan Foo;
+            }
+            """);
+
+        ExpectNoSource(result);
+        ExpectDiagnostics(result, [
+            (Diagnostics.IdComponentPauseNotComponent, new LinePositionSpan(new LinePosition(1, 28), new LinePosition(1, 40)))
+        ]);
+    }
+
+    [Test]
+    public void TestDiagnosticNoFields()
+    {
+        var result = RunGenerator("""
+            [AutoGenerateComponentPause]
+            public sealed partial class FooComponent : IComponent
+            {
+                public TimeSpan Foo;
+            }
+            """);
+
+        ExpectNoSource(result);
+        ExpectDiagnostics(result, [
+            (Diagnostics.IdComponentPauseNoFields, new LinePositionSpan(new LinePosition(1, 28), new LinePosition(1, 40)))
+        ]);
+    }
+
+    [Test]
+    public void TestDiagnosticNoParentAttribute()
+    {
+        var result = RunGenerator("""
+            public sealed partial class FooComponent : IComponent
+            {
+                [AutoPausedField]
+                public TimeSpan Foo, Fooz;
+
+                [AutoPausedField]
+                public TimeSpan Bar { get; set; }
+            }
+            """);
+
+        ExpectNoSource(result);
+        ExpectDiagnostics(result, [
+            (Diagnostics.IdComponentPauseNoParentAttribute, new LinePositionSpan(new LinePosition(3, 20), new LinePosition(3, 23))),
+            (Diagnostics.IdComponentPauseNoParentAttribute, new LinePositionSpan(new LinePosition(3, 25), new LinePosition(3, 29))),
+            (Diagnostics.IdComponentPauseNoParentAttribute, new LinePositionSpan(new LinePosition(6, 20), new LinePosition(6, 23)))
+        ]);
+    }
+
+    [Test]
+    public void TestDiagnosticWrongType()
+    {
+        var result = RunGenerator("""
+            [AutoGenerateComponentPause]
+            public sealed partial class FooComponent : IComponent
+            {
+                [AutoPausedField]
+                public int Foo, Fooz;
+
+                [AutoPausedField]
+                public int Bar { get; set; }
+            }
+            """);
+
+        ExpectNoSource(result);
+        ExpectDiagnostics(result, [
+            (Diagnostics.IdComponentPauseWrongTypeAttribute, new LinePositionSpan(new LinePosition(4, 15), new LinePosition(4, 18))),
+            (Diagnostics.IdComponentPauseWrongTypeAttribute, new LinePositionSpan(new LinePosition(4, 20), new LinePosition(4, 24))),
+            (Diagnostics.IdComponentPauseWrongTypeAttribute, new LinePositionSpan(new LinePosition(7, 15), new LinePosition(7, 18)))
+        ]);
+    }
+
+    private static void ExpectSource(GeneratorRunResult result, string expected)
+    {
+        Assert.That(result.GeneratedSources, Has.Length.EqualTo(1));
+
+        var source = result.GeneratedSources[0];
+
+        Assert.That(source.SourceText.ToString(), Is.EqualTo(expected));
+    }
+
+    private static void ExpectNoSource(GeneratorRunResult result)
+    {
+        Assert.That(result.GeneratedSources, Is.Empty);
+    }
+
+    private static void ExpectNoDiagnostics(GeneratorRunResult result)
+    {
+        Assert.That(result.Diagnostics, Is.Empty);
+    }
+
+    private static void ExpectDiagnostics(GeneratorRunResult result, (string code, LinePositionSpan span)[] diagnostics)
+    {
+        Assert.Multiple(() =>
+        {
+            Assert.That(result.Diagnostics, Has.Length.EqualTo(diagnostics.Length));
+            foreach (var (code, span) in diagnostics)
+            {
+                Assert.That(
+                    result.Diagnostics.Any(x => x.Id == code && x.Location.GetLineSpan().Span == span),
+                    $"Expected diagnostic with code {code} and location {span}");
+            }
+        });
+    }
+
+    private static GeneratorRunResult RunGenerator(string source)
+    {
+        var compilation = (Compilation)CSharpCompilation.Create("compilation",
+            new[]
+            {
+                CSharpSyntaxTree.ParseText(source, path: "Source.cs"),
+                CSharpSyntaxTree.ParseText(TypesCode, path: "Types.cs")
+            },
+            new[] { MetadataReference.CreateFromFile(typeof(Binder).GetTypeInfo().Assembly.Location) },
+            new CSharpCompilationOptions(OutputKind.DynamicallyLinkedLibrary));
+
+        var generator = new ComponentPauseGenerator();
+        GeneratorDriver driver = CSharpGeneratorDriver.Create(generator);
+        driver = driver.RunGeneratorsAndUpdateCompilation(compilation, out var newCompilation, out _);
+        var result = driver.GetRunResult();
+
+        return result.Results[0];
+    }
+}

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

@@ -1,4 +1,8 @@
 <Project Sdk="Microsoft.NET.Sdk">
+  <PropertyGroup>
+    <SkipRobustAnalyzer>true</SkipRobustAnalyzer>
+  </PropertyGroup>
+
   <Import Project="..\MSBuild\Robust.Properties.targets"/>
   <Import Project="..\MSBuild\Robust.Engine.props"/>
 
@@ -23,5 +27,6 @@
 
   <ItemGroup>
     <ProjectReference Include="..\Robust.Analyzers\Robust.Analyzers.csproj"/>
+    <ProjectReference Include="..\Robust.Serialization.Generator\Robust.Serialization.Generator.csproj" Aliases="SerializationGenerator" />
   </ItemGroup>
 </Project>

Robust.Analyzers/AccessAnalyzer.cs

@@ -5,6 +5,7 @@ using System.Linq;
 using Microsoft.CodeAnalysis;
 using Microsoft.CodeAnalysis.Diagnostics;
 using Microsoft.CodeAnalysis.Operations;
+using Robust.Roslyn.Shared;
 using Robust.Shared.Analyzers.Implementation;
 
 namespace Robust.Analyzers

Robust.Analyzers/ByRefEventAnalyzer.cs

@@ -4,6 +4,7 @@ using System.Linq;
 using Microsoft.CodeAnalysis;
 using Microsoft.CodeAnalysis.Diagnostics;
 using Microsoft.CodeAnalysis.Operations;
+using Robust.Roslyn.Shared;
 using static Microsoft.CodeAnalysis.SymbolEqualityComparer;
 
 namespace Robust.Analyzers;
@@ -16,7 +17,7 @@ public sealed class ByRefEventAnalyzer : DiagnosticAnalyzer
     private static readonly DiagnosticDescriptor ByRefEventSubscribedByValueRule = new(
         Diagnostics.IdByRefEventSubscribedByValue,
         "By-ref event subscribed to by value",
-        "Tried to subscribe to a by-ref event '{0}' by value.",
+        "Tried to subscribe to a by-ref event '{0}' by value",
         "Usage",
         DiagnosticSeverity.Error,
         true,
@@ -26,7 +27,7 @@ public sealed class ByRefEventAnalyzer : DiagnosticAnalyzer
     private static readonly DiagnosticDescriptor ByRefEventRaisedByValueRule = new(
         Diagnostics.IdByRefEventRaisedByValue,
         "By-ref event raised by value",
-        "Tried to raise a by-ref event '{0}' by value.",
+        "Tried to raise a by-ref event '{0}' by value",
         "Usage",
         DiagnosticSeverity.Error,
         true,
@@ -36,7 +37,7 @@ public sealed class ByRefEventAnalyzer : DiagnosticAnalyzer
     private static readonly DiagnosticDescriptor ByValueEventRaisedByRefRule = new(
         Diagnostics.IdValueEventRaisedByRef,
         "Value event raised by-ref",
-        "Tried to raise a value event '{0}' by-ref.",
+        "Tried to raise a value event '{0}' by-ref",
         "Usage",
         DiagnosticSeverity.Error,
         true,

Robust.Analyzers/DataDefinitionAnalyzer.cs

@@ -5,6 +5,7 @@ using Microsoft.CodeAnalysis;
 using Microsoft.CodeAnalysis.CSharp;
 using Microsoft.CodeAnalysis.CSharp.Syntax;
 using Microsoft.CodeAnalysis.Diagnostics;
+using Robust.Roslyn.Shared;
 
 namespace Robust.Analyzers;
 
@@ -18,7 +19,7 @@ public sealed class DataDefinitionAnalyzer : DiagnosticAnalyzer
     private static readonly DiagnosticDescriptor DataDefinitionPartialRule = new(
         Diagnostics.IdDataDefinitionPartial,
         "Type must be partial",
-        "Type {0} is a DataDefinition but is not partial.",
+        "Type {0} is a DataDefinition but is not partial",
         "Usage",
         DiagnosticSeverity.Error,
         true,
@@ -28,7 +29,7 @@ public sealed class DataDefinitionAnalyzer : DiagnosticAnalyzer
     private static readonly DiagnosticDescriptor NestedDataDefinitionPartialRule = new(
         Diagnostics.IdNestedDataDefinitionPartial,
         "Type must be partial",
-        "Type {0} contains nested data definition {1} but is not partial.",
+        "Type {0} contains nested data definition {1} but is not partial",
         "Usage",
         DiagnosticSeverity.Error,
         true,
@@ -38,7 +39,7 @@ public sealed class DataDefinitionAnalyzer : DiagnosticAnalyzer
     private static readonly DiagnosticDescriptor DataFieldWritableRule = new(
         Diagnostics.IdDataFieldWritable,
         "Data field must not be readonly",
-        "Data field {0} in data definition {1} is readonly.",
+        "Data field {0} in data definition {1} is readonly",
         "Usage",
         DiagnosticSeverity.Error,
         true,
@@ -48,7 +49,7 @@ public sealed class DataDefinitionAnalyzer : DiagnosticAnalyzer
     private static readonly DiagnosticDescriptor DataFieldPropertyWritableRule = new(
         Diagnostics.IdDataFieldPropertyWritable,
         "Data field property must have a setter",
-        "Data field property {0} in data definition {1} does not have a setter.",
+        "Data field property {0} in data definition {1} does not have a setter",
         "Usage",
         DiagnosticSeverity.Error,
         true,

Robust.Analyzers/DataDefinitionFixer.cs

@@ -9,7 +9,7 @@ using Microsoft.CodeAnalysis.CodeFixes;
 using Microsoft.CodeAnalysis.CSharp;
 using Microsoft.CodeAnalysis.CSharp.Syntax;
 using static Microsoft.CodeAnalysis.CSharp.SyntaxKind;
-using static Robust.Analyzers.Diagnostics;
+using static Robust.Roslyn.Shared.Diagnostics;
 
 namespace Robust.Analyzers;
 

Robust.Analyzers/ExplicitInterfaceAnalyzer.cs

@@ -10,6 +10,7 @@ using Microsoft.CodeAnalysis.CodeFixes;
 using Microsoft.CodeAnalysis.CSharp;
 using Microsoft.CodeAnalysis.CSharp.Syntax;
 using Microsoft.CodeAnalysis.Diagnostics;
+using Robust.Roslyn.Shared;
 using Document = Microsoft.CodeAnalysis.Document;
 
 namespace Robust.Analyzers

Robust.Analyzers/ExplicitVirtualAnalyzer.cs

@@ -5,6 +5,7 @@ using Microsoft.CodeAnalysis;
 using Microsoft.CodeAnalysis.CSharp;
 using Microsoft.CodeAnalysis.CSharp.Syntax;
 using Microsoft.CodeAnalysis.Diagnostics;
+using Robust.Roslyn.Shared;
 
 namespace Robust.Analyzers;
 

Robust.Analyzers/MeansImplicitAssigmentSuppressor.cs

@@ -2,6 +2,7 @@ using System.Collections.Immutable;
 using System.Linq;
 using Microsoft.CodeAnalysis;
 using Microsoft.CodeAnalysis.Diagnostics;
+using Robust.Roslyn.Shared;
 
 namespace Robust.Analyzers
 {

Robust.Analyzers/NotNullableFlagAnalyzer.cs

@@ -3,6 +3,7 @@ using System.Linq;
 using Microsoft.CodeAnalysis;
 using Microsoft.CodeAnalysis.Diagnostics;
 using Microsoft.CodeAnalysis.Operations;
+using Robust.Roslyn.Shared;
 
 namespace Robust.Analyzers;
 
@@ -31,7 +32,7 @@ public sealed class NotNullableFlagAnalyzer : DiagnosticAnalyzer
 
     private static readonly DiagnosticDescriptor InvalidNotNullableImplementationRule = new (
         Diagnostics.IdInvalidNotNullableFlagImplementation,
-        "Invalid NotNullable flag implementation.",
+        "Invalid NotNullable flag implementation",
         "NotNullable flag is either not typed as bool, or does not have a default value equaling false",
         "Usage",
         DiagnosticSeverity.Error,
@@ -41,7 +42,7 @@ public sealed class NotNullableFlagAnalyzer : DiagnosticAnalyzer
     private static readonly DiagnosticDescriptor InvalidNotNullableTypeRule = new (
         Diagnostics.IdInvalidNotNullableFlagType,
         "Failed to resolve type parameter",
-        "Failed to resolve type parameter \"{0}\".",
+        "Failed to resolve type parameter \"{0}\"",
         "Usage",
         DiagnosticSeverity.Error,
         true,
@@ -49,7 +50,7 @@ public sealed class NotNullableFlagAnalyzer : DiagnosticAnalyzer
 
     private static readonly DiagnosticDescriptor NotNullableFlagValueTypeRule = new (
         Diagnostics.IdNotNullableFlagValueType,
-        "NotNullable flag not supported for value types.",
+        "NotNullable flag not supported for value types",
         "Value types as generic arguments are not supported for NotNullable flags",
         "Usage",
         DiagnosticSeverity.Error,

Robust.Analyzers/PreferGenericVariantAnalyzer.cs

@@ -11,6 +11,7 @@ using Microsoft.CodeAnalysis.CSharp;
 using Microsoft.CodeAnalysis.CSharp.Syntax;
 using Microsoft.CodeAnalysis.Diagnostics;
 using Microsoft.CodeAnalysis.Operations;
+using Robust.Roslyn.Shared;
 
 namespace Robust.Analyzers;
 

Robust.Analyzers/Robust.Analyzers.csproj

@@ -1,17 +1,5 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
-  <PropertyGroup>
-    <TargetFramework>netstandard2.0</TargetFramework>
-    <LangVersion>10</LangVersion>
-    <ManagePackageVersionsCentrally>true</ManagePackageVersionsCentrally>
-  </PropertyGroup>
-
-  <ItemGroup>
-    <PackageReference Include="Microsoft.CodeAnalysis.CSharp" PrivateAssets="all" />
-    <PackageReference Include="Microsoft.CodeAnalysis.Analyzers" PrivateAssets="all" />
-    <PackageReference Include="Microsoft.CodeAnalysis.Workspaces.Common" />
-  </ItemGroup>
-
   <ItemGroup>
     <!-- Needed for NotNullableFlagAnalyzer. -->
     <Compile Include="..\Robust.Shared\Analyzers\NotNullableFlagAttribute.cs" />
@@ -28,4 +16,10 @@
     <Compile Include="..\Robust.Shared\Analyzers\PreferGenericVariantAttribute.cs" />
   </ItemGroup>
 
+  <Import Project="../Robust.Roslyn.Shared/Robust.Roslyn.Shared.props" />
+
+  <PropertyGroup>
+    <Nullable>disable</Nullable>
+  </PropertyGroup>
+
 </Project>

Robust.Analyzers/SerializableAnalyzer.cs

@@ -10,6 +10,7 @@ using Microsoft.CodeAnalysis.CodeFixes;
 using Microsoft.CodeAnalysis.CSharp;
 using Microsoft.CodeAnalysis.CSharp.Syntax;
 using Microsoft.CodeAnalysis.Diagnostics;
+using Robust.Roslyn.Shared;
 
 namespace Robust.Analyzers
 {

Robust.Analyzers/TaskResultAnalyzer.cs

@@ -3,6 +3,7 @@ using System.Diagnostics.CodeAnalysis;
 using Microsoft.CodeAnalysis;
 using Microsoft.CodeAnalysis.Diagnostics;
 using Microsoft.CodeAnalysis.Operations;
+using Robust.Roslyn.Shared;
 
 namespace Robust.Analyzers;
 

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

@@ -1,19 +1,17 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
-    <PropertyGroup>
-        <TargetFramework>netstandard2.0</TargetFramework>
-      <ManagePackageVersionsCentrally>true</ManagePackageVersionsCentrally>
-    </PropertyGroup>
-
-  <ItemGroup>
-    <PackageReference Include="Microsoft.CodeAnalysis.CSharp" PrivateAssets="all" />
-    <PackageReference Include="Microsoft.CodeAnalysis.Analyzers" PrivateAssets="all" />
-  </ItemGroup>
-
   <ItemGroup>
     <Compile Link="XamlX\filename" Include="../XamlX/src/XamlX/**/*.cs" />
     <Compile Remove="../XamlX/src/XamlX/**/SreTypeSystem.cs" />
     <Compile Remove="../XamlX/src/XamlX/obj/**" />
     <Compile Include="..\Robust.Client\UserInterface\ControlPropertyAccess.cs" />
   </ItemGroup>
+
+  <Import Project="../Robust.Roslyn.Shared/Robust.Roslyn.Shared.props" />
+
+  <PropertyGroup>
+    <!-- XamlX doesn't do NRTs. -->
+    <Nullable>disable</Nullable>
+  </PropertyGroup>
+
 </Project>

