perf: skip unannotated property data-source candidates

src/TUnit.Core.SourceGenerator/Generators/PropertyInjectionSourceGenerator.cs

@@ -1,6 +1,7 @@
 using System.Collections.Immutable;
 using System.Text;
 using Microsoft.CodeAnalysis;
+using Microsoft.CodeAnalysis.CSharp;
 using Microsoft.CodeAnalysis.CSharp.Syntax;
 using TUnit.Core.SourceGenerator.Extensions;
 using TUnit.Core.SourceGenerator.Helpers;
@@ -26,9 +27,11 @@ public void Initialize(IncrementalGeneratorInitializationContext context)
             });
 
         // Pipeline 1: Find properties with IDataSourceAttribute and group by containing class
+        // Partial properties can receive attributes from their other declaration.
         var propertyDataSources = context.SyntaxProvider
             .CreateSyntaxProvider(
-                predicate: static (node, _) => node is PropertyDeclarationSyntax,
+                predicate: static (node, _) => node is PropertyDeclarationSyntax property
+                    && (property.AttributeLists.Count > 0 || property.Modifiers.Any(SyntaxKind.PartialKeyword)),
                 transform: static (ctx, _) => ExtractPropertyDataSource(ctx))
             .Where(static x => x is not null)
             .Select(static (x, _) => x!);

tests/TUnit.Core.SourceGenerator.Tests/PropertyInjectionIncrementalTests.cs

@@ -0,0 +1,87 @@
+using Microsoft.CodeAnalysis;
+using Microsoft.CodeAnalysis.CSharp;
+using TUnit.Core.SourceGenerator.Generators;
+
+namespace TUnit.Core.SourceGenerator.Tests;
+
+public class PropertyInjectionIncrementalTests
+{
+    private const string Source = """
+        using TUnit.Core;
+        public class Fixture { }
+        public class Tests
+        {
+            [ClassDataSource<Fixture>]
+            public Fixture Value { get; set; }
+        }
+        """;
+
+    [Test]
+    public async Task AddingAndRemovingReferenceRefreshesCompilationTypes()
+    {
+        var withoutCore = ReferencesHelper.References
+            .Where(reference => !string.Equals(Path.GetFileName(reference.FilePath), "TUnit.Core.dll", StringComparison.OrdinalIgnoreCase))
+            .ToArray();
+        var compilation = CreateCompilation().WithReferences(withoutCore);
+        GeneratorDriver driver = CSharpGeneratorDriver.Create(new PropertyInjectionSourceGenerator());
+
+        driver = driver.RunGenerators(compilation);
+        await Assert.That(driver.GetRunResult().GeneratedTrees).IsEmpty();
+
+        compilation = compilation.WithReferences(ReferencesHelper.References);
+        await Assert.That(compilation.GetDiagnostics().Where(d => d.Severity == DiagnosticSeverity.Error)).IsEmpty();
+        driver = driver.RunGenerators(compilation);
+        await Assert.That(GetSource(driver)).Contains("PropertyName = \"Value\"");
+
+        driver = driver.RunGenerators(compilation.WithReferences(withoutCore));
+        await Assert.That(driver.GetRunResult().GeneratedTrees).IsEmpty();
+        await Assert.That(driver.GetRunResult().Diagnostics.Where(d => d.Severity == DiagnosticSeverity.Error)).IsEmpty();
+    }
+
+    [Test]
+    public async Task PropertyEditUpdatesReusedDriver()
+    {
+        var compilation = CreateCompilation();
+        GeneratorDriver driver = CSharpGeneratorDriver.Create(new PropertyInjectionSourceGenerator());
+        driver = driver.RunGenerators(compilation);
+        await Assert.That(GetSource(driver)).Contains("PropertyName = \"Value\"");
+
+        var originalTree = compilation.SyntaxTrees.Single();
+        compilation = compilation.ReplaceSyntaxTree(originalTree,
+            CSharpSyntaxTree.ParseText(Source.Replace("Value", "Renamed")));
+        driver = driver.RunGenerators(compilation);
+
+        await Assert.That(GetSource(driver)).Contains("PropertyName = \"Renamed\"");
+        await Assert.That(GetSource(driver)).DoesNotContain("PropertyName = \"Value\"");
+        await Assert.That(driver.GetRunResult().Diagnostics.Where(d => d.Severity == DiagnosticSeverity.Error)).IsEmpty();
+    }
+
+    private static string GetSource(GeneratorDriver driver) =>
+        string.Join("\n", driver.GetRunResult().GeneratedTrees.Select(tree => tree.ToString()));
+
+    [Test]
+    public async Task AddingAndRemovingAttributeUpdatesReusedDriver()
+    {
+        var plainSource = Source.Replace("[ClassDataSource<Fixture>]", "");
+        var compilation = CreateCompilation().RemoveAllSyntaxTrees().AddSyntaxTrees(CSharpSyntaxTree.ParseText(plainSource));
+        GeneratorDriver driver = CSharpGeneratorDriver.Create(new PropertyInjectionSourceGenerator());
+        driver = driver.RunGenerators(compilation);
+        await Assert.That(driver.GetRunResult().GeneratedTrees).IsEmpty();
+
+        compilation = compilation.ReplaceSyntaxTree(compilation.SyntaxTrees.Single(), CSharpSyntaxTree.ParseText(Source));
+        driver = driver.RunGenerators(compilation);
+        await Assert.That(GetSource(driver)).Contains("PropertyName = \"Value\"");
+
+        compilation = compilation.ReplaceSyntaxTree(compilation.SyntaxTrees.Single(), CSharpSyntaxTree.ParseText(plainSource));
+        driver = driver.RunGenerators(compilation);
+        await Assert.That(driver.GetRunResult().GeneratedTrees).IsEmpty();
+        await Assert.That(driver.GetRunResult().Diagnostics.Where(d => d.Severity == DiagnosticSeverity.Error)).IsEmpty();
+    }
+
+    private static CSharpCompilation CreateCompilation() => CSharpCompilation.Create(
+        "PropertyInjectionEdits",
+        [CSharpSyntaxTree.ParseText(Source)],
+        ReferencesHelper.References,
+        new CSharpCompilationOptions(OutputKind.DynamicallyLinkedLibrary));
+}
+