Add unit test for ByRefEventAnalyzer

Robust.Analyzers.Tests/ByRefEventAnalyzerTest.cs

@@ -0,0 +1,114 @@
+using System.Threading.Tasks;
+using Microsoft.CodeAnalysis.CSharp.Testing;
+using Microsoft.CodeAnalysis.Testing;
+using NUnit.Framework;
+using VerifyCS =
+    Microsoft.CodeAnalysis.CSharp.Testing.CSharpAnalyzerVerifier<Robust.Analyzers.ByRefEventAnalyzer, Microsoft.CodeAnalysis.Testing.DefaultVerifier>;
+
+namespace Robust.Analyzers.Tests;
+
+[Parallelizable(ParallelScope.All | ParallelScope.Fixtures)]
+[TestFixture, TestOf(typeof(ByRefEventAnalyzer))]
+public sealed class ByRefEventAnalyzerTest
+{
+    private const string EventBusDef = """
+        namespace Robust.Shared.GameObjects;
+
+        public readonly struct EntityUid;
+
+        public sealed class EntitySystem
+        {
+            public void RaiseLocalEvent<TEvent>(EntityUid uid, ref TEvent args, bool broadcast = false)
+                where TEvent : notnull { }
+
+            public void RaiseLocalEvent<TEvent>(EntityUid uid, TEvent args, bool broadcast = false)
+                where TEvent : notnull { }
+        }
+
+        public sealed class EntityEventBus
+        {
+            public void RaiseLocalEvent<TEvent>(EntityUid uid, ref TEvent args, bool broadcast = false)
+                where TEvent : notnull { }
+
+            public void RaiseLocalEvent<TEvent>(EntityUid uid, TEvent args, bool broadcast = false)
+                where TEvent : notnull { }
+        }
+        """;
+
+    private static Task Verifier(string code, params DiagnosticResult[] expected)
+    {
+        var test = new CSharpAnalyzerTest<ByRefEventAnalyzer, DefaultVerifier>()
+        {
+            TestState =
+            {
+                Sources = { code }
+            },
+        };
+
+        TestHelper.AddEmbeddedSources(
+            test.TestState,
+            "Robust.Shared.GameObjects.EventBusAttributes.cs"
+        );
+
+        test.TestState.Sources.Add(("EntityEventBus.cs", EventBusDef));
+
+        // ExpectedDiagnostics cannot be set, so we need to AddRange here...
+        test.TestState.ExpectedDiagnostics.AddRange(expected);
+
+        return test.RunAsync();
+    }
+
+    [Test]
+    public async Task TestSuccess()
+    {
+        const string code = """
+            using Robust.Shared.GameObjects;
+
+            [ByRefEvent]
+            public readonly struct RefEvent;
+            public readonly struct ValueEvent;
+
+            public static class Foo
+            {
+                public static void Bar(EntityEventBus bus)
+                {
+                    bus.RaiseLocalEvent(default(EntityUid), new ValueEvent());
+                    var refEv = new RefEvent();
+                    bus.RaiseLocalEvent(default(EntityUid), ref refEv);
+                }
+            }
+            """;
+
+        await Verifier(code);
+    }
+
+    [Test]
+    public async Task TestWrong()
+    {
+        const string code = """
+            using Robust.Shared.GameObjects;
+
+            [ByRefEvent]
+            public readonly struct RefEvent;
+            public readonly struct ValueEvent;
+
+            public static class Foo
+            {
+                public static void Bar(EntityEventBus bus)
+                {
+                    bus.RaiseLocalEvent(default(EntityUid), new RefEvent());
+                    var valueEv = new ValueEvent();
+                    bus.RaiseLocalEvent(default(EntityUid), ref valueEv);
+                }
+            }
+            """;
+
+        await Verifier(
+            code,
+            // /0/Test0.cs(11,49): error RA0015: Tried to raise a by-ref event 'RefEvent' by value
+            VerifyCS.Diagnostic(ByRefEventAnalyzer.ByRefEventRaisedByValueRule).WithSpan(11, 49, 11, 63).WithArguments("RefEvent"),
+            // /0/Test0.cs(13,49): error RA0016: Tried to raise a value event 'ValueEvent' by-ref
+            VerifyCS.Diagnostic(ByRefEventAnalyzer.ByValueEventRaisedByRefRule).WithSpan(13, 49, 13, 60).WithArguments("ValueEvent")
+        );
+    }
+}

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

@@ -14,6 +14,7 @@
     <EmbeddedResource Include="..\Robust.Shared\Analyzers\PreferNonGenericVariantForAttribute.cs" LogicalName="Robust.Shared.Analyzers.PreferNonGenericVariantForAttribute.cs" LinkBase="Implementations" />
     <EmbeddedResource Include="..\Robust.Shared\Analyzers\PreferOtherTypeAttribute.cs" LogicalName="Robust.Shared.Analyzers.PreferOtherTypeAttribute.cs" LinkBase="Implementations" />
     <EmbeddedResource Include="..\Robust.Shared\IoC\DependencyAttribute.cs" LogicalName="Robust.Shared.IoC.DependencyAttribute.cs" LinkBase="Implementations" />
+    <EmbeddedResource Include="..\Robust.Shared\GameObjects\EventBusAttributes.cs" LogicalName="Robust.Shared.GameObjects.EventBusAttributes.cs" LinkBase="Implementations" />
   </ItemGroup>
 
   <PropertyGroup>

Robust.Analyzers/ByRefEventAnalyzer.cs

@@ -1,4 +1,4 @@
-#nullable enable
+#nullable enable
 using System.Collections.Immutable;
 using System.Linq;
 using Microsoft.CodeAnalysis;
@@ -24,7 +24,7 @@ public sealed class ByRefEventAnalyzer : DiagnosticAnalyzer
         "Make sure that methods subscribing to a ref event have the ref keyword for the event argument."
     );
 
-    private static readonly DiagnosticDescriptor ByRefEventRaisedByValueRule = new(
+    public static readonly DiagnosticDescriptor ByRefEventRaisedByValueRule = new(
         Diagnostics.IdByRefEventRaisedByValue,
         "By-ref event raised by value",
         "Tried to raise a by-ref event '{0}' by value",
@@ -34,7 +34,7 @@ public sealed class ByRefEventAnalyzer : DiagnosticAnalyzer
         "Make sure to use the ref keyword when raising ref events."
     );
 
-    private static readonly DiagnosticDescriptor ByValueEventRaisedByRefRule = new(
+    public static readonly DiagnosticDescriptor ByValueEventRaisedByRefRule = new(
         Diagnostics.IdValueEventRaisedByRef,
         "Value event raised by-ref",
         "Tried to raise a value event '{0}' by-ref",