Robust.Client/Audio/AudioOverlay.cs

@@ -39,7 +39,7 @@ public sealed class AudioOverlay : Overlay
 
     protected internal override void Draw(in OverlayDrawArgs args)
     {
-        var localPlayer = _playerManager.LocalPlayer?.ControlledEntity;
+        var localPlayer = _playerManager.LocalEntity;
 
         if (args.ViewportControl == null || localPlayer == null)
             return;

Robust.Client/Audio/AudioSystem.cs

@@ -106,8 +106,8 @@ public sealed partial class AudioSystem : SharedAudioSystem
         SubscribeNetworkEvent<PlayAudioEntityMessage>(OnEntityAudio);
         SubscribeNetworkEvent<PlayAudioPositionalMessage>(OnEntityCoordinates);
 
-        CfgManager.OnValueChanged(CVars.AudioAttenuation, OnAudioAttenuation, true);
-        CfgManager.OnValueChanged(CVars.AudioRaycastLength, OnRaycastLengthChanged, true);
+        Subs.CVar(CfgManager, CVars.AudioAttenuation, OnAudioAttenuation, true);
+        Subs.CVar(CfgManager, CVars.AudioRaycastLength, OnRaycastLengthChanged, true);
     }
 
     private void OnAudioState(EntityUid uid, AudioComponent component, ref AfterAutoHandleStateEvent args)
@@ -133,13 +133,6 @@ public sealed partial class AudioSystem : SharedAudioSystem
         _audio.SetMasterGain(value);
     }
 
-    public override void Shutdown()
-    {
-        CfgManager.UnsubValueChanged(CVars.AudioAttenuation, OnAudioAttenuation);
-        CfgManager.UnsubValueChanged(CVars.AudioRaycastLength, OnRaycastLengthChanged);
-        base.Shutdown();
-    }
-
     private void OnAudioPaused(EntityUid uid, AudioComponent component, ref EntityPausedEvent args)
     {
         component.Pause();

Robust.Client/Audio/Midi/MidiManager.cs

@@ -114,7 +114,7 @@ internal sealed partial class MidiManager : IMidiManager
         "/usr/share/sounds/sf2/TimGM6mb.sf2",
     };
 
-    private const string WindowsSoundfont = @"C:\WINDOWS\system32\drivers\gm.dls";
+    private static readonly string WindowsSoundfont = $@"{Environment.GetEnvironmentVariable("SystemRoot")}\system32\drivers\gm.dls";
 
     private const string OsxSoundfont =
         "/System/Library/Components/CoreAudio.component/Contents/Resources/gs_instruments.dls";

Robust.Client/BaseClient.cs

@@ -229,7 +229,7 @@ namespace Robust.Client
 
             // Don't invoke PlayerLeaveServer if PlayerJoinedServer & GameStartedSetup hasn't been called yet.
             if (RunLevel > ClientRunLevel.Connecting)
-                PlayerLeaveServer?.Invoke(this, new PlayerEventArgs(_playMan.LocalPlayer?.Session));
+                PlayerLeaveServer?.Invoke(this, new PlayerEventArgs(_playMan.LocalSession));
 
             LastDisconnectReason = args.Reason;
             GameStoppedReset();

Robust.Client/Console/ClientConsoleHost.cs

@@ -188,7 +188,7 @@ namespace Robust.Client.Console
             }
 
             args.RemoveAt(0);
-            var shell = new ConsoleShell(this, session ?? _player.LocalPlayer?.Session, session == null);
+            var shell = new ConsoleShell(this, session ?? _player.LocalSession, session == null);
             var cmdArgs = args.ToArray();
 
             AnyCommandExecuted?.Invoke(shell, commandName, command, cmdArgs);
@@ -200,8 +200,7 @@ namespace Robust.Client.Console
             // 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
+            return _player.LocalSession is not { Status: > SessionStatus.Connecting }
                    || _conGroup.CanCommand(cmdName);
         }
 

Robust.Client/Console/Commands/ClientSpawnCommand.cs

@@ -16,8 +16,7 @@ namespace Robust.Client.Console.Commands
 
         public override void Execute(IConsoleShell shell, string argStr, string[] args)
         {
-            var controlled = _playerManager.LocalPlayer?.ControlledEntity ?? EntityUid.Invalid;
-            if (controlled == EntityUid.Invalid)
+            if (_playerManager.LocalEntity is not { } controlled)
             {
                 shell.WriteLine("You don't have an attached entity.");
                 return;

Robust.Client/Debugging/DebugPhysicsSystem.cs

@@ -420,7 +420,7 @@ namespace Robust.Client.Debugging
                 if (mapPos.MapId != args.MapId)
                     return;
 
-                var player = _playerManager.LocalPlayer?.ControlledEntity;
+                var player = _playerManager.LocalEntity;
 
                 if (!_entityManager.TryGetComponent<TransformComponent>(player, out var playerXform) ||
                     playerXform.MapID != args.MapId)

Robust.Client/GameObjects/ClientEntityManager.Network.cs

@@ -42,6 +42,8 @@ public sealed partial class ClientEntityManager
         var pending = PendingNetEntityStates.GetOrNew(nEntity);
         pending.Add((typeof(T), callerEntity));
 
+
+
         return entity.Item1;
     }
 

Robust.Client/GameObjects/ClientEntityManager.cs

@@ -221,7 +221,7 @@ namespace Robust.Client.GameObjects
         public void DispatchReceivedNetworkMsg(EntityEventArgs msg)
         {
             var sessionType = typeof(EntitySessionMessage<>).MakeGenericType(msg.GetType());
-            var sessionMsg = Activator.CreateInstance(sessionType, new EntitySessionEventArgs(_playerManager.LocalPlayer!.Session), msg)!;
+            var sessionMsg = Activator.CreateInstance(sessionType, new EntitySessionEventArgs(_playerManager.LocalSession!), msg)!;
             ReceivedSystemMessage?.Invoke(this, msg);
             ReceivedSystemMessage?.Invoke(this, sessionMsg);
         }

Robust.Client/GameObjects/EntitySystems/InputSystem.cs

@@ -105,12 +105,10 @@ namespace Robust.Client.GameObjects
         /// <param name="inputCmd">Input command to handle as predicted.</param>
         public void PredictInputCommand(IFullInputCmdMessage inputCmd)
         {
-            DebugTools.AssertNotNull(_playerManager.LocalPlayer);
-
             var keyFunc = _inputManager.NetworkBindMap.KeyFunctionName(inputCmd.InputFunctionId);
 
             Predicted = true;
-            var session = _playerManager.LocalPlayer!.Session;
+            var session = _playerManager.LocalSession;
             foreach (var handler in BindRegistry.GetHandlers(keyFunc))
             {
                 if (handler.HandleCmdMessage(EntityManager, session, inputCmd))
@@ -145,27 +143,22 @@ namespace Robust.Client.GameObjects
 
         private void GenerateInputCommand(IConsoleShell shell, string argstr, string[] args)
         {
-            var localPlayer = _playerManager.LocalPlayer;
-            if(localPlayer is null)
-                return;
-
-            var pent = localPlayer.ControlledEntity;
-            if(pent is null)
+            if (_playerManager.LocalEntity is not { } pent)
                 return;
 
             BoundKeyFunction keyFunction = new BoundKeyFunction(args[0]);
             BoundKeyState state = args[1] == "u" ? BoundKeyState.Up: BoundKeyState.Down;
 
-            var pxform = Transform(pent.Value);
+            var pxform = Transform(pent);
             var wPos = pxform.WorldPosition + new Vector2(float.Parse(args[2]), float.Parse(args[3]));
-            var coords = EntityCoordinates.FromMap(EntityManager, pent.Value, new MapCoordinates(wPos, pxform.MapID));
+            var coords = EntityCoordinates.FromMap(EntityManager, pent, new MapCoordinates(wPos, pxform.MapID));
 
             var funcId = _inputManager.NetworkBindMap.KeyFunctionID(keyFunction);
 
             var message = new FullInputCmdMessage(_timing.CurTick, _timing.TickFraction, funcId, state,
                 GetNetCoordinates(coords), new ScreenCoordinates(0, 0, default), NetEntity.Invalid);
 
-            HandleInputCommand(localPlayer.Session, keyFunction, message);
+            HandleInputCommand(_playerManager.LocalSession, keyFunction, message);
         }
 
         private void OnAttachedEntityChanged(LocalPlayerAttachedEvent message)
@@ -208,11 +201,8 @@ namespace Robust.Client.GameObjects
         /// </summary>
         public void SetEntityContextActive()
         {
-            var controlled = _playerManager.LocalPlayer?.ControlledEntity ?? EntityUid.Invalid;
-            if (controlled == EntityUid.Invalid)
-            {
+            if (_playerManager.LocalEntity is not { } controlled)
                 return;
-            }
 
             SetEntityContextActive(_inputManager, controlled);
         }

Robust.Client/GameObjects/EntitySystems/SpriteSystem.cs

@@ -62,7 +62,7 @@ namespace Robust.Client.GameObjects
             SubscribeLocalEvent<SpriteComponent, SpriteUpdateInertEvent>(QueueUpdateInert);
             SubscribeLocalEvent<SpriteComponent, ComponentInit>(OnInit);
 
-            _cfg.OnValueChanged(CVars.RenderSpriteDirectionBias, OnBiasChanged, true);
+            Subs.CVar(_cfg, CVars.RenderSpriteDirectionBias, OnBiasChanged, true);
             _sawmill = _logManager.GetSawmill("sprite");
         }
 
@@ -72,12 +72,6 @@ namespace Robust.Client.GameObjects
             QueueUpdateInert(uid, component);
         }
 
-        public override void Shutdown()
-        {
-            base.Shutdown();
-            _cfg.UnsubValueChanged(CVars.RenderSpriteDirectionBias, OnBiasChanged);
-        }
-
         private void OnBiasChanged(double value)
         {
             SpriteComponent.DirectionBias = value;

Robust.Client/GameObjects/EntitySystems/UserInterfaceSystem.cs

@@ -29,10 +29,7 @@ namespace Robust.Client.GameObjects
 
             var uiKey = ev.UiKey;
             var message = ev.Message;
-            // This should probably not happen at this point, but better make extra sure!
-            if (_playerManager.LocalPlayer != null)
-                message.Session = _playerManager.LocalPlayer.Session;
-
+            message.Session = _playerManager.LocalSession!;
             message.Entity = GetNetEntity(uid);
             message.UiKey = uiKey;
 
@@ -75,8 +72,7 @@ namespace Robust.Client.GameObjects
             boundInterface.Open();
             uiComp.OpenInterfaces[uiKey] = boundInterface;
 
-            var playerSession = _playerManager.LocalPlayer?.Session;
-            if (playerSession != null)
+            if (_playerManager.LocalSession is { } playerSession)
             {
                 uiComp.Interfaces[uiKey]._subscribedSessions.Add(playerSession);
                 RaiseLocalEvent(uid, new BoundUIOpenedEvent(uiKey, uid, playerSession), true);

Robust.Client/GameObjects/EntitySystems/VelocityDebugSystem.cs

@@ -35,7 +35,7 @@ namespace Robust.Client.GameObjects
                 return;
             }
 
-            var player = _playerManager.LocalPlayer?.ControlledEntity;
+            var player = _playerManager.LocalEntity;
 
             if (player == null || !EntityManager.TryGetComponent(player.Value, out PhysicsComponent? body))
             {

Robust.Client/GameStates/ClientGameStateManager.cs

@@ -232,9 +232,9 @@ namespace Robust.Client.GameStates
                 return default;
             }
 
-            DebugTools.AssertNotNull(_players.LocalPlayer);
+            DebugTools.Assert(_players.LocalSession != null);
 
-            var evArgs = new EntitySessionEventArgs(_players.LocalPlayer!.Session);
+            var evArgs = new EntitySessionEventArgs(_players.LocalSession);
             _pendingSystemMessages.Enqueue((_nextInputCmdSeq, _timing.CurTick, message,
                 new EntitySessionMessage<T>(evArgs, message)));
 

Robust.Client/GameStates/NetGraphOverlay.cs

@@ -313,7 +313,7 @@ namespace Robust.Client.GameStates
 
                 if (args.Length == 0)
                 {
-                    entity = _playerManager.LocalPlayer?.ControlledEntity ?? EntityUid.Invalid;
+                    entity = _playerManager.LocalEntity ?? EntityUid.Invalid;
                 }
                 else if (!NetEntity.TryParse(args[0], out var netEntity) || !_entManager.TryGetEntity(netEntity, out entity))
                 {

Robust.Client/Graphics/Drawing/DrawingHandleBase.cs

@@ -3,7 +3,7 @@ using System.Diagnostics;
 using System.Numerics;
 using System.Runtime.CompilerServices;
 using System.Runtime.InteropServices;
-using Robust.Shared.Graphics;
+using System.Runtime.Intrinsics;
 using Robust.Shared.Maths;
 
 namespace Robust.Client.Graphics
@@ -100,12 +100,43 @@ namespace Robust.Client.Graphics
             DrawPrimitives(primitiveTopology, White, indices, drawVertices);
         }
 
-        private void PadVerticesV2(ReadOnlySpan<Vector2> input, Span<DrawVertexUV2DColor> output, Color color)
+        private static void PadVerticesV2(ReadOnlySpan<Vector2> input, Span<DrawVertexUV2DColor> output, Color color)
         {
-            Color colorLinear = Color.FromSrgb(color);
-            for (var i = 0; i < output.Length; i++)
+            if (input.Length == 0)
+                return;
+
+            if (input.Length != output.Length)
             {
-                output[i] = new DrawVertexUV2DColor(input[i], new Vector2(0.5f, 0.5f), colorLinear);
+                throw new InvalidOperationException("Invalid lengths!");
+            }
+
+            var colorLinear = Color.FromSrgb(color);
+            var colorVec = Unsafe.As<Color, Vector128<float>>(ref colorLinear);
+            var uvVec = Vector128.Create(0, 0, 0.5f, 0.5f);
+            var maskVec = Vector128.Create(0xFFFFFFFF, 0xFFFFFFFF, 0, 0).AsSingle();
+
+            var simdVectors = (nuint)(input.Length / 2);
+            ref readonly var srcBase = ref Unsafe.As<Vector2, float>(ref Unsafe.AsRef(in input[0]));
+            ref var dstBase = ref Unsafe.As<DrawVertexUV2DColor, float>(ref output[0]);
+
+            for (nuint i = 0; i < simdVectors; i++)
+            {
+                var positions = Vector128.LoadUnsafe(in srcBase, i * 4);
+
+                var posColorLower = (positions & maskVec) | uvVec;
+                var posColorUpper = (Vector128.Shuffle(positions, Vector128.Create(2, 3, 0, 0)) & maskVec) | uvVec;
+
+                posColorLower.StoreUnsafe(ref dstBase, i * 16);
+                colorVec.StoreUnsafe(ref dstBase, i * 16 + 4);
+                posColorUpper.StoreUnsafe(ref dstBase, i * 16 + 8);
+                colorVec.StoreUnsafe(ref dstBase, i * 16 + 12);
+            }
+
+            var lastPos = (int)simdVectors * 2;
+            if (lastPos != output.Length)
+            {
+                // Odd number of vertices. Handle the last manually.
+                output[lastPos] = new DrawVertexUV2DColor(input[lastPos], new Vector2(0.5f, 0.5f), colorLinear);
             }
         }
 

Robust.Client/Graphics/IRenderHandle.cs

@@ -6,7 +6,10 @@ using Robust.Shared.Maths;
 
 namespace Robust.Client.Graphics
 {
-    internal interface IRenderHandle
+    /// <remarks>
+    ///     Unstable API. Likely to break hard during renderer rewrite if you rely on it.
+    /// </remarks>
+    public interface IRenderHandle
     {
         DrawingHandleScreen DrawingHandleScreen { get; }
         DrawingHandleWorld DrawingHandleWorld { get; }

Robust.Client/Input/IInputManager.cs

@@ -40,7 +40,7 @@ namespace Robust.Client.Input
         void KeyDown(KeyEventArgs e);
         void KeyUp(KeyEventArgs e);
 
-        IKeyBinding RegisterBinding(in KeyBindingRegistration reg, bool markModified=true);
+        IKeyBinding RegisterBinding(in KeyBindingRegistration reg, bool markModified=true, bool invalid=false);
 
         void RemoveBinding(IKeyBinding binding, bool markModified=true);
 

Robust.Client/Input/InputManager.cs

@@ -126,7 +126,7 @@ namespace Robust.Client.Input
             {
                 try
                 {
-                    LoadKeyFile(path, true);
+                    LoadKeyFile(path, false, true);
                 }
                 catch (Exception e)
                 {
@@ -136,7 +136,7 @@ namespace Robust.Client.Input
 
             if (_resourceMan.ContentFileExists(path))
             {
-                LoadKeyFile(path, false);
+                LoadKeyFile(path, true);
             }
         }
 
@@ -496,7 +496,13 @@ namespace Robust.Client.Input
             return true;
         }
 
-        private void LoadKeyFile(ResPath file, bool userData)
+        /// <summary>
+        /// Loads a keybind file, configuring keybinds.
+        /// </summary>
+        /// <param name="file">File to load from the content package</param>
+        /// <param name="defaultRegistration">Whether or not this is a "default" keybind set. If it is, then it won't override the current configuration, only the defaults.</param>
+        /// <param name="userData">Whether or not to load from the user data directory instead of the content package.</param>
+        public void LoadKeyFile(ResPath file, bool defaultRegistration, bool userData = false)
         {
             TextReader reader;
             if (userData)
@@ -517,16 +523,19 @@ namespace Robust.Client.Input
             {
                 var baseKeyRegs = _serialization.Read<KeyBindingRegistration[]>(BaseKeyRegsNode, notNullableOverride: true);
 
+
                 foreach (var reg in baseKeyRegs)
                 {
+                    var invalid = false;
+
                     if (reg.Type != KeyBindingType.Command && !NetworkBindMap.FunctionExists(reg.Function.FunctionName))
                     {
-                        Logger.ErrorS("input", "Key function in {0} does not exist: '{1}'", file,
+                        Logger.DebugS("input", "Key function in {0} does not exist: '{1}'.", file,
                             reg.Function);
-                        continue;
+                        invalid = true;
                     }
 
-                    if (!userData)
+                    if (defaultRegistration)
                     {
                         _defaultRegistrations.Add(reg);
 
@@ -538,19 +547,24 @@ namespace Robust.Client.Input
                         }
                     }
 
-                    RegisterBinding(reg, markModified: userData);
+                    RegisterBinding(reg, markModified: !defaultRegistration, invalid);
                 }
             }
 
-            if (userData && mapping.TryGet("leaveEmpty", out var node))
+            if (!defaultRegistration && mapping.TryGet("leaveEmpty", out var node))
             {
                 var leaveEmpty = _serialization.Read<BoundKeyFunction[]>(node, notNullableOverride: true);
 
-                if (leaveEmpty.Length > 0)
+                foreach (var bind in leaveEmpty)
                 {
                     // Adding to _modifiedKeyFunctions means that these keybinds won't be loaded from the base file.
                     // Because they've been explicitly cleared.
-                    _modifiedKeyFunctions.UnionWith(leaveEmpty);
+                    _modifiedKeyFunctions.Add(bind);
+
+                    // Adding to bindingsByFunction because if the keybind is not valid(For example if it's from another
+                    // server then we will have problems saving the file)
+                    _bindingsByFunction.GetOrNew(bind);
+
                 }
             }
         }
@@ -578,7 +592,7 @@ namespace Robust.Client.Input
             return binding;
         }
 
-        public IKeyBinding RegisterBinding(in KeyBindingRegistration reg, bool markModified = true)
+        public IKeyBinding RegisterBinding(in KeyBindingRegistration reg, bool markModified = true, bool invalid = false)
         {
             var binding = new KeyBinding(this, reg.Function.FunctionName, reg.Type, reg.BaseKey, reg.CanFocus, reg.CanRepeat,
                 reg.AllowSubCombs, reg.Priority, reg.Mod1, reg.Mod2, reg.Mod3);
@@ -609,7 +623,7 @@ namespace Robust.Client.Input
 
         public void InputModeChanged() => OnInputModeChanged?.Invoke();
 
-        private void RegisterBinding(KeyBinding binding, bool markModified = true)
+        private void RegisterBinding(KeyBinding binding, bool markModified = true, bool invalid = false)
         {
             // we sort larger combos first so they take priority over smaller (single key) combos,
             // so they get processed first in KeyDown and such.
@@ -624,7 +638,8 @@ namespace Robust.Client.Input
                 _modifiedKeyFunctions.Add(binding.Function);
             }
 
-            _bindings.Insert(pos, binding);
+            if (!invalid)
+                _bindings.Insert(pos, binding);
             _bindingsByFunction.GetOrNew(binding.Function).Add(binding);
             OnKeyBindingAdded?.Invoke(binding);
         }

Robust.Client/Placement/PlacementManager.cs

@@ -495,7 +495,7 @@ namespace Robust.Client.Placement
         {
             // Try to get current map.
             var map = MapId.Nullspace;
-            if (EntityManager.TryGetComponent(PlayerManager.LocalPlayer?.ControlledEntity, out TransformComponent? xform))
+            if (EntityManager.TryGetComponent(PlayerManager.LocalEntity, out TransformComponent? xform))
             {
                 map = xform.MapID;
             }
@@ -512,7 +512,7 @@ namespace Robust.Client.Placement
 
         private bool CurrentEraserMouseCoordinates(out EntityCoordinates coordinates)
         {
-            var ent = PlayerManager.LocalPlayer?.ControlledEntity ?? EntityUid.Invalid;
+            var ent = PlayerManager.LocalEntity ?? EntityUid.Invalid;
             if (ent == EntityUid.Invalid)
             {
                 coordinates = new EntityCoordinates();
@@ -640,7 +640,7 @@ namespace Robust.Client.Placement
 
             if (CurrentPermission is not {Range: > 0} ||
                 !CurrentMode.RangeRequired ||
-                PlayerManager.LocalPlayer?.ControlledEntity is not {Valid: true} controlled)
+                PlayerManager.LocalEntity is not {Valid: true} controlled)
                 return;
 
             var worldPos = EntityManager.GetComponent<TransformComponent>(controlled).WorldPosition;

Robust.Client/Placement/PlacementMode.cs

@@ -216,7 +216,7 @@ namespace Robust.Client.Placement
         {
             if (!RangeRequired)
                 return true;
-            var controlled = pManager.PlayerManager.LocalPlayer?.ControlledEntity ?? EntityUid.Invalid;
+            var controlled = pManager.PlayerManager.LocalEntity ?? EntityUid.Invalid;
             if (controlled == EntityUid.Invalid)
             {
                 return false;

Robust.Client/Player/FilterSystem.cs

@@ -10,14 +10,13 @@ namespace Robust.Client.Player
 
         public override Filter FromEntities(Filter filter, params EntityUid[] entities)
         {
-            if (_playerManager.LocalPlayer is not { } localPlayer
-                || localPlayer.Session.AttachedEntity is not {Valid: true} attachedUid)
+            if (_playerManager.LocalEntity is not {Valid: true} attachedUid)
                 return filter;
 
             foreach (var uid in entities)
             {
                 if (uid == attachedUid)
-                    filter.AddPlayer(localPlayer.Session);
+                    filter.AddPlayer(_playerManager.LocalSession!);
             }
 
             return filter;

Robust.Client/Replays/ReplayRecordingManager.cs

@@ -36,12 +36,12 @@ internal sealed class ReplayRecordingManager : SharedReplayRecordingManager
 
     private void OnRecordingStarted(MappingDataNode metadata, List<object> messages)
     {
-        if (_player.LocalPlayer == null)
+        if (_player.LocalSession == null)
             return;
 
         // Add information about the user doing the recording. This is used to set the default replay observer position
         // when playing back the replay.
-        var guid = _player.LocalPlayer.UserId.UserId.ToString();
+        var guid = _player.LocalUser.ToString();
         metadata[ReplayConstants.MetaKeyRecordedBy] = new ValueDataNode(guid);
     }
 

Robust.Client/UserInterface/Control.cs

@@ -545,6 +545,36 @@ namespace Robust.Client.UserInterface
             Draw(renderHandle.DrawingHandleScreen);
         }
 
+        protected internal virtual void PreRenderChildren(ref ControlRenderArguments args)
+        {
+
+        }
+
+        protected internal virtual void PostRenderChildren(ref ControlRenderArguments args)
+        {
+
+        }
+
+        protected internal virtual void RenderChildOverride(ref ControlRenderArguments args, int childIndex, Vector2i position)
+        {
+            RenderControl(ref args, childIndex, position);
+        }
+
+        public ref struct ControlRenderArguments
+        {
+            public IRenderHandle Handle;
+            public ref int Total;
+            public Vector2i Position;
+            public Color Modulate;
+            public UIBox2i? ScissorBox;
+            public ref Matrix3 CoordinateTransform;
+        }
+
+        protected void RenderControl(ref ControlRenderArguments args, int childIndex, Vector2i position)
+        {
+            UserInterfaceManagerInternal.RenderControl(args.Handle, ref args.Total, GetChild(childIndex), position, args.Modulate, args.ScissorBox, args.CoordinateTransform);
+        }
+
         public void UpdateDraw()
         {
         }

Robust.Client/UserInterface/Controls/BaseButton.cs

@@ -1,5 +1,6 @@
 using System;
 using System.Collections.Generic;
+using System.Linq;
 using Robust.Client.Audio;
 using Robust.Client.ResourceManagement;
 using Robust.Shared.ContentPack;
@@ -37,8 +38,10 @@ namespace Robust.Client.UserInterface.Controls
             get => _group;
             set
             {
+                if (value?.InternalButtons.Contains(this) ?? false)
+                    return; // No work to do.
                 // Remove from old group.
-                _group?.Buttons.Remove(this);
+                _group?.InternalButtons.Remove(this);
 
                 _group = value;
 
@@ -47,11 +50,21 @@ namespace Robust.Client.UserInterface.Controls
                     return;
                 }
 
-                value.Buttons.Add(this);
+                value.InternalButtons.Add(this);
                 ToggleMode = true;
 
-                // Set us to pressed if we're the first button.
-                Pressed = value.Buttons.Count == 0;
+                if (value.IsNoneSetAllowed)
+                {
+                    // Still UNPRESS if there's another pressed button, but don't PRESS it otherwise.
+                    if (value.Pressed != this)
+                        _pressed = false;
+                }
+                else
+                {
+                    // Set us to pressed if we're the first button. Doesn't go through the setter to avoid setting off our own error check.
+                    _pressed = value.InternalButtons.Count == 1;
+                }
+                DrawModeChanged();
             }
         }
 
@@ -95,7 +108,7 @@ namespace Robust.Client.UserInterface.Controls
                     return;
                 }
 
-                if (!value && Group != null)
+                if (!value && Group is { IsNoneSetAllowed: false })
                 {
                     throw new InvalidOperationException("Cannot directly unset a grouped button. Set another button in the group instead.");
                 }
@@ -326,7 +339,7 @@ namespace Robust.Client.UserInterface.Controls
                 return;
             }
 
-            foreach (var button in _group.Buttons)
+            foreach (var button in _group.InternalButtons)
             {
                 if (button != this && button.Pressed)
                 {
@@ -440,6 +453,29 @@ namespace Robust.Client.UserInterface.Controls
     /// </remarks>
     public sealed class ButtonGroup
     {
-        internal readonly List<BaseButton> Buttons = new();
+        /// <summary>
+        /// Whether it is legal for this button group to have no selected button.
+        /// </summary>
+        /// <remarks>
+        /// If true, it's legal for no button in the group to be active.
+        /// This is then the initial state of a new group of buttons (no button is automatically selected),
+        /// and it becomes legal to manually clear the active button through code.
+        /// The user cannot manually unselect the active button regardless, only by selecting a difference button.
+        /// </remarks>
+        public bool IsNoneSetAllowed { get; }
+
+        /// <summary>
+        /// Create a new <see cref="ButtonGroup"/>
+        /// </summary>
+        /// <param name="isNoneSetAllowed">The value of <see cref="IsNoneSetAllowed"/> on the new button group.</param>
+        public ButtonGroup(bool isNoneSetAllowed = true)
+        {
+            IsNoneSetAllowed = isNoneSetAllowed;
+        }
+
+        internal readonly List<BaseButton> InternalButtons = new();
+        public IReadOnlyList<BaseButton> Buttons => InternalButtons;
+
+        public BaseButton? Pressed => InternalButtons.FirstOrDefault(x => x.Pressed);
     }
 }

Robust.Client/UserInterface/Controls/OptionButton.cs

@@ -12,6 +12,7 @@ namespace Robust.Client.UserInterface.Controls
     public class OptionButton : ContainerButton
     {
         public const string StyleClassOptionButton = "optionButton";
+        public const string StyleClassPopup = "optionButtonPopup";
         public const string StyleClassOptionTriangle = "optionTriangle";
         public readonly ScrollContainer OptionsScroll;
 
@@ -74,7 +75,8 @@ namespace Robust.Client.UserInterface.Controls
 
             _popup = new Popup()
             {
-                Children = { OptionsScroll }
+                Children = { new PanelContainer(), OptionsScroll },
+                StyleClasses = { StyleClassPopup }
             };
             _popup.OnPopupHide += OnPopupHide;
 
@@ -99,6 +101,11 @@ namespace Robust.Client.UserInterface.Controls
             AddItem(label, id);
         }
 
+        public virtual void ButtonOverride(Button button)
+        {
+
+        }
+
         public void AddItem(string label, int? id = null)
         {
             if (id == null)
@@ -132,6 +139,8 @@ namespace Robust.Client.UserInterface.Controls
             {
                 Select(0);
             }
+
+            ButtonOverride(button);
         }
 
         private void TogglePopup(bool show)
@@ -139,6 +148,8 @@ namespace Robust.Client.UserInterface.Controls
             if (show)
             {
                 var globalPos = GlobalPosition;
+                globalPos.Y += Size.Y + 1; // Place it below us, with a safety margin.
+                globalPos.Y -= Margin.SumVertical;
                 OptionsScroll.Measure(Window?.Size ?? Vector2Helpers.Infinity);
                 var (minX, minY) = OptionsScroll.DesiredSize;
                 var box = UIBox2.FromDimensions(globalPos, new Vector2(Math.Max(minX, Width), minY));

Robust.Client/UserInterface/Controls/PanelContainer.cs

@@ -15,13 +15,13 @@ namespace Robust.Client.UserInterface.Controls
         {
             base.Draw(handle);
 
-            var style = _getStyleBox();
+            var style = GetStyleBox();
             style?.Draw(handle, PixelSizeBox, UIScale);
         }
 
         protected override Vector2 MeasureOverride(Vector2 availableSize)
         {
-            var styleSize = _getStyleBox()?.MinimumSize ?? Vector2.Zero;
+            var styleSize = GetStyleBox()?.MinimumSize ?? Vector2.Zero;
             var measureSize = Vector2.Max(availableSize - styleSize, Vector2.Zero);
             var childSize = Vector2.Zero;
             foreach (var child in Children)
@@ -36,7 +36,7 @@ namespace Robust.Client.UserInterface.Controls
         protected override Vector2 ArrangeOverride(Vector2 finalSize)
         {
             var ourSize = UIBox2.FromDimensions(Vector2.Zero, finalSize);
-            var contentBox = _getStyleBox()?.GetContentBox(ourSize, 1) ?? ourSize;
+            var contentBox = GetStyleBox()?.GetContentBox(ourSize, 1) ?? ourSize;
 
             foreach (var child in Children)
             {
@@ -47,7 +47,7 @@ namespace Robust.Client.UserInterface.Controls
         }
 
         [System.Diagnostics.Contracts.Pure]
-        private StyleBox? _getStyleBox()
+        protected StyleBox? GetStyleBox()
         {
             if (PanelOverride != null)
             {

Robust.Client/UserInterface/Controls/TextureRect.cs

@@ -17,6 +17,9 @@ namespace Robust.Client.UserInterface.Controls
     {
         public const string StylePropertyTexture = "texture";
         public const string StylePropertyShader = "shader";
+        public const string StylePropertyTextureStretch = "texture-stretch";
+        public const string StylePropertyTextureScale = "texture-scale";
+        public const string StylePropertyTextureSizeTarget = "texture-size-target";
 
         private bool _canShrink;
         private Texture? _texture;
@@ -29,7 +32,18 @@ namespace Robust.Client.UserInterface.Controls
         /// </summary>
         public Texture? Texture
         {
-            get => _texture;
+            get
+            {
+                if (_texture is null)
+                {
+                    if (TryGetStyleProperty(StylePropertyTexture, out Texture? texture))
+                    {
+                        return texture;
+                    }
+                }
+
+                return _texture;
+            }
             set
             {
                 var oldSize = _texture?.Size;
@@ -43,6 +57,7 @@ namespace Robust.Client.UserInterface.Controls
         }
 
         private string? _texturePath;
+        private StretchMode _stretch = StretchMode.Keep;
 
         public string TexturePath
         {
@@ -54,21 +69,45 @@ namespace Robust.Client.UserInterface.Controls
 
         }
 
+        protected override void StylePropertiesChanged()
+        {
+            base.StylePropertiesChanged();
+            InvalidateMeasure();
+        }
+
         protected override void OnThemeUpdated()
         {
             if (_texturePath != null) Texture = Theme.ResolveTexture(_texturePath);
             base.OnThemeUpdated();
         }
 
+        public Vector2 TextureSizeTarget
+        {
+            get
+            {
+                if (!TryGetStyleProperty(StylePropertyTextureSizeTarget, out Vector2 target))
+                    target = _textureScale * Texture?.Size ?? Vector2.Zero;
+
+                return target;
+            }
+        }
+
         /// <summary>
         ///     Scales the texture displayed.
         /// </summary>
         /// <remarks>
         ///     This does not apply to the following stretch modes: <see cref="StretchMode.Scale"/>.
+        ///     This additionally does not apply if a size target is set.
         /// </remarks>
         public Vector2 TextureScale
         {
-            get => _textureScale;
+            get
+            {
+                if (!TryGetStyleProperty(StylePropertyTextureScale, out Vector2 scale))
+                    scale = _textureScale;
+
+                return scale;
+            }
             set
             {
                 _textureScale = value;
@@ -96,23 +135,27 @@ namespace Robust.Client.UserInterface.Controls
         /// <summary>
         ///     Controls how the texture should be drawn if the control is larger than the size of the texture.
         /// </summary>
-        public StretchMode Stretch { get; set; } = StretchMode.Keep;
+        public StretchMode Stretch
+        {
+            get
+            {
+                if (!TryGetStyleProperty(StylePropertyTextureStretch, out StretchMode stretch))
+                    stretch = _stretch;
+                return stretch;
+            }
+            set => _stretch = value;
+        }
 
         protected internal override void Draw(DrawingHandleScreen handle)
         {
             base.Draw(handle);
 
-            var texture = _texture;
-            ShaderInstance? shader = null;
+            var texture = Texture;
 
-            if (texture == null)
-            {
-                TryGetStyleProperty(StylePropertyTexture, out texture);
-                if (texture == null)
-                {
-                    return;
-                }
-            }
+            if (texture is null)
+                return;
+
+            ShaderInstance? shader = null;
 
             if (ShaderOverride != null)
             {
@@ -167,17 +210,17 @@ namespace Robust.Client.UserInterface.Controls
                 case StretchMode.Tile:
                 // TODO: Implement Tile.
                 case StretchMode.Keep:
-                    return UIBox2.FromDimensions(Vector2.Zero, texture.Size * _textureScale * UIScale);
+                    return UIBox2.FromDimensions(Vector2.Zero, TextureSizeTarget * UIScale);
                 case StretchMode.KeepCentered:
                 {
-                    var position = (PixelSize - texture.Size * _textureScale * UIScale) / 2;
-                    return UIBox2.FromDimensions(position, texture.Size * _textureScale * UIScale);
+                    var position = (PixelSize - TextureSizeTarget) / 2;
+                    return UIBox2.FromDimensions(position, TextureSizeTarget * UIScale);
                 }
 
                 case StretchMode.KeepAspect:
                 case StretchMode.KeepAspectCentered:
                 {
-                    var (texWidth, texHeight) = texture.Size * _textureScale;
+                    var (texWidth, texHeight) = TextureSizeTarget;
                     var width = texWidth * (PixelSize.Y / texHeight);
                     var height = (float)PixelSize.Y;
                     if (width > PixelSize.X)
@@ -197,7 +240,7 @@ namespace Robust.Client.UserInterface.Controls
                 }
 
                 case StretchMode.KeepAspectCovered:
-                    var texSize = texture.Size * _textureScale;
+                    var texSize = TextureSizeTarget;
                     // Calculate the scale necessary to fit width and height to control size.
                     var (scaleX, scaleY) = PixelSize / texSize;
                     // Use whichever scale is greater.
@@ -259,19 +302,10 @@ namespace Robust.Client.UserInterface.Controls
 
         protected override Vector2 MeasureOverride(Vector2 availableSize)
         {
-            var texture = _texture;
-
-            if (texture == null)
-            {
-                TryGetStyleProperty(StylePropertyTexture, out texture);
-            }
-
-            if (texture == null || CanShrink)
-            {
+            if (CanShrink || Texture == null)
                 return Vector2.Zero;
-            }
 
-            return texture.Size * TextureScale;
+            return TextureSizeTarget;
         }
     }
 }

Robust.Client/UserInterface/IUserInterfaceManagerInternal.cs

@@ -61,6 +61,9 @@ namespace Robust.Client.UserInterface
         Vector2? CalcRelativeMousePositionFor(Control control, ScreenCoordinates mousePos);
 
         Color GetMainClearColor();
+
+        void RenderControl(IRenderHandle renderHandle, ref int total, Control control, Vector2i position, Color modulate,
+            UIBox2i? scissorBox, Matrix3 coordinateTransform);
     }
 }
 

Robust.Client/UserInterface/UserInterfaceManager.Layout.cs

@@ -132,9 +132,10 @@ internal sealed partial class UserInterfaceManager
             try
             {
                 var total = 0;
-                _render(renderHandle, ref total, root, Vector2i.Zero, Color.White, null);
                 var drawingHandle = renderHandle.DrawingHandleScreen;
-                drawingHandle.SetTransform(Vector2.Zero, Angle.Zero, Vector2.One);
+                drawingHandle.SetTransform(Matrix3.Identity);
+                RenderControl(renderHandle, ref total, root, Vector2i.Zero, Color.White, null, Matrix3.Identity);
+                drawingHandle.SetTransform(Matrix3.Identity);
                 OnPostDrawUIRoot?.Invoke(new PostDrawUIRootEventArgs(root, drawingHandle));
 
                 _prof.WriteValue("Controls rendered", ProfData.Int32(total));

Robust.Client/UserInterface/UserInterfaceManager.cs

@@ -75,7 +75,7 @@ namespace Robust.Client.UserInterface
 
                 foreach (var root in _roots)
                 {
-                    if (root.Stylesheet != null)
+                    if (root.Stylesheet == null)
                     {
                         root.StylesheetUpdateRecursive();
                     }
@@ -329,8 +329,8 @@ namespace Robust.Client.UserInterface
             }
         }
 
-        private void _render(IRenderHandle renderHandle, ref int total, Control control, Vector2i position, Color modulate,
-            UIBox2i? scissorBox)
+        public void RenderControl(IRenderHandle renderHandle, ref int total, Control control, Vector2i position, Color modulate,
+            UIBox2i? scissorBox, Matrix3 coordinateTransform)
         {
             if (!control.Visible)
             {
@@ -377,7 +377,10 @@ namespace Robust.Client.UserInterface
             total += 1;
 
             var handle = renderHandle.DrawingHandleScreen;
-            handle.SetTransform(position, Angle.Zero, Vector2.One);
+            var oldXform = handle.GetTransform();
+            var xform = oldXform;
+            xform.Multiply(Matrix3.CreateTransform(position, Angle.Zero, Vector2.One));
+            handle.SetTransform(xform);
             modulate *= control.Modulate;
 
             if (_rendering || control.AlwaysRender)
@@ -389,16 +392,32 @@ namespace Robust.Client.UserInterface
                 handle.Modulate = oldMod;
                 handle.UseShader(null);
             }
+            handle.SetTransform(oldXform);
+            var args = new Control.ControlRenderArguments()
+            {
+                Handle = renderHandle,
+                Total = ref total,
+                Modulate = modulate,
+                ScissorBox = scissorRegion,
+                CoordinateTransform = ref coordinateTransform
+            };
+
+            control.PreRenderChildren(ref args);
 
             foreach (var child in control.Children)
             {
-                _render(renderHandle, ref total, child, position + child.PixelPosition, modulate, scissorRegion);
+                var pos = position + (Vector2i) coordinateTransform.Transform(child.PixelPosition);
+                control.RenderChildOverride(ref args, child.GetPositionInParent(), pos);
             }
 
+            control.PostRenderChildren(ref args);
+
             if (clip)
             {
                 renderHandle.SetScissor(scissorBox);
             }
+
+            handle.SetTransform(oldXform);
         }
 
         public Color GetMainClearColor() => RootControl.ActualBgColor;

Robust.Roslyn.Shared/AttributeHelper.cs

@@ -0,0 +1,46 @@
+using System.Diagnostics.CodeAnalysis;
+using Microsoft.CodeAnalysis;
+
+namespace Robust.Roslyn.Shared;
+
+#nullable enable
+
+public static class AttributeHelper
+{
+    public static bool HasAttribute(ISymbol symbol, string attributeMetadataName, [NotNullWhen(true)] out AttributeData? matchedAttribute)
+    {
+        foreach (var attribute in symbol.GetAttributes())
+        {
+            if (attribute.AttributeClass == null)
+                continue;
+
+            if (TypeSymbolHelper.ShittyTypeMatch(attribute.AttributeClass, attributeMetadataName))
+            {
+                matchedAttribute = attribute;
+                return true;
+            }
+        }
+
+        matchedAttribute = null;
+        return false;
+    }
+
+    public static bool GetNamedArgumentBool(AttributeData data, string name, bool defaultValue)
+    {
+        foreach (var kv in data.NamedArguments)
+        {
+            if (kv.Key != name)
+                continue;
+
+            if (kv.Value.Kind != TypedConstantKind.Primitive)
+                continue;
+
+            if (kv.Value.Value is not bool value)
+                continue;
+
+            return value;
+        }
+
+        return defaultValue;
+    }
+}

Robust.Roslyn.Shared/Diagnostics.cs

@@ -1,6 +1,6 @@
 using Microsoft.CodeAnalysis;
 
-namespace Robust.Analyzers;
+namespace Robust.Roslyn.Shared;
 
 public static class Diagnostics
 {
@@ -24,6 +24,10 @@ public static class Diagnostics
     public const string IdNestedDataDefinitionPartial = "RA0018";
     public const string IdDataFieldWritable = "RA0019";
     public const string IdDataFieldPropertyWritable = "RA0020";
+    public const string IdComponentPauseNotComponent = "RA0021";
+    public const string IdComponentPauseNoFields = "RA0022";
+    public const string IdComponentPauseNoParentAttribute = "RA0023";
+    public const string IdComponentPauseWrongTypeAttribute = "RA0024";
 
     public static SuppressionDescriptor MeansImplicitAssignment =>
         new SuppressionDescriptor("RADC1000", "CS0649", "Marked as implicitly assigned.");

Robust.Roslyn.Shared/Helpers/EquatableArray{T}.cs

@@ -0,0 +1,201 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+// Taken from https://github.com/CommunityToolkit/dotnet/blob/ecd1711b740f4f88d2bb943ce292ae4fc90df1bc/src/CommunityToolkit.Mvvm.SourceGenerators/Helpers/EquatableArray%7BT%7D.cs
+
+using System.Collections;
+using System.Collections.Immutable;
+using System.Diagnostics.CodeAnalysis;
+using System.Runtime.CompilerServices;
+
+namespace Robust.Roslyn.Shared.Helpers;
+
+#nullable enable
+
+/// <summary>
+/// Extensions for <see cref="EquatableArray{T}"/>.
+/// </summary>
+public static class EquatableArray
+{
+    /// <summary>
+    /// Creates an <see cref="EquatableArray{T}"/> instance from a given <see cref="ImmutableArray{T}"/>.
+    /// </summary>
+    /// <typeparam name="T">The type of items in the input array.</typeparam>
+    /// <param name="array">The input <see cref="ImmutableArray{T}"/> instance.</param>
+    /// <returns>An <see cref="EquatableArray{T}"/> instance from a given <see cref="ImmutableArray{T}"/>.</returns>
+    public static EquatableArray<T> AsEquatableArray<T>(this ImmutableArray<T> array)
+        where T : IEquatable<T>
+    {
+        return new(array);
+    }
+}
+
+/// <summary>
+/// An immutable, equatable array. This is equivalent to <see cref="ImmutableArray{T}"/> but with value equality support.
+/// </summary>
+/// <typeparam name="T">The type of values in the array.</typeparam>
+public readonly struct EquatableArray<T> : IEquatable<EquatableArray<T>>, IEnumerable<T>
+    where T : IEquatable<T>
+{
+    /// <summary>
+    /// The underlying <typeparamref name="T"/> array.
+    /// </summary>
+    private readonly T[]? array;
+
+    /// <summary>
+    /// Creates a new <see cref="EquatableArray{T}"/> instance.
+    /// </summary>
+    /// <param name="array">The input <see cref="ImmutableArray{T}"/> to wrap.</param>
+    public EquatableArray(ImmutableArray<T> array)
+    {
+        this.array = Unsafe.As<ImmutableArray<T>, T[]?>(ref array);
+    }
+
+    /// <summary>
+    /// Gets a reference to an item at a specified position within the array.
+    /// </summary>
+    /// <param name="index">The index of the item to retrieve a reference to.</param>
+    /// <returns>A reference to an item at a specified position within the array.</returns>
+    public ref readonly T this[int index]
+    {
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        get => ref AsImmutableArray().ItemRef(index);
+    }
+
+    /// <summary>
+    /// Gets a value indicating whether the current array is empty.
+    /// </summary>
+    public bool IsEmpty
+    {
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        get => AsImmutableArray().IsEmpty;
+    }
+
+    /// <sinheritdoc/>
+    public bool Equals(EquatableArray<T> array)
+    {
+        return AsSpan().SequenceEqual(array.AsSpan());
+    }
+
+    /// <sinheritdoc/>
+    public override bool Equals([NotNullWhen(true)] object? obj)
+    {
+        return obj is EquatableArray<T> array && Equals(this, array);
+    }
+
+    /// <sinheritdoc/>
+    public override int GetHashCode()
+    {
+        if (this.array is not T[] array)
+        {
+            return 0;
+        }
+
+        HashCode hashCode = default;
+
+        foreach (T item in array)
+        {
+            hashCode.Add(item);
+        }
+
+        return hashCode.ToHashCode();
+    }
+
+    /// <summary>
+    /// Gets an <see cref="ImmutableArray{T}"/> instance from the current <see cref="EquatableArray{T}"/>.
+    /// </summary>
+    /// <returns>The <see cref="ImmutableArray{T}"/> from the current <see cref="EquatableArray{T}"/>.</returns>
+    [MethodImpl(MethodImplOptions.AggressiveInlining)]
+    public ImmutableArray<T> AsImmutableArray()
+    {
+        return Unsafe.As<T[]?, ImmutableArray<T>>(ref Unsafe.AsRef(in this.array));
+    }
+
+    /// <summary>
+    /// Creates an <see cref="EquatableArray{T}"/> instance from a given <see cref="ImmutableArray{T}"/>.
+    /// </summary>
+    /// <param name="array">The input <see cref="ImmutableArray{T}"/> instance.</param>
+    /// <returns>An <see cref="EquatableArray{T}"/> instance from a given <see cref="ImmutableArray{T}"/>.</returns>
+    public static EquatableArray<T> FromImmutableArray(ImmutableArray<T> array)
+    {
+        return new(array);
+    }
+
+    /// <summary>
+    /// Returns a <see cref="ReadOnlySpan{T}"/> wrapping the current items.
+    /// </summary>
+    /// <returns>A <see cref="ReadOnlySpan{T}"/> wrapping the current items.</returns>
+    public ReadOnlySpan<T> AsSpan()
+    {
+        return AsImmutableArray().AsSpan();
+    }
+
+    /// <summary>
+    /// Copies the contents of this <see cref="EquatableArray{T}"/> instance to a mutable array.
+    /// </summary>
+    /// <returns>The newly instantiated array.</returns>
+    public T[] ToArray()
+    {
+        return AsImmutableArray().ToArray();
+    }
+
+    /// <summary>
+    /// Gets an <see cref="ImmutableArray{T}.Enumerator"/> value to traverse items in the current array.
+    /// </summary>
+    /// <returns>An <see cref="ImmutableArray{T}.Enumerator"/> value to traverse items in the current array.</returns>
+    public ImmutableArray<T>.Enumerator GetEnumerator()
+    {
+        return AsImmutableArray().GetEnumerator();
+    }
+
+    /// <sinheritdoc/>
+    IEnumerator<T> IEnumerable<T>.GetEnumerator()
+    {
+        return ((IEnumerable<T>)AsImmutableArray()).GetEnumerator();
+    }
+
+    /// <sinheritdoc/>
+    IEnumerator IEnumerable.GetEnumerator()
+    {
+        return ((IEnumerable)AsImmutableArray()).GetEnumerator();
+    }
+
+    /// <summary>
+    /// Implicitly converts an <see cref="ImmutableArray{T}"/> to <see cref="EquatableArray{T}"/>.
+    /// </summary>
+    /// <returns>An <see cref="EquatableArray{T}"/> instance from a given <see cref="ImmutableArray{T}"/>.</returns>
+    public static implicit operator EquatableArray<T>(ImmutableArray<T> array)
+    {
+        return FromImmutableArray(array);
+    }
+
+    /// <summary>
+    /// Implicitly converts an <see cref="EquatableArray{T}"/> to <see cref="ImmutableArray{T}"/>.
+    /// </summary>
+    /// <returns>An <see cref="ImmutableArray{T}"/> instance from a given <see cref="EquatableArray{T}"/>.</returns>
+    public static implicit operator ImmutableArray<T>(EquatableArray<T> array)
+    {
+        return array.AsImmutableArray();
+    }
+
+    /// <summary>
+    /// Checks whether two <see cref="EquatableArray{T}"/> values are the same.
+    /// </summary>
+    /// <param name="left">The first <see cref="EquatableArray{T}"/> value.</param>
+    /// <param name="right">The second <see cref="EquatableArray{T}"/> value.</param>
+    /// <returns>Whether <paramref name="left"/> and <paramref name="right"/> are equal.</returns>
+    public static bool operator ==(EquatableArray<T> left, EquatableArray<T> right)
+    {
+        return left.Equals(right);
+    }
+
+    /// <summary>
+    /// Checks whether two <see cref="EquatableArray{T}"/> values are not the same.
+    /// </summary>
+    /// <param name="left">The first <see cref="EquatableArray{T}"/> value.</param>
+    /// <param name="right">The second <see cref="EquatableArray{T}"/> value.</param>
+    /// <returns>Whether <paramref name="left"/> and <paramref name="right"/> are not equal.</returns>
+    public static bool operator !=(EquatableArray<T> left, EquatableArray<T> right)
+    {
+        return !left.Equals(right);
+    }
+}

Robust.Roslyn.Shared/Helpers/HashCode.cs

@@ -0,0 +1,190 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+// Taken from https://raw.githubusercontent.com/CommunityToolkit/dotnet/ecd1711b740f4f88d2bb943ce292ae4fc90df1bc/src/CommunityToolkit.Mvvm.SourceGenerators/Helpers/HashCode.cs
+
+using System.ComponentModel;
+using System.Runtime.CompilerServices;
+using System.Security.Cryptography;
+
+#pragma warning disable CS0809
+
+namespace System;
+
+#nullable enable
+
+/// <summary>
+/// A polyfill type that mirrors some methods from <see cref="HashCode"/> on .NET 6.
+/// </summary>
+public struct HashCode
+{
+    private const uint Prime1 = 2654435761U;
+    private const uint Prime2 = 2246822519U;
+    private const uint Prime3 = 3266489917U;
+    private const uint Prime4 = 668265263U;
+    private const uint Prime5 = 374761393U;
+
+    private static readonly uint seed = GenerateGlobalSeed();
+
+    private uint v1, v2, v3, v4;
+    private uint queue1, queue2, queue3;
+    private uint length;
+
+    /// <summary>
+    /// Initializes the default seed.
+    /// </summary>
+    /// <returns>A random seed.</returns>
+    private static unsafe uint GenerateGlobalSeed()
+    {
+        byte[] bytes = new byte[4];
+
+        using (RandomNumberGenerator generator = RandomNumberGenerator.Create())
+        {
+            generator.GetBytes(bytes);
+        }
+
+        return BitConverter.ToUInt32(bytes, 0);
+    }
+
+    /// <summary>
+    /// Adds a single value to the current hash.
+    /// </summary>
+    /// <typeparam name="T">The type of the value to add into the hash code.</typeparam>
+    /// <param name="value">The value to add into the hash code.</param>
+    public void Add<T>(T value)
+    {
+        Add(value?.GetHashCode() ?? 0);
+    }
+
+    [MethodImpl(MethodImplOptions.AggressiveInlining)]
+    private static void Initialize(out uint v1, out uint v2, out uint v3, out uint v4)
+    {
+        v1 = seed + Prime1 + Prime2;
+        v2 = seed + Prime2;
+        v3 = seed;
+        v4 = seed - Prime1;
+    }
+
+    [MethodImpl(MethodImplOptions.AggressiveInlining)]
+    private static uint Round(uint hash, uint input)
+    {
+        return RotateLeft(hash + input * Prime2, 13) * Prime1;
+    }
+
+    [MethodImpl(MethodImplOptions.AggressiveInlining)]
+    private static uint QueueRound(uint hash, uint queuedValue)
+    {
+        return RotateLeft(hash + queuedValue * Prime3, 17) * Prime4;
+    }
+
+    [MethodImpl(MethodImplOptions.AggressiveInlining)]
+    private static uint MixState(uint v1, uint v2, uint v3, uint v4)
+    {
+        return RotateLeft(v1, 1) + RotateLeft(v2, 7) + RotateLeft(v3, 12) + RotateLeft(v4, 18);
+    }
+
+    [MethodImpl(MethodImplOptions.AggressiveInlining)]
+    private static uint MixEmptyState()
+    {
+        return seed + Prime5;
+    }
+
+    [MethodImpl(MethodImplOptions.AggressiveInlining)]
+    private static uint MixFinal(uint hash)
+    {
+        hash ^= hash >> 15;
+        hash *= Prime2;
+        hash ^= hash >> 13;
+        hash *= Prime3;
+        hash ^= hash >> 16;
+
+        return hash;
+    }
+
+    private void Add(int value)
+    {
+        uint val = (uint)value;
+        uint previousLength = this.length++;
+        uint position = previousLength % 4;
+
+        if (position == 0)
+        {
+            this.queue1 = val;
+        }
+        else if (position == 1)
+        {
+            this.queue2 = val;
+        }
+        else if (position == 2)
+        {
+            this.queue3 = val;
+        }
+        else
+        {
+            if (previousLength == 3)
+            {
+                Initialize(out this.v1, out this.v2, out this.v3, out this.v4);
+            }
+
+            this.v1 = Round(this.v1, this.queue1);
+            this.v2 = Round(this.v2, this.queue2);
+            this.v3 = Round(this.v3, this.queue3);
+            this.v4 = Round(this.v4, val);
+        }
+    }
+
+    /// <summary>
+    /// Gets the resulting hashcode from the current instance.
+    /// </summary>
+    /// <returns>The resulting hashcode from the current instance.</returns>
+    public int ToHashCode()
+    {
+        uint length = this.length;
+        uint position = length % 4;
+        uint hash = length < 4 ? MixEmptyState() : MixState(this.v1, this.v2, this.v3, this.v4);
+
+        hash += length * 4;
+
+        if (position > 0)
+        {
+            hash = QueueRound(hash, this.queue1);
+
+            if (position > 1)
+            {
+                hash = QueueRound(hash, this.queue2);
+
+                if (position > 2)
+                {
+                    hash = QueueRound(hash, this.queue3);
+                }
+            }
+        }
+
+        hash = MixFinal(hash);
+
+        return (int)hash;
+    }
+
+    /// <inheritdoc/>
+    [Obsolete("HashCode is a mutable struct and should not be compared with other HashCodes. Use ToHashCode to retrieve the computed hash code.", error: true)]
+    [EditorBrowsable(EditorBrowsableState.Never)]
+    public override int GetHashCode() => throw new NotSupportedException();
+
+    /// <inheritdoc/>
+    [Obsolete("HashCode is a mutable struct and should not be compared with other HashCodes.", error: true)]
+    [EditorBrowsable(EditorBrowsableState.Never)]
+    public override bool Equals(object? obj) => throw new NotSupportedException();
+
+    /// <summary>
+    /// Rotates the specified value left by the specified number of bits.
+    /// Similar in behavior to the x86 instruction ROL.
+    /// </summary>
+    /// <param name="value">The value to rotate.</param>
+    /// <param name="offset">The number of bits to rotate by.
+    /// Any value outside the range [0..31] is treated as congruent mod 32.</param>
+    /// <returns>The rotated value.</returns>
+    [MethodImpl(MethodImplOptions.AggressiveInlining)]
+    private static uint RotateLeft(uint value, int offset)
+    {
+        return (value << offset) | (value >> (32 - offset));
+    }
+}

Robust.Roslyn.Shared/PartialTypeHelper.cs

@@ -0,0 +1,121 @@
+using System.Collections.Immutable;
+using System.Text;
+using Microsoft.CodeAnalysis;
+using Microsoft.CodeAnalysis.CSharp;
+using Microsoft.CodeAnalysis.CSharp.Syntax;
+using Robust.Roslyn.Shared.Helpers;
+
+namespace Robust.Roslyn.Shared;
+
+#nullable enable
+
+/// <summary>
+/// All the information to make a partial type alternative for a type.
+/// </summary>
+public sealed record PartialTypeInfo(
+    string? Namespace,
+    string Name,
+    string DisplayName,
+    EquatableArray<string> TypeParameterNames,
+    bool IsValid,
+    Location SyntaxLocation,
+    Accessibility Accessibility,
+    TypeKind Kind,
+    bool IsRecord,
+    bool IsAbstract)
+{
+    public static PartialTypeInfo FromSymbol(INamedTypeSymbol symbol, TypeDeclarationSyntax syntax)
+    {
+        var typeParameters = ImmutableArray<string>.Empty;
+        if (symbol.TypeParameters.Length > 0)
+        {
+            var builder = ImmutableArray.CreateBuilder<string>(symbol.TypeParameters.Length);
+            foreach (var typeParameter in symbol.TypeParameters)
+            {
+                builder.Add(typeParameter.Name);
+            }
+
+            typeParameters = builder.MoveToImmutable();
+        }
+
+        return new PartialTypeInfo(
+            symbol.ContainingNamespace.IsGlobalNamespace ? null : symbol.ContainingNamespace.ToDisplayString(),
+            symbol.Name,
+            symbol.ToDisplayString(),
+            typeParameters,
+            syntax.Modifiers.Any(x => x.IsKind(SyntaxKind.PartialKeyword)),
+            syntax.Keyword.GetLocation(),
+            symbol.DeclaredAccessibility,
+            symbol.TypeKind,
+            symbol.IsRecord,
+            symbol.IsAbstract);
+    }
+
+    public bool CheckPartialDiagnostic(SourceProductionContext context, DiagnosticDescriptor diagnostic)
+    {
+        if (!IsValid)
+        {
+            context.ReportDiagnostic(Diagnostic.Create(diagnostic, SyntaxLocation, DisplayName));
+            return true;
+        }
+
+        return false;
+    }
+
+    public string GetGeneratedFileName()
+    {
+        var name = Namespace == null ? Name : $"{Namespace}.{Name}";
+        if (TypeParameterNames.AsImmutableArray().Length > 0)
+            name += $"`{TypeParameterNames.AsImmutableArray().Length}";
+
+        name += ".g.cs";
+
+        return name;
+    }
+
+    public void WriteHeader(StringBuilder builder)
+    {
+        if (Namespace != null)
+            builder.AppendLine($"namespace {Namespace};\n");
+
+        // TODO: Nested classes
+
+        var access = Accessibility switch
+        {
+            Accessibility.Private => "private",
+            Accessibility.ProtectedAndInternal => "private protected",
+            Accessibility.ProtectedOrInternal => "protected internal",
+            Accessibility.Protected => "protected",
+            Accessibility.Internal => "internal",
+            _ => "public"
+        };
+
+        string keyword;
+        if (Kind == TypeKind.Interface)
+        {
+            keyword = "interface";
+        }
+        else
+        {
+            if (IsRecord)
+            {
+                keyword = Kind == TypeKind.Struct ? "record struct" : "record";
+            }
+            else
+            {
+                keyword = Kind == TypeKind.Struct ? "struct" : "class";
+            }
+        }
+
+        builder.Append($"{access} {(IsAbstract ? "abstract " : "")}partial {keyword} {Name}");
+        if (TypeParameterNames.AsSpan().Length > 0)
+        {
+            builder.Append($"<{string.Join(", ", TypeParameterNames.AsImmutableArray())}>");
+        }
+    }
+
+    public void WriteFooter(StringBuilder builder)
+    {
+        // TODO: Nested classes
+    }
+}

Robust.Roslyn.Shared/Robust.Roslyn.Shared.props

@@ -0,0 +1,38 @@
+<Project>
+  <!--
+  I wanted to make a Robust.Roslyn.Shared library project,
+  but doing that causes various random library load failures in practice.
+
+  Instead, you'll get this vomit. Enjoy.
+  -->
+  <PropertyGroup>
+    <TargetFramework>netstandard2.0</TargetFramework>
+    <LangVersion>12</LangVersion>
+    <Nullable>enable</Nullable>
+    <ManagePackageVersionsCentrally>true</ManagePackageVersionsCentrally>
+    <EnforceExtendedAnalyzerRules>true</EnforceExtendedAnalyzerRules>
+    <AllowUnsafeBlocks>true</AllowUnsafeBlocks>
+    <ImplicitUsings>enable</ImplicitUsings>
+    <PolySharpIncludeGeneratedTypes>System.Index;System.Diagnostics.CodeAnalysis.NotNullWhenAttribute;System.Runtime.CompilerServices.IsExternalInit;System.Diagnostics.CodeAnalysis.DoesNotReturnAttribute</PolySharpIncludeGeneratedTypes>
+    <NoWarn>RS2008</NoWarn>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <PackageReference Include="Microsoft.CodeAnalysis.Common" PrivateAssets="all" />
+    <PackageReference Include="Microsoft.CodeAnalysis.CSharp" PrivateAssets="all" />
+    <PackageReference Include="Microsoft.CodeAnalysis.Analyzers" PrivateAssets="all" />
+    <PackageReference Include="Microsoft.CodeAnalysis.Workspaces.Common" />
+
+    <PackageReference Include="PolySharp">
+      <PrivateAssets>all</PrivateAssets>
+      <IncludeAssets>runtime; build; native; contentfiles; analyzers</IncludeAssets>
+    </PackageReference>
+  </ItemGroup>
+
+  <ItemGroup>
+    <Compile Include="..\Robust.Roslyn.Shared\**\*.cs">
+      <Link>Robust.Roslyn.Shared\%(RecursiveDir)%(Filename)%(Extension)</Link>
+    </Compile>
+    <Compile Remove="..\Robust.Roslyn.Shared\obj\**\*.cs" />
+  </ItemGroup>
+</Project>

Robust.Roslyn.Shared/TypeSymbolHelper.cs

@@ -0,0 +1,28 @@
+using Microsoft.CodeAnalysis;
+
+namespace Robust.Roslyn.Shared;
+
+#nullable enable
+
+public static class TypeSymbolHelper
+{
+    public static bool ShittyTypeMatch(INamedTypeSymbol type, string attributeMetadataName)
+    {
+        // Doing it like this only allocates when the type actually matches, which is good enough for me right now.
+        if (!attributeMetadataName.EndsWith(type.Name))
+            return false;
+
+        return type.ToDisplayString() == attributeMetadataName;
+    }
+
+    public static bool ImplementsInterface(INamedTypeSymbol type, string interfaceTypeName)
+    {
+        foreach (var interfaceType in type.AllInterfaces)
+        {
+            if (ShittyTypeMatch(interfaceType, interfaceTypeName))
+                return true;
+        }
+
+        return false;
+    }
+}

Robust.Serialization.Generator/ComponentPauseGenerator.cs

@@ -0,0 +1,252 @@
+using System.Collections.Immutable;
+using System.Text;
+using Microsoft.CodeAnalysis;
+using Microsoft.CodeAnalysis.CSharp.Syntax;
+using Robust.Roslyn.Shared;
+using Robust.Roslyn.Shared.Helpers;
+
+namespace Robust.Serialization.Generator;
+
+/// <summary>
+/// Automatically generates implementations for handling timer unpausing.
+/// </summary>
+[Generator(LanguageNames.CSharp)]
+public sealed class ComponentPauseGenerator : IIncrementalGenerator
+{
+    private const string AutoGenerateComponentPauseAttributeName = "Robust.Shared.Analyzers.AutoGenerateComponentPauseAttribute";
+    private const string AutoPausedFieldAttributeName = "Robust.Shared.Analyzers.AutoPausedFieldAttribute";
+    private const string AutoNetworkFieldAttributeName = "Robust.Shared.Analyzers.AutoNetworkedFieldAttribute";
+    // ReSharper disable once InconsistentNaming
+    private const string IComponentTypeName = "Robust.Shared.GameObjects.IComponent";
+
+    private static readonly DiagnosticDescriptor NotComponentDiagnostic = new(
+        Diagnostics.IdComponentPauseNotComponent,
+        "Class must be an IComponent to use AutoGenerateComponentPause",
+        "Class '{0}' must implement IComponent to be used with [AutoGenerateComponentPause]",
+        "Usage",
+        DiagnosticSeverity.Error,
+        true);
+
+    private static readonly DiagnosticDescriptor NoFieldsDiagnostic = new(
+        Diagnostics.IdComponentPauseNoFields,
+        "AutoGenerateComponentPause has no fields",
+        "Class '{0}' has [AutoGenerateComponentPause] but has no fields or properties with [AutoPausedField]",
+        "Usage",
+        DiagnosticSeverity.Warning,
+        true);
+
+    private static readonly DiagnosticDescriptor NoParentAttributeDiagnostic = new(
+        Diagnostics.IdComponentPauseNoParentAttribute,
+        "AutoPausedField on type of field without AutoGenerateComponentPause",
+        "Field '{0}' has [AutoPausedField] but its containing type does not have [AutoGenerateComponentPause]",
+        "Usage",
+        DiagnosticSeverity.Error,
+        true);
+
+    private static readonly DiagnosticDescriptor WrongTypeAttributeDiagnostic = new(
+        Diagnostics.IdComponentPauseWrongTypeAttribute,
+        "AutoPausedField has wrong type",
+        "Field '{0}' has [AutoPausedField] but is not of type TimeSpan",
+        "Usage",
+        DiagnosticSeverity.Error,
+        true);
+
+    public void Initialize(IncrementalGeneratorInitializationContext context)
+    {
+        var componentInfos = context.SyntaxProvider.ForAttributeWithMetadataName(
+            AutoGenerateComponentPauseAttributeName,
+            (syntaxNode, _) => syntaxNode is TypeDeclarationSyntax,
+            (syntaxContext, _) =>
+            {
+                var symbol = (INamedTypeSymbol)syntaxContext.TargetSymbol;
+
+                var typeDeclarationSyntax = (TypeDeclarationSyntax) syntaxContext.TargetNode;
+                var partialTypeInfo = PartialTypeInfo.FromSymbol(
+                    symbol,
+                    typeDeclarationSyntax);
+
+                var dirty = AttributeHelper.GetNamedArgumentBool(syntaxContext.Attributes[0], "Dirty", false);
+
+                var fieldBuilder = ImmutableArray.CreateBuilder<FieldInfo>();
+                foreach (var member in symbol.GetMembers())
+                {
+                    if (!AttributeHelper.HasAttribute(member, AutoPausedFieldAttributeName, out var _))
+                        continue;
+
+                    var type = member switch
+                    {
+                        IPropertySymbol property => property.Type,
+                        IFieldSymbol field => field.Type,
+                        _ => null
+                    };
+
+                    if (type is not INamedTypeSymbol namedType)
+                        continue;
+
+                    var invalid = false;
+                    var nullable = false;
+                    if (namedType.Name != "TimeSpan")
+                    {
+                        if (namedType is { Name: "Nullable", TypeArguments: [{Name: "TimeSpan"}] })
+                        {
+                            nullable = true;
+                        }
+                        else
+                        {
+                            invalid = true;
+                        }
+                    }
+
+                    // If any pause field has [AutoNetworkedField], automatically mark it to dirty on unpause.
+                    if (AttributeHelper.HasAttribute(member, AutoNetworkFieldAttributeName, out var _))
+                        dirty = true;
+
+                    fieldBuilder.Add(new FieldInfo(member.Name, nullable, invalid, member.Locations[0]));
+                }
+
+                return new ComponentInfo(
+                    partialTypeInfo,
+                    EquatableArray<FieldInfo>.FromImmutableArray(fieldBuilder.ToImmutable()),
+                    dirty,
+                    !TypeSymbolHelper.ImplementsInterface(symbol, IComponentTypeName),
+                    typeDeclarationSyntax.Identifier.GetLocation());
+            });
+
+        context.RegisterImplementationSourceOutput(componentInfos, static (productionContext, info) =>
+        {
+            if (info.NotComponent)
+            {
+                productionContext.ReportDiagnostic(Diagnostic.Create(
+                    NotComponentDiagnostic,
+                    info.Location,
+                    info.PartialTypeInfo.Name));
+                return;
+            }
+
+            // Component always have to be partial anyways due to the serialization generator.
+            // So I can't be arsed to define a diagnostic for this.
+            if (!info.PartialTypeInfo.IsValid)
+                return;
+
+            if (info.Fields.AsImmutableArray().Length == 0)
+            {
+                productionContext.ReportDiagnostic(Diagnostic.Create(
+                    NoFieldsDiagnostic,
+                    info.Location,
+                    info.PartialTypeInfo.Name));
+                return;
+            }
+
+            var builder = new StringBuilder();
+
+            builder.AppendLine("""
+                // <auto-generated />
+
+                using Robust.Shared.GameObjects;
+
+                """);
+
+            info.PartialTypeInfo.WriteHeader(builder);
+
+            builder.AppendLine();
+            builder.AppendLine("{");
+
+            builder.AppendLine($$"""
+                [RobustAutoGenerated]
+                public sealed class {{info.PartialTypeInfo.Name}}_AutoPauseSystem : EntitySystem
+                {
+                    public override void Initialize()
+                    {
+                        SubscribeLocalEvent<{{info.PartialTypeInfo.Name}}, EntityUnpausedEvent>(OnEntityUnpaused);
+                    }
+
+                    private void OnEntityUnpaused(EntityUid uid, {{info.PartialTypeInfo.Name}} component, ref EntityUnpausedEvent args)
+                    {
+                """);
+
+            var anyValidField = false;
+            foreach (var field in info.Fields)
+            {
+                if (field.Invalid)
+                {
+                    productionContext.ReportDiagnostic(Diagnostic.Create(WrongTypeAttributeDiagnostic, field.Location));
+                    continue;
+                }
+
+                if (field.Nullable)
+                {
+                    builder.AppendLine($"""
+                                if (component.{field.Name}.HasValue)
+                                    component.{field.Name} = component.{field.Name}.Value + args.PausedTime;
+                        """);
+                }
+                else
+                {
+                    builder.AppendLine($"        component.{field.Name} += args.PausedTime;");
+                }
+
+                anyValidField = true;
+            }
+
+            if (!anyValidField)
+                return;
+
+            if (info.Dirty)
+                builder.AppendLine("        Dirty(uid, component);");
+
+            builder.AppendLine("""
+                    }
+                }
+                """);
+
+            builder.AppendLine("}");
+
+            info.PartialTypeInfo.WriteFooter(builder);
+
+            productionContext.AddSource(info.PartialTypeInfo.GetGeneratedFileName(), builder.ToString());
+        });
+
+        // Code to report diagnostic for fields that have it but don't have the attribute on the parent.
+        var allFields = context.SyntaxProvider.ForAttributeWithMetadataName(
+            AutoPausedFieldAttributeName,
+            (syntaxNode, _) => syntaxNode is VariableDeclaratorSyntax or PropertyDeclarationSyntax,
+            (syntaxContext, _) =>
+            {
+                var errorTarget = syntaxContext.TargetNode is PropertyDeclarationSyntax prop
+                    ? prop.Identifier.GetLocation()
+                    : syntaxContext.TargetNode.GetLocation();
+                return new AllFieldInfo(
+                    syntaxContext.TargetSymbol.Name,
+                    syntaxContext.TargetSymbol.ContainingType.ToDisplayString(),
+                    errorTarget);
+            });
+
+        var allComponentsTogether = componentInfos.Collect();
+        var allFieldsTogether = allFields.Collect();
+        var componentFieldJoin = allFieldsTogether.Combine(allComponentsTogether);
+
+        context.RegisterImplementationSourceOutput(componentFieldJoin, (productionContext, info) =>
+        {
+            var componentsByName = new HashSet<string>(info.Right.Select(x => x.PartialTypeInfo.DisplayName));
+            foreach (var field in info.Left)
+            {
+                if (!componentsByName.Contains(field.ParentDisplayName))
+                {
+                    productionContext.ReportDiagnostic(
+                        Diagnostic.Create(NoParentAttributeDiagnostic, field.Location, field.Name));
+                }
+            }
+        });
+    }
+
+    public sealed record ComponentInfo(
+        PartialTypeInfo PartialTypeInfo,
+        EquatableArray<FieldInfo> Fields,
+        bool Dirty,
+        bool NotComponent,
+        Location Location);
+
+    public sealed record FieldInfo(string Name, bool Nullable, bool Invalid, Location Location);
+
+    public sealed record AllFieldInfo(string Name, string ParentDisplayName, Location Location);
+}

Robust.Serialization.Generator/Properties/launchSettings.json

@@ -0,0 +1,9 @@
+{
+    "$schema": "http://json.schemastore.org/launchsettings.json",
+    "profiles": {
+        "Generators": {
+            "commandName": "DebugRoslynComponent",
+            "targetProject": "../../Content.Shared/Content.Shared.csproj"
+        }
+    }
+}

Robust.Serialization.Generator/Robust.Serialization.Generator.csproj

@@ -1,16 +1,5 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
-  <PropertyGroup>
-    <TargetFramework>netstandard2.0</TargetFramework>
-    <LangVersion>11</LangVersion>
-    <Nullable>enable</Nullable>
-    <ManagePackageVersionsCentrally>true</ManagePackageVersionsCentrally>
-  </PropertyGroup>
-
-  <ItemGroup>
-    <PackageReference Include="Microsoft.CodeAnalysis.Common" PrivateAssets="all" />
-    <PackageReference Include="Microsoft.CodeAnalysis.CSharp" PrivateAssets="all" />
-    <PackageReference Include="Microsoft.CodeAnalysis.Workspaces.Common" />
-  </ItemGroup>
+  <Import Project="../Robust.Roslyn.Shared/Robust.Roslyn.Shared.props" />
 
 </Project>

Robust.Server/Console/ServerConsoleHost.cs

@@ -2,6 +2,7 @@ using System;
 using System.Collections;
 using System.Collections.Generic;
 using System.Linq;
+using System.Threading;
 using System.Threading.Tasks;
 using Robust.Server.Player;
 using Robust.Shared.Console;
@@ -283,25 +284,25 @@ namespace Robust.Server.Console
         /// Get completions. Non-null results imply that the command was handled. If it is empty, it implies that
         /// there are no completions for this command.
         /// </summary>
-        private ValueTask<CompletionResult?> CalcCompletions(IConsoleShell shell, string[] args, string argStr)
+        private async ValueTask<CompletionResult?> CalcCompletions(IConsoleShell shell, string[] args, string argStr)
         {
             // Logger.Debug(string.Join(", ", args));
 
             if (args.Length <= 1)
             {
                 // Typing out command name, handle this ourselves.
-                return ValueTask.FromResult<CompletionResult?>(CompletionResult.FromOptions(
-                    AvailableCommands.Values.Where(c => ShellCanExecute(shell, c.Command)).Select(c => new CompletionOption(c.Command, c.Description))));
+                return CompletionResult.FromOptions(
+                    AvailableCommands.Values.Where(c => ShellCanExecute(shell, c.Command)).Select(c => new CompletionOption(c.Command, c.Description)));
             }
 
             var cmdName = args[0];
             if (!RegisteredCommands.TryGetValue(cmdName, out var cmd))
-                return ValueTask.FromResult<CompletionResult?>(null);
+                return null;
 
             if (!ShellCanExecute(shell, cmdName))
-                return ValueTask.FromResult<CompletionResult?>(CompletionResult.Empty);
+                return CompletionResult.Empty;
 
-            return ValueTask.FromResult<CompletionResult?>(cmd.GetCompletion(shell, args[1..]));
+            return await cmd.GetCompletionAsync(shell, args[1..], argStr, CancellationToken.None);
         }
 
         private sealed class SudoShell : IConsoleShell

Robust.Server/GameObjects/EntitySystems/MapSystem.cs

@@ -28,7 +28,7 @@ namespace Robust.Server.GameObjects
             base.Initialize();
             SubscribeLocalEvent<MapGridComponent, EmptyGridEvent>(HandleGridEmpty);
 
-            _cfg.OnValueChanged(CVars.GameDeleteEmptyGrids, SetGridDeletion, true);
+            Subs.CVar(_cfg, CVars.GameDeleteEmptyGrids, SetGridDeletion, true);
         }
 
         protected override void OnMapAdd(EntityUid uid, MapComponent component, ComponentAdd args)
@@ -64,13 +64,6 @@ namespace Robust.Server.GameObjects
             return !(grid.GetAllTiles().Any());
         }
 
-        public override void Shutdown()
-        {
-            base.Shutdown();
-
-            _cfg.UnsubValueChanged(CVars.GameDeleteEmptyGrids, SetGridDeletion);
-        }
-
         private void HandleGridEmpty(EntityUid uid, MapGridComponent component, EmptyGridEvent args)
         {
             if (!_deleteEmptyGrids || TerminatingOrDeleted(uid) || HasComp<MapComponent>(uid))

Robust.Server/GameObjects/EntitySystems/PhysicsSystem.cs

@@ -20,7 +20,8 @@ namespace Robust.Server.GameObjects
         {
             base.Initialize();
             LoadMetricCVar();
-            _configurationManager.OnValueChanged(CVars.MetricsEnabled, _ => LoadMetricCVar());
+
+            Subs.CVar(_configurationManager, CVars.MetricsEnabled, _ => LoadMetricCVar());
         }
 
         private void LoadMetricCVar()

Robust.Server/GameStates/ChunkIndicesEnumerator.cs

@@ -1,46 +0,0 @@
-using System.Diagnostics.CodeAnalysis;
-using System.Numerics;
-using Robust.Shared.Maths;
-
-namespace Robust.Server.GameStates;
-
-public struct ChunkIndicesEnumerator
-{
-    private Vector2i _bottomLeft;
-    private Vector2i _topRight;
-
-    private int _x;
-    private int _y;
-
-    public ChunkIndicesEnumerator(Vector2 viewPos, float range, float chunkSize)
-    {
-        var rangeVec = new Vector2(range, range);
-
-        _bottomLeft = ((viewPos - rangeVec) / chunkSize).Floored();
-        // Also floor this as we get the whole chunk anyway.
-        _topRight = ((viewPos + rangeVec) / chunkSize).Floored();
-
-        _x = _bottomLeft.X;
-        _y = _bottomLeft.Y;
-    }
-
-    public bool MoveNext([NotNullWhen(true)] out Vector2i? chunkIndices)
-    {
-        if (_y > _topRight.Y)
-        {
-            _x++;
-            _y = _bottomLeft.Y;
-        }
-
-        if (_x > _topRight.X)
-        {
-            chunkIndices = null;
-            return false;
-        }
-
-        chunkIndices = new Vector2i(_x, _y);
-
-        _y++;
-        return true;
-    }
-}

Robust.Server/GameStates/PvsSystem.Chunks.cs

@@ -8,6 +8,7 @@ using Prometheus;
 using Robust.Shared.Enums;
 using Robust.Shared.GameObjects;
 using Robust.Shared.Map.Components;
+using Robust.Shared.Map.Enumerators;
 using Robust.Shared.Maths;
 using Robust.Shared.Player;
 using Robust.Shared.Utility;

Robust.Server/GameStates/PvsSystem.cs

@@ -126,11 +126,12 @@ internal sealed partial class PvsSystem : EntitySystem
         _playerManager.PlayerStatusChanged += OnPlayerStatusChanged;
         _transform.OnGlobalMoveEvent += OnEntityMove;
 
-        _configManager.OnValueChanged(CVars.NetPVS, SetPvs, true);
-        _configManager.OnValueChanged(CVars.NetMaxUpdateRange, OnViewsizeChanged, true);
-        _configManager.OnValueChanged(CVars.NetLowLodRange, OnLodChanged, true);
-        _configManager.OnValueChanged(CVars.NetForceAckThreshold, OnForceAckChanged, true);
-        _configManager.OnValueChanged(CVars.NetPvsAsync, OnAsyncChanged, true);
+        Subs.CVar(_configManager, CVars.NetPVS, SetPvs, true);
+        Subs.CVar(_configManager, CVars.NetMaxUpdateRange, OnViewsizeChanged, true);
+        Subs.CVar(_configManager, CVars.NetLowLodRange, OnLodChanged, true);
+        Subs.CVar(_configManager, CVars.NetForceAckThreshold, OnForceAckChanged, true);
+        Subs.CVar(_configManager, CVars.NetPvsAsync, OnAsyncChanged, true);
+        Subs.CVar(_configManager, CVars.NetPvsCompressLevel, ResetParallelism, true);
 
         _serverGameStateManager.ClientAck += OnClientAck;
         _serverGameStateManager.ClientRequestFull += OnClientRequestFull;
@@ -138,7 +139,6 @@ internal sealed partial class PvsSystem : EntitySystem
         InitializeDirty();
 
         _parallelMgr.ParallelCountChanged += ResetParallelism;
-        _configManager.OnValueChanged(CVars.NetPvsCompressLevel, ResetParallelism, true);
     }
 
     public override void Shutdown()
@@ -148,10 +148,6 @@ internal sealed partial class PvsSystem : EntitySystem
         _playerManager.PlayerStatusChanged -= OnPlayerStatusChanged;
         _transform.OnGlobalMoveEvent -= OnEntityMove;
 
-        _configManager.UnsubValueChanged(CVars.NetPVS, SetPvs);
-        _configManager.UnsubValueChanged(CVars.NetMaxUpdateRange, OnViewsizeChanged);
-        _configManager.UnsubValueChanged(CVars.NetForceAckThreshold, OnForceAckChanged);
-        _configManager.UnsubValueChanged(CVars.NetPvsCompressLevel, ResetParallelism);
         _parallelMgr.ParallelCountChanged -= ResetParallelism;
 
         _serverGameStateManager.ClientAck -= OnClientAck;

Robust.Server/Physics/GridFixtureSystem.cs

@@ -64,7 +64,7 @@ namespace Robust.Server.Physics
             SubscribeNetworkEvent<RequestGridNodesMessage>(OnDebugRequest);
             SubscribeNetworkEvent<StopGridNodesMessage>(OnDebugStopRequest);
 
-            _cfg.OnValueChanged(CVars.GridSplitting, SetSplitAllowed, true);
+            Subs.CVar(_cfg, CVars.GridSplitting, SetSplitAllowed, true);
         }
 
         private void SetSplitAllowed(bool value) => SplitAllowed = value;
@@ -73,7 +73,6 @@ namespace Robust.Server.Physics
         {
             base.Shutdown();
             _subscribedSessions.Clear();
-            _cfg.UnsubValueChanged(CVars.GridSplitting, SetSplitAllowed);
         }
 
         /// <summary>

Robust.Shared.CompNetworkGenerator/ComponentNetworkGenerator.cs

@@ -32,7 +32,7 @@ namespace Robust.Shared.CompNetworkGenerator
         private const string GlobalHashSetName = "global::System.Collections.Generic.HashSet<T>";
         private const string GlobalListName = "global::System.Collections.Generic.List<T>";
 
-        private static string GenerateSource(in GeneratorExecutionContext context, INamedTypeSymbol classSymbol, CSharpCompilation comp, bool raiseAfterAutoHandle)
+        private static string? GenerateSource(in GeneratorExecutionContext context, INamedTypeSymbol classSymbol, CSharpCompilation comp, bool raiseAfterAutoHandle)
         {
             var nameSpace = classSymbol.ContainingNamespace.ToDisplayString();
             var componentName = classSymbol.Name;
@@ -280,10 +280,10 @@ public partial class {componentName}
                 {
                     var attr = type.Attribute;
                     var raiseEv = false;
-                    if (attr.ConstructorArguments.Length == 1 && attr.ConstructorArguments[0].Value != null)
+                    if (attr.ConstructorArguments is [{Value: bool raise}])
                     {
                         // Get the afterautohandle bool, which is first constructor arg
-                        raiseEv = (bool) attr.ConstructorArguments[0].Value;
+                        raiseEv = raise;
                     }
 
                     var source = GenerateSource(context, type.Type, comp, raiseEv);
@@ -325,11 +325,11 @@ public partial class {componentName}
                     attr.AttributeClass != null &&
                     attr.AttributeClass.Equals(attributeSymbol, SymbolEqualityComparer.Default));
 
+                if (typeSymbol == null)
+                    continue;
+
                 if (relevantAttribute == null)
                 {
-                    if (typeSymbol == null)
-                        continue;
-
                     foreach (var mem in typeSymbol.GetMembers())
                     {
                         var attribute = mem.GetAttributes().FirstOrDefault(a =>

Robust.Shared.CompNetworkGenerator/Robust.Shared.CompNetworkGenerator.csproj

@@ -1,13 +1,5 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
-  <PropertyGroup>
-    <TargetFramework>netstandard2.0</TargetFramework>
-    <LangVersion>9</LangVersion>
-    <ManagePackageVersionsCentrally>true</ManagePackageVersionsCentrally>
-  </PropertyGroup>
+  <Import Project="../Robust.Roslyn.Shared/Robust.Roslyn.Shared.props" />
 
-  <ItemGroup>
-    <PackageReference Include="Microsoft.CodeAnalysis.CSharp" PrivateAssets="all" />
-    <PackageReference Include="Microsoft.CodeAnalysis.Analyzers" PrivateAssets="all" />
-  </ItemGroup>
 </Project>

Robust.Shared.Maths/Box2.cs

@@ -186,10 +186,10 @@ namespace Robust.Shared.Maths
         [Pure]
         public readonly Box2 Intersect(in Box2 other)
         {
-            var ourLeftBottom = new Vector2(Left, Bottom);
-            var ourRightTop = new Vector2(Right, Top);
-            var otherLeftBottom = new Vector2(other.Left, other.Bottom);
-            var otherRightTop = new Vector2(other.Right, other.Top);
+            var ourLeftBottom = BottomLeft;
+            var ourRightTop = TopRight;
+            var otherLeftBottom = other.BottomLeft;
+            var otherRightTop = other.TopRight;
 
             var max = Vector2.Max(ourLeftBottom, otherLeftBottom);
             var min = Vector2.Min(ourRightTop, otherRightTop);
@@ -219,10 +219,10 @@ namespace Robust.Shared.Maths
         [Pure]
         public readonly Box2 Union(in Box2 other)
         {
-            var ourLeftBottom = new Vector2(Left, Bottom);
-            var otherLeftBottom = new Vector2(other.Left, other.Bottom);
-            var ourRightTop = new Vector2(Right, Top);
-            var otherRightTop = new Vector2(other.Right, other.Top);
+            var ourLeftBottom = BottomLeft;
+            var otherLeftBottom = other.BottomLeft;
+            var ourRightTop = TopRight;
+            var otherRightTop = other.TopRight;
 
             var leftBottom = Vector2.Min(ourLeftBottom, otherLeftBottom);
             var rightTop = Vector2.Max(ourRightTop, otherRightTop);

Robust.Shared.Maths/Box2Rotated.cs

@@ -3,6 +3,7 @@ using System.Numerics;
 using System.Runtime.CompilerServices;
 using System.Runtime.Intrinsics;
 using System.Runtime.Intrinsics.X86;
+using JetBrains.Annotations;
 using Robust.Shared.Utility;
 
 namespace Robust.Shared.Maths
@@ -57,7 +58,17 @@ namespace Robust.Shared.Maths
         }
 
         /// <summary>
-        /// calculates the smallest AABB that will encompass the rotated box. The AABB is in local space.
+        /// Enlarges the box by the specified value.
+        /// </summary>
+        [Pure]
+        public readonly Box2Rotated Enlarged(float value)
+        {
+            var box = Box.Enlarged(value);
+            return new Box2Rotated(box, Rotation, Origin);
+        }
+
+        /// <summary>
+        /// Calculates the smallest AABB that will encompass the rotated box. The AABB is in local space.
         /// </summary>
         public readonly Box2 CalcBoundingBox()
         {

Robust.Shared/Analyzers/ComponentPauseGeneratorAttributes.cs

@@ -0,0 +1,29 @@
+using System;
+using JetBrains.Annotations;
+using Robust.Shared.GameObjects;
+
+namespace Robust.Shared.Analyzers;
+
+/// <summary>
+/// Indicate that a <see cref="Component"/> should automatically handle unpausing of timer fields.
+/// </summary>
+/// <remarks>
+/// When this attribute is set on a <see cref="Component"/>, an <see cref="EntitySystem"/> will automatically be
+/// generated that increments any fields tagged with <see cref="AutoPausedFieldAttribute"/> when the entity is unpaused
+/// (<see cref="EntityUnpausedEvent"/>).
+/// </remarks>
+[AttributeUsage(AttributeTargets.Class, Inherited = false)]
+[BaseTypeRequired(typeof(IComponent))]
+public sealed class AutoGenerateComponentPauseAttribute : Attribute
+{
+    public bool Dirty = false;
+}
+
+/// <summary>
+/// Mark a field or property to automatically handle unpausing with <see cref="AutoGenerateComponentPauseAttribute"/>.
+/// </summary>
+/// <remarks>
+/// The type of the field or prototype must be <see cref="TimeSpan"/> (potentially nullable).
+/// </remarks>
+[AttributeUsage(AttributeTargets.Field | AttributeTargets.Property)]
+public sealed class AutoPausedFieldAttribute : Attribute;

Robust.Shared/Audio/Systems/SharedAudioSystem.cs

@@ -50,17 +50,11 @@ public abstract partial class SharedAudioSystem : EntitySystem
         base.Initialize();
         InitializeEffect();
         ZOffset = CfgManager.GetCVar(CVars.AudioZOffset);
-        CfgManager.OnValueChanged(CVars.AudioZOffset, SetZOffset);
+        Subs.CVar(CfgManager, CVars.AudioZOffset, SetZOffset);
         SubscribeLocalEvent<AudioComponent, ComponentGetStateAttemptEvent>(OnAudioGetStateAttempt);
         SubscribeLocalEvent<AudioComponent, EntityUnpausedEvent>(OnAudioUnpaused);
     }
 
-    public override void Shutdown()
-    {
-        base.Shutdown();
-        CfgManager.UnsubValueChanged(CVars.AudioZOffset, SetZOffset);
-    }
-
     protected void SetZOffset(float value)
     {
         ZOffset = value;

Robust.Shared/CVars.cs

@@ -1239,7 +1239,7 @@ namespace Robust.Shared
         /// Enable Discord rich presence integration.
         /// </summary>
         public static readonly CVarDef<bool> DiscordEnabled =
-            CVarDef.Create("discord.enabled", true, CVar.CLIENTONLY);
+            CVarDef.Create("discord.enabled", true, CVar.CLIENTONLY | CVar.ARCHIVE);
 
         public static readonly CVarDef<string> DiscordRichPresenceMainIconId =
             CVarDef.Create("discord.rich_main_icon_id", "devstation", CVar.SERVER | CVar.REPLICATED);

Robust.Shared/ContentPack/Sandbox.yml

@@ -73,6 +73,9 @@ WhitelistedNamespaces:
 # * The API is not *relevant* to content. e.g. System.Type.IsAnsiClass.
 # * I am lazy these API lists are huge dude.
 Types:
+  Avalonia.Metadata:
+    XmlnsDefinitionAttribute:
+      All: True
   NetSerializer:
     NetListAsArray`1:
       Fields:
@@ -626,6 +629,7 @@ Types:
       - "System.Text.Encoding get_UTF7()"
       - "System.Text.Encoding get_UTF8()"
       - "System.Text.Encoding get_UTF32()"
+      - "System.Text.Encoding GetEncoding(string)"
     NormalizationForm: { } # Enum
     Rune: { All: True }
     StringBuilder:
@@ -716,6 +720,9 @@ Types:
         ChunkEnumerator: { All: True }
         AppendInterpolatedStringHandler: { All: True }
     StringRuneEnumerator: { All: True }
+  System.Text.Unicode:
+    UnicodeRange: { All: True }
+    UnicodeRanges: { All: True }
   System.Threading.Tasks:
     Task: { All: True }
     Task`1: { All: True }

Robust.Shared/GameObjects/EntitySystem.Subscriptions.cs

@@ -1,12 +1,12 @@
 using System;
-using System.Collections.Generic;
 using JetBrains.Annotations;
+using Robust.Shared.Collections;
 
 namespace Robust.Shared.GameObjects
 {
     public abstract partial class EntitySystem
     {
-        private List<SubBase>? _subscriptions;
+        private ValueList<SubBase> _subscriptions;
 
         /// <summary>
         /// A handle to allow subscription on this entity system's behalf.
@@ -84,7 +84,6 @@ namespace Robust.Shared.GameObjects
         {
             EntityManager.EventBus.SubscribeEvent(src, this, handler, GetType(), before, after);
 
-            _subscriptions ??= new();
             _subscriptions.Add(new SubBroadcast<T>(src));
         }
 
@@ -96,7 +95,6 @@ namespace Robust.Shared.GameObjects
         {
             EntityManager.EventBus.SubscribeEvent(src, this, handler, GetType(), before, after);
 
-            _subscriptions ??= new();
             _subscriptions.Add(new SubBroadcast<T>(src));
         }
 
@@ -108,7 +106,6 @@ namespace Robust.Shared.GameObjects
         {
             EntityManager.EventBus.SubscribeSessionEvent(src, this, handler, GetType(), before, after);
 
-            _subscriptions ??= new();
             _subscriptions.Add(new SubBroadcast<EntitySessionMessage<T>>(src));
         }
 
@@ -122,7 +119,6 @@ namespace Robust.Shared.GameObjects
         {
             EntityManager.EventBus.SubscribeLocalEvent(handler, GetType(), before, after);
 
-            _subscriptions ??= new();
             _subscriptions.Add(new SubLocal<TComp, TEvent>());
         }
 
@@ -134,7 +130,6 @@ namespace Robust.Shared.GameObjects
         {
             EntityManager.EventBus.SubscribeLocalEvent(handler, GetType(), before, after);
 
-            _subscriptions ??= new();
             _subscriptions.Add(new SubLocal<TComp, TEvent>());
         }
 
@@ -146,21 +141,17 @@ namespace Robust.Shared.GameObjects
         {
             EntityManager.EventBus.SubscribeLocalEvent(handler, GetType(), before, after);
 
-            _subscriptions ??= new();
             _subscriptions.Add(new SubLocal<TComp, TEvent>());
         }
 
         private void ShutdownSubscriptions()
         {
-            if (_subscriptions == null)
-                return;
-
             foreach (var sub in _subscriptions)
             {
                 sub.Unsubscribe(this, EntityManager.EventBus);
             }
 
-            _subscriptions = null;
+            _subscriptions = default;
         }
 
         /// <summary>
@@ -232,6 +223,19 @@ namespace Robust.Shared.GameObjects
             {
                 System.SubscribeLocalEvent(handler, before, after);
             }
+
+            /// <summary>
+            /// Register an action to be ran when this entity system is shut down.
+            /// </summary>
+            /// <remarks>
+            /// This can be used by extension methods for <see cref="Subscriptions"/>
+            /// to unsubscribe from from external sources such as CVars.
+            /// </remarks>
+            /// <param name="action">An action to be ran when the entity system is shut down.</param>
+            public void RegisterUnsubscription(Action action)
+            {
+                System._subscriptions.Add(new SubAction(action));
+            }
         }
 
         private abstract class SubBase
@@ -261,5 +265,13 @@ namespace Robust.Shared.GameObjects
                 bus.UnsubscribeLocalEvent<TComp, TBase>();
             }
         }
+
+        private sealed class SubAction(Action action) : SubBase
+        {
+            public override void Unsubscribe(EntitySystem sys, IEventBus bus)
+            {
+                action();
+            }
+        }
     }
 }

Robust.Shared/GameObjects/EntitySystemSubscriptionExt.cs

@@ -0,0 +1,130 @@
+using System;
+using Robust.Shared.Configuration;
+
+namespace Robust.Shared.GameObjects;
+
+/// <summary>
+/// Extra subscription helpers for <see cref="EntitySystem"/> that are not part of the core entity system behavior.
+/// </summary>
+public static class EntitySystemSubscriptionExt
+{
+    /// <summary>
+    /// Listen for an event for if the config value changes.
+    /// </summary>
+    /// <remarks>
+    /// This is an O(n) operation.
+    /// </remarks>
+    /// <param name="subs">
+    /// The entity system subscriptions.
+    /// Call this with <see cref="EntitySystem.Subscriptions"/>.
+    /// </param>
+    /// <param name="cfg">The configuration manager.</param>
+    /// <param name="name">The name of the CVar to listen for.</param>
+    /// <param name="onValueChanged">The delegate to run when the value was changed.</param>
+    /// <param name="invokeImmediately">
+    /// Whether to run the callback immediately inw this method. Can help reduce boilerplate
+    /// </param>
+    /// <typeparam name="T">The type of value contained in this CVar.</typeparam>
+    public static void CVar<T>(
+        this EntitySystem.Subscriptions subs,
+        IConfigurationManager cfg,
+        string name,
+        Action<T> onValueChanged,
+        bool invokeImmediately = false)
+        where T : notnull
+    {
+        cfg.OnValueChanged(name, onValueChanged, invokeImmediately);
+
+        subs.RegisterUnsubscription(() => cfg.UnsubValueChanged(name, onValueChanged));
+    }
+
+    /// <summary>
+    /// Listen for an event for if the config value changes.
+    /// </summary>
+    /// <remarks>
+    /// This is an O(n) operation.
+    /// </remarks>
+    /// <param name="subs">
+    /// The entity system subscriptions.
+    /// Call this with <see cref="EntitySystem.Subscriptions"/>.
+    /// </param>
+    /// <param name="cfg">The configuration manager.</param>
+    /// <param name="cVar">The CVar to listen for.</param>
+    /// <param name="onValueChanged">The delegate to run when the value was changed.</param>
+    /// <param name="invokeImmediately">
+    /// Whether to run the callback immediately in this method. Can help reduce boilerplate
+    /// </param>
+    /// <typeparam name="T">The type of value contained in this CVar.</typeparam>
+    public static void CVar<T>(
+        this EntitySystem.Subscriptions subs,
+        IConfigurationManager cfg,
+        CVarDef<T> cVar,
+        Action<T> onValueChanged,
+        bool invokeImmediately = false)
+        where T : notnull
+    {
+        cfg.OnValueChanged(cVar, onValueChanged, invokeImmediately);
+
+        subs.RegisterUnsubscription(() => cfg.UnsubValueChanged(cVar, onValueChanged));
+    }
+
+    /// <summary>
+    /// Listen for an event for if the config value changes.
+    /// </summary>
+    /// <remarks>
+    /// This is an O(n) operation.
+    /// </remarks>
+    /// <param name="subs">
+    /// The entity system subscriptions.
+    /// Call this with <see cref="EntitySystem.Subscriptions"/>.
+    /// </param>
+    /// <param name="cfg">The configuration manager.</param>
+    /// <param name="name">The name of the CVar to listen for.</param>
+    /// <param name="onValueChanged">The delegate to run when the value was changed.</param>
+    /// <param name="invokeImmediately">
+    /// Whether to run the callback immediately in this method. Can help reduce boilerplate
+    /// </param>
+    /// <typeparam name="T">The type of value contained in this CVar.</typeparam>
+    public static void CVar<T>(
+        this EntitySystem.Subscriptions subs,
+        IConfigurationManager cfg,
+        string name,
+        CVarChanged<T> onValueChanged,
+        bool invokeImmediately = false)
+        where T : notnull
+    {
+        cfg.OnValueChanged(name, onValueChanged, invokeImmediately);
+
+        subs.RegisterUnsubscription(() => cfg.UnsubValueChanged(name, onValueChanged));
+    }
+
+    /// <summary>
+    /// Listen for an event for if the config value changes.
+    /// </summary>
+    /// <remarks>
+    /// This is an O(n) operation.
+    /// </remarks>
+    /// <param name="subs">
+    /// The entity system subscriptions.
+    /// Call this with <see cref="EntitySystem.Subscriptions"/>.
+    /// </param>
+    /// <param name="cfg">The configuration manager.</param>
+    /// <param name="cVar">The CVar to listen for.</param>
+    /// <param name="onValueChanged">The delegate to run when the value was changed.</param>
+    /// <param name="invokeImmediately">
+    /// Whether to run the callback immediately in this method. Can help reduce boilerplate
+    /// </param>
+    /// <typeparam name="T">The type of value contained in this CVar.</typeparam>
+    public static void CVar<T>(
+        this EntitySystem.Subscriptions subs,
+        IConfigurationManager cfg,
+        CVarDef<T> cVar,
+        CVarChanged<T> onValueChanged,
+        bool invokeImmediately = false)
+        where T : notnull
+    {
+        cfg.OnValueChanged(cVar, onValueChanged, invokeImmediately);
+
+        subs.RegisterUnsubscription(() => cfg.UnsubValueChanged(cVar, onValueChanged));
+    }
+}

Robust.Shared/GameObjects/Systems/SharedGridFixtureSystem.cs

@@ -36,8 +36,8 @@ namespace Robust.Shared.GameObjects
             base.Initialize();
             UpdatesBefore.Add(typeof(SharedBroadphaseSystem));
 
-            _cfg.OnValueChanged(CVars.GenerateGridFixtures, SetEnabled, true);
-            _cfg.OnValueChanged(CVars.GridFixtureEnlargement, SetEnlargement, true);
+            Subs.CVar(_cfg, CVars.GenerateGridFixtures, SetEnabled, true);
+            Subs.CVar(_cfg, CVars.GridFixtureEnlargement, SetEnlargement, true);
 
             SubscribeLocalEvent<GridInitializeEvent>(OnGridInit);
             SubscribeLocalEvent<RegenerateGridBoundsEvent>(OnGridBoundsRegenerate);
@@ -58,14 +58,6 @@ namespace Robust.Shared.GameObjects
             _map.RegenerateCollision(ev.EntityUid, grid, _map.GetMapChunks(ev.EntityUid, grid).Values.ToHashSet());
         }
 
-        public override void Shutdown()
-        {
-            base.Shutdown();
-
-            _cfg.UnsubValueChanged(CVars.GenerateGridFixtures, SetEnabled);
-            _cfg.UnsubValueChanged(CVars.GridFixtureEnlargement, SetEnlargement);
-        }
-
         private void SetEnabled(bool value) => _enabled = value;
 
         private void SetEnlargement(float value) => _fixtureEnlargement = value;

Robust.Shared/GameObjects/Systems/SharedMapSystem.Grid.cs

@@ -974,19 +974,34 @@ public abstract partial class SharedMapSystem
     internal ChunkEnumerator GetMapChunks(EntityUid uid, MapGridComponent grid, Box2 worldAABB)
     {
         var localAABB = _transform.GetInvWorldMatrix(uid).TransformBox(worldAABB);
-        return new ChunkEnumerator(grid.Chunks, localAABB, grid.ChunkSize);
+        return GetLocalMapChunks(uid, grid, localAABB);
     }
 
     internal ChunkEnumerator GetMapChunks(EntityUid uid, MapGridComponent grid, Box2Rotated worldArea)
     {
         var matrix = _transform.GetInvWorldMatrix(uid);
         var localArea = matrix.TransformBox(worldArea);
-        return new ChunkEnumerator(grid.Chunks, localArea, grid.ChunkSize);
+        return GetLocalMapChunks(uid, grid, localArea);
     }
 
     internal ChunkEnumerator GetLocalMapChunks(EntityUid uid, MapGridComponent grid, Box2 localAABB)
     {
-        return new ChunkEnumerator(grid.Chunks, localAABB, grid.ChunkSize);
+        Box2 compAABB;
+
+        // The entire area intersects.
+        if (_mapQuery.HasComponent(uid))
+        {
+            compAABB = localAABB;
+        }
+        else
+        {
+            compAABB = grid.LocalAABB.Intersect(localAABB);
+        }
+
+        if (compAABB.IsEmpty())
+            return ChunkEnumerator.Empty;
+
+        return new ChunkEnumerator(grid.Chunks, compAABB, grid.ChunkSize);
     }
 
     #endregion ChunkAccess

Robust.Shared/Map/Enumerators/ChunkEnumerator.cs

@@ -1,12 +1,19 @@
 using System;
 using System.Collections.Generic;
 using System.Diagnostics.CodeAnalysis;
+using Robust.Shared.GameObjects;
+using Robust.Shared.Map.Components;
 using Robust.Shared.Maths;
 
 namespace Robust.Shared.Map.Enumerators;
 
 internal struct ChunkEnumerator
 {
+    /// <summary>
+    /// An empty enumerator that will return nothing.
+    /// </summary>
+    public static ChunkEnumerator Empty => new(new Dictionary<Vector2i, MapChunk>(), Box2.Empty, 1);
+
     private Dictionary<Vector2i, MapChunk> _chunks;
     private Vector2i _chunkLB;
     private Vector2i _chunkRT;

Robust.Shared/Map/Enumerators/ChunkIndicesEnumerator.cs

@@ -0,0 +1,59 @@
+using System;
+using System.Diagnostics.CodeAnalysis;
+using System.Numerics;
+using Robust.Shared.Maths;
+
+namespace Robust.Shared.Map.Enumerators;
+
+/// <summary>
+/// Generic iterator for chunk indices for the specified bounds with the specified chunk size.
+/// </summary>
+public struct ChunkIndicesEnumerator
+{
+    private readonly Vector2i _chunkLB;
+    private readonly Vector2i _chunkRT;
+
+    private int _xIndex;
+    private int _yIndex;
+
+    public ChunkIndicesEnumerator(Vector2 viewPos, float range, float chunkSize)
+    {
+        var rangeVec = new Vector2(range, range);
+
+        _chunkLB = ((viewPos - rangeVec) / chunkSize).Floored();
+        // Also floor this as we get the whole chunk anyway.
+        _chunkRT = ((viewPos + rangeVec) / chunkSize).Floored();
+
+        _xIndex = _chunkLB.X;
+        _yIndex = _chunkLB.Y;
+    }
+
+    public ChunkIndicesEnumerator(Box2 localAABB, int chunkSize)
+    {
+        _chunkLB = (localAABB.BottomLeft / chunkSize).Floored();
+        _chunkRT = (localAABB.TopRight / chunkSize).Floored();
+
+        _xIndex = _chunkLB.X;
+        _yIndex = _chunkLB.Y;
+    }
+
+    public bool MoveNext([NotNullWhen(true)] out Vector2i? indices)
+    {
+        if (_yIndex > _chunkRT.Y)
+        {
+            _yIndex = _chunkLB.Y;
+            _xIndex++;
+        }
+
+        if (_xIndex > _chunkRT.X)
+        {
+            indices = null;
+            return false;
+        }
+
+        indices = new Vector2i(_xIndex, _yIndex);
+        _yIndex++;
+
+        return true;
+    }
+}

Robust.Shared/Network/NetUserId.cs

@@ -4,7 +4,7 @@ using Robust.Shared.Serialization;
 namespace Robust.Shared.Network
 {
     [Serializable, NetSerializable]
-    public struct NetUserId : IEquatable<NetUserId>
+    public struct NetUserId : IEquatable<NetUserId>, ISelfSerialize
     {
         public readonly Guid UserId;
 
@@ -32,5 +32,15 @@ namespace Robust.Shared.Network
 
         public static implicit operator Guid(NetUserId id) => id.UserId;
         public static explicit operator NetUserId(Guid id) => new(id);
+
+        void ISelfSerialize.Deserialize(string value)
+        {
+            this = (NetUserId) Guid.Parse(value);
+        }
+
+        string ISelfSerialize.Serialize()
+        {
+            return ToString();
+        }
     }
 }

Robust.Shared/Physics/PhysicsConstants.cs

@@ -2,7 +2,7 @@
 
 namespace Robust.Shared.Physics
 {
-    internal static class PhysicsConstants
+    public static class PhysicsConstants
     {
         /// <summary>
         /// The radius of the polygon/edge shape skin. This should not be modified. Making

Robust.Shared/Physics/Systems/SharedBroadphaseSystem.cs

@@ -67,14 +67,7 @@ namespace Robust.Shared.Physics.Systems
             UpdatesOutsidePrediction = true;
             UpdatesAfter.Add(typeof(SharedTransformSystem));
 
-            _cfg.OnValueChanged(CVars.BroadphaseExpand, SetBroadphaseExpand, true);
-        }
-
-        public override void Shutdown()
-        {
-            base.Shutdown();
-
-            _cfg.UnsubValueChanged(CVars.BroadphaseExpand, SetBroadphaseExpand);
+            Subs.CVar(_cfg, CVars.BroadphaseExpand, SetBroadphaseExpand, true);
         }
 
         private void SetBroadphaseExpand(float value) => _broadphaseExpand = value;

Robust.Shared/Physics/Systems/SharedPhysicsSystem.Island.cs

@@ -199,38 +199,20 @@ public abstract partial class SharedPhysicsSystem
 
     private void InitializeIsland()
     {
-        _configManager.OnValueChanged(CVars.NetTickrate, SetTickRate, true);
-        _configManager.OnValueChanged(CVars.WarmStarting, SetWarmStarting, true);
-        _configManager.OnValueChanged(CVars.MaxLinearCorrection, SetMaxLinearCorrection, true);
-        _configManager.OnValueChanged(CVars.MaxAngularCorrection, SetMaxAngularCorrection, true);
-        _configManager.OnValueChanged(CVars.VelocityIterations, SetVelocityIterations, true);
-        _configManager.OnValueChanged(CVars.PositionIterations, SetPositionIterations, true);
-        _configManager.OnValueChanged(CVars.MaxLinVelocity, SetMaxLinearVelocity, true);
-        _configManager.OnValueChanged(CVars.MaxAngVelocity, SetMaxAngularVelocity, true);
-        _configManager.OnValueChanged(CVars.SleepAllowed, SetSleepAllowed, true);
-        _configManager.OnValueChanged(CVars.AngularSleepTolerance, SetAngularToleranceSqr, true);
-        _configManager.OnValueChanged(CVars.LinearSleepTolerance, SetLinearToleranceSqr, true);
-        _configManager.OnValueChanged(CVars.TimeToSleep, SetTimeToSleep, true);
-        _configManager.OnValueChanged(CVars.VelocityThreshold, SetVelocityThreshold, true);
-        _configManager.OnValueChanged(CVars.Baumgarte, SetBaumgarte, true);
-    }
-
-    private void ShutdownIsland()
-    {
-        _configManager.UnsubValueChanged(CVars.NetTickrate, SetTickRate);
-        _configManager.UnsubValueChanged(CVars.WarmStarting, SetWarmStarting);
-        _configManager.UnsubValueChanged(CVars.MaxLinearCorrection, SetMaxLinearCorrection);
-        _configManager.UnsubValueChanged(CVars.MaxAngularCorrection, SetMaxAngularCorrection);
-        _configManager.UnsubValueChanged(CVars.VelocityIterations, SetVelocityIterations);
-        _configManager.UnsubValueChanged(CVars.PositionIterations, SetPositionIterations);
-        _configManager.UnsubValueChanged(CVars.MaxLinVelocity, SetMaxLinearVelocity);
-        _configManager.UnsubValueChanged(CVars.MaxAngVelocity, SetMaxAngularVelocity);
-        _configManager.UnsubValueChanged(CVars.SleepAllowed, SetSleepAllowed);
-        _configManager.UnsubValueChanged(CVars.AngularSleepTolerance, SetAngularToleranceSqr);
-        _configManager.UnsubValueChanged(CVars.LinearSleepTolerance, SetLinearToleranceSqr);
-        _configManager.UnsubValueChanged(CVars.TimeToSleep, SetTimeToSleep);
-        _configManager.UnsubValueChanged(CVars.VelocityThreshold, SetVelocityThreshold);
-        _configManager.UnsubValueChanged(CVars.Baumgarte, SetBaumgarte);
+        Subs.CVar(_configManager, CVars.NetTickrate, SetTickRate, true);
+        Subs.CVar(_configManager, CVars.WarmStarting, SetWarmStarting, true);
+        Subs.CVar(_configManager, CVars.MaxLinearCorrection, SetMaxLinearCorrection, true);
+        Subs.CVar(_configManager, CVars.MaxAngularCorrection, SetMaxAngularCorrection, true);
+        Subs.CVar(_configManager, CVars.VelocityIterations, SetVelocityIterations, true);
+        Subs.CVar(_configManager, CVars.PositionIterations, SetPositionIterations, true);
+        Subs.CVar(_configManager, CVars.MaxLinVelocity, SetMaxLinearVelocity, true);
+        Subs.CVar(_configManager, CVars.MaxAngVelocity, SetMaxAngularVelocity, true);
+        Subs.CVar(_configManager, CVars.SleepAllowed, SetSleepAllowed, true);
+        Subs.CVar(_configManager, CVars.AngularSleepTolerance, SetAngularToleranceSqr, true);
+        Subs.CVar(_configManager, CVars.LinearSleepTolerance, SetLinearToleranceSqr, true);
+        Subs.CVar(_configManager, CVars.TimeToSleep, SetTimeToSleep, true);
+        Subs.CVar(_configManager, CVars.VelocityThreshold, SetVelocityThreshold, true);
+        Subs.CVar(_configManager, CVars.Baumgarte, SetBaumgarte, true);
     }
 
     private void SetWarmStarting(bool value) => _warmStarting = value;

Robust.Shared/Physics/Systems/SharedPhysicsSystem.cs

@@ -92,9 +92,9 @@ namespace Robust.Shared.Physics.Systems
             InitializeIsland();
             InitializeContacts();
 
-            _configManager.OnValueChanged(CVars.AutoClearForces, OnAutoClearChange);
-            _configManager.OnValueChanged(CVars.NetTickrate, UpdateSubsteps, true);
-            _configManager.OnValueChanged(CVars.TargetMinimumTickrate, UpdateSubsteps, true);
+            Subs.CVar(_configManager, CVars.AutoClearForces, OnAutoClearChange);
+            Subs.CVar(_configManager, CVars.NetTickrate, UpdateSubsteps, true);
+            Subs.CVar(_configManager, CVars.TargetMinimumTickrate, UpdateSubsteps, true);
         }
 
         private void OnPhysicsShutdown(EntityUid uid, PhysicsComponent component, ComponentShutdown args)
@@ -250,8 +250,6 @@ namespace Robust.Shared.Physics.Systems
             base.Shutdown();
 
             ShutdownContacts();
-            ShutdownIsland();
-            _configManager.UnsubValueChanged(CVars.AutoClearForces, OnAutoClearChange);
         }
 
         private void UpdateMapAwakeState(EntityUid uid, PhysicsComponent body)

Robust.Shared/Physics/VerticesSimplifier.cs

@@ -56,17 +56,17 @@ namespace Robust.Shared.Physics
             return simplified;
         }
 
-        private bool IsCollinear(in Vector2 prev, in Vector2 current, in Vector2 next, float tolerance)
+        public static bool IsCollinear(in Vector2 prev, in Vector2 current, in Vector2 next, float tolerance)
         {
             return FloatInRange(Area(in prev, in current, in next), -tolerance, tolerance);
         }
 
-        private float Area(in Vector2 a, in Vector2 b, in Vector2 c)
+        private static float Area(in Vector2 a, in Vector2 b, in Vector2 c)
         {
             return a.X * (b.Y - c.Y) + b.X * (c.Y - a.Y) + c.X * (a.Y - b.Y);
         }
 
-        private bool FloatInRange(float value, float min, float max)
+        private static bool FloatInRange(float value, float min, float max)
         {
             return (value >= min && value <= max);
         }

Robust.Shared/Serialization/TypeSerializers/Implementations/DateTimeSerializer.cs

@@ -0,0 +1,65 @@
+using System;
+using System.Globalization;
+using JetBrains.Annotations;
+using Robust.Shared.IoC;
+using Robust.Shared.Serialization.Manager;
+using Robust.Shared.Serialization.Manager.Attributes;
+using Robust.Shared.Serialization.Markdown;
+using Robust.Shared.Serialization.Markdown.Validation;
+using Robust.Shared.Serialization.Markdown.Value;
+using Robust.Shared.Serialization.TypeSerializers.Interfaces;
+
+namespace Robust.Shared.Serialization.TypeSerializers.Implementations;
+
+/// <summary>
+/// Implements serialization for <see cref="DateTime"/>.
+/// </summary>
+/// <remarks>
+/// Serialization is implemented with <see cref="DateTimeStyles.RoundtripKind"/> and the "o" format specifier.
+/// </remarks>
+[TypeSerializer]
+public sealed class DateTimeSerializer : ITypeSerializer<DateTime, ValueDataNode>, ITypeCopyCreator<DateTime>
+{
+    public ValidationNode Validate(
+        ISerializationManager serializationManager,
+        ValueDataNode node,
+        IDependencyCollection dependencies,
+        ISerializationContext? context = null)
+    {
+        return DateTime.TryParse(node.Value, null, DateTimeStyles.RoundtripKind, out _)
+            ? new ValidatedValueNode(node)
+            : new ErrorNode(node, "Failed parsing DateTime");
+    }
+
+    public DateTime Read(
+        ISerializationManager serializationManager,
+        ValueDataNode node,
+        IDependencyCollection dependencies,
+        SerializationHookContext hookCtx,
+        ISerializationContext? context = null,
+        ISerializationManager.InstantiationDelegate<DateTime>? instanceProvider = null)
+    {
+        return DateTime.Parse(node.Value, null, DateTimeStyles.RoundtripKind);
+    }
+
+    public DataNode Write(
+        ISerializationManager serializationManager,
+        DateTime value,
+        IDependencyCollection dependencies,
+        bool alwaysWrite = false,
+        ISerializationContext? context = null)
+    {
+        return new ValueDataNode(value.ToString("o"));
+    }
+
+    [MustUseReturnValue]
+    public DateTime CreateCopy(
+        ISerializationManager serializationManager,
+        DateTime source,
+        IDependencyCollection dependencies,
+        SerializationHookContext hookCtx,
+        ISerializationContext? context = null)
+    {
+        return source;
+    }
+}

Robust.UnitTesting/RobustIntegrationTest.cs

@@ -759,8 +759,9 @@ namespace Robust.UnitTesting
 
         public sealed class ClientIntegrationInstance : IntegrationInstance
         {
+            [Obsolete("Use Session instead")]
             public LocalPlayer? Player => ((IPlayerManager) PlayerMan).LocalPlayer;
-            public ICommonSession? Session => Player?.Session;
+            public ICommonSession? Session => ((IPlayerManager) PlayerMan).LocalSession;
             public NetUserId? User => Session?.UserId;
             public EntityUid? AttachedEntity => Session?.AttachedEntity;
 

Robust.UnitTesting/Shared/Networking/DisconnectTest.cs

@@ -73,8 +73,8 @@ public sealed class DisconnectTest : RobustIntegrationTest
 
             session = sPlayerMan.Sessions.Single();
             Assert.That(session.Status, Is.EqualTo(SessionStatus.Connected));
-            Assert.That(session.UserId, Is.EqualTo(cPlayerMan!.LocalPlayer?.UserId));
-            Assert.That(cPlayerMan.LocalPlayer, Is.Not.Null);
+            Assert.That(session.UserId, Is.EqualTo(cPlayerMan.LocalUser));
+            Assert.That(cPlayerMan.LocalSession, Is.Not.Null);
         }
 
         void AssertDisconnected()

Robust.UnitTesting/Shared/Serialization/TypeSerializers/DateTimeSerializerTest.cs

@@ -0,0 +1,31 @@
+using System;
+using System.Globalization;
+using NUnit.Framework;
+using Robust.Shared.Serialization.Manager;
+using Robust.Shared.Serialization.Markdown.Value;
+using Robust.Shared.Serialization.TypeSerializers.Implementations;
+
+namespace Robust.UnitTesting.Shared.Serialization.TypeSerializers;
+
+[TestFixture]
+[TestOf(typeof(DateTimeSerializer))]
+internal sealed class DateTimeSerializerTest : SerializationTest
+{
+    [Test]
+    public void WriteTest()
+    {
+        var dateTime = DateTime.UtcNow;
+        var result = Serialization.WriteValueAs<ValueDataNode>(dateTime);
+
+        var parsed = DateTime.Parse(result.Value, null, DateTimeStyles.RoundtripKind);
+        Assert.That(parsed, Is.EqualTo(dateTime));
+    }
+
+    [Test]
+    public void ReadTest()
+    {
+        var result = Serialization.Read<DateTime>(new ValueDataNode("2020-07-10 15:00:00.000"));
+
+        Assert.That(result, Is.EqualTo(new DateTime(2020, 07, 10, 15, 0, 0)));
+    }
+}