Add shared test infra for RDF and RDG (#46838)

Author: captainsafia

src/Http/Http.Extensions/test/RequestDelegateGenerator/CompileTimeGeneratorTests.cs

@@ -0,0 +1,84 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+using Microsoft.CodeAnalysis;
+namespace Microsoft.AspNetCore.Http.Generators.Tests;
+
+public class CompileTimeGeneratorTests : RequestDelegateGeneratorTests
+{
+    protected override bool IsGeneratorEnabled { get; } = true;
+
+    [Fact]
+    public async Task MapAction_UnknownParameter_EmitsDiagnostic_NoSource()
+    {
+        // This will eventually be handled by the EndpointParameterSource.JsonBodyOrService.
+        // All parameters should theoretically be handleable with enough "Or"s in the future
+        // we'll remove this test and diagnostic.
+        var source = """
+app.MapGet("/", (IServiceProvider provider) => "Hello world!");
+""";
+        var expectedBody = "Hello world!";
+        var (generatorRunResult, compilation) = await RunGeneratorAsync(source);
+
+        // Emits diagnostic but generates no source
+        var result = Assert.IsType<GeneratorRunResult>(generatorRunResult);
+        var diagnostic = Assert.Single(result.Diagnostics);
+        Assert.Equal(DiagnosticDescriptors.GetUnableToResolveParameterDescriptor("provider").Id, diagnostic.Id);
+        Assert.Empty(result.GeneratedSources);
+
+        // Falls back to runtime-generated endpoint
+        var endpoint = GetEndpointFromCompilation(compilation, false);
+
+        var httpContext = CreateHttpContext();
+        await endpoint.RequestDelegate(httpContext);
+        await VerifyResponseBodyAsync(httpContext, expectedBody);
+    }
+
+    [Fact]
+    public async Task MapGet_WithRequestDelegate_DoesNotGenerateSources()
+    {
+        var (generatorRunResult, compilation) = await RunGeneratorAsync("""
+app.MapGet("/hello", (HttpContext context) => Task.CompletedTask);
+""");
+        var results = Assert.IsType<GeneratorRunResult>(generatorRunResult);
+        Assert.Empty(GetStaticEndpoints(results, GeneratorSteps.EndpointModelStep));
+
+        var endpoint = GetEndpointFromCompilation(compilation, false);
+
+        var httpContext = CreateHttpContext();
+        await endpoint.RequestDelegate(httpContext);
+        await VerifyResponseBodyAsync(httpContext, "");
+    }
+
+    // Todo: Move this to a shared test that checks metadata once that is supported
+    // in the source generator.
+    [Theory]
+    [InlineData(@"app.MapGet(""/"", () => Console.WriteLine(""Returns void""));", null)]
+    [InlineData(@"app.MapGet(""/"", () => TypedResults.Ok(""Alright!""));", null)]
+    [InlineData(@"app.MapGet(""/"", () => Results.NotFound(""Oops!""));", null)]
+    [InlineData(@"app.MapGet(""/"", () => Task.FromResult(new Todo() { Name = ""Test Item""}));", "application/json")]
+    [InlineData(@"app.MapGet(""/"", () => ""Hello world!"");", "text/plain")]
+    public async Task MapAction_ProducesCorrectContentType(string source, string expectedContentType)
+    {
+        var (result, compilation) = await RunGeneratorAsync(source);
+
+        VerifyStaticEndpointModel(result, endpointModel =>
+        {
+            Assert.Equal("/", endpointModel.RoutePattern);
+            Assert.Equal("MapGet", endpointModel.HttpMethod);
+            Assert.Equal(expectedContentType, endpointModel.Response.ContentType);
+        });
+    }
+
+    [Fact]
+    public async Task MapAction_ExplicitRouteParamWithInvalidName_SimpleReturn()
+    {
+        var source = $$"""app.MapGet("/{routeValue}", ([FromRoute(Name = "invalidName" )] string parameterName) => parameterName);""";
+        var (_, compilation) = await RunGeneratorAsync(source);
+        var endpoint = GetEndpointFromCompilation(compilation);
+
+        var httpContext = CreateHttpContext();
+
+        var exception = await Assert.ThrowsAsync<InvalidOperationException>(() => endpoint.RequestDelegate(httpContext));
+        Assert.Equal("'invalidName' is not a route parameter.", exception.Message);
+    }
+}

src/Http/Http.Extensions/test/RequestDelegateGenerator/RequestDelegateGeneratorIncrementalityTests.cs renamed to src/Http/Http.Extensions/test/RequestDelegateGenerator/CompileTimeIncrementalityTests.cs

@@ -5,8 +5,10 @@
 
 namespace Microsoft.AspNetCore.Http.Generators.Tests;
 
-public class RequestDelegateGeneratorIncrementalityTests : RequestDelegateGeneratorTestBase
+public class CompileTimeIncrementalityTests : RequestDelegateGeneratorTestBase
 {
+    protected override bool IsGeneratorEnabled { get; } = true;
+
     [Fact]
     public async Task MapAction_SameReturnType_DoesNotTriggerUpdate()
     {
@@ -59,5 +61,5 @@ public async Task MapAction_ChangeBodyParamNullability_TriggersUpdate()
         Assert.All(outputSteps, (value) => Assert.Equal(IncrementalStepRunReason.New, value.Reason));
     }
 
-    private static IEnumerable<(object Value, IncrementalStepRunReason Reason)> GetRunStepOutputs(GeneratorRunResult result) => result.TrackedOutputSteps.SelectMany(step => step.Value).SelectMany(value => value.Outputs);
+    private static IEnumerable<(object Value, IncrementalStepRunReason Reason)> GetRunStepOutputs(GeneratorRunResult? result) => result?.TrackedOutputSteps.SelectMany(step => step.Value).SelectMany(value => value.Outputs);
 }

src/Http/Http.Extensions/test/RequestDelegateGenerator/RequestDelegateGeneratorTestBase.cs

@@ -23,21 +23,30 @@
 
 namespace Microsoft.AspNetCore.Http.Generators.Tests;
 
-public class RequestDelegateGeneratorTestBase : LoggedTest
+public abstract class RequestDelegateGeneratorTestBase : LoggedTest
 {
-    internal static async Task<(GeneratorRunResult, Compilation)> RunGeneratorAsync(string sources, params string[] updatedSources)
+    protected abstract bool IsGeneratorEnabled { get; }
+
+    internal async Task<(GeneratorRunResult?, Compilation)> RunGeneratorAsync(string sources, params string[] updatedSources)
     {
         var compilation = await CreateCompilationAsync(sources);
-        var generator = new RequestDelegateGenerator().AsSourceGenerator();
 
-        // Enable the source generator in tests
+        // Return the compilation immediately if
+        // the generator is not enabled.
+        if (!IsGeneratorEnabled)
+        {
+            return (null, compilation);
+        }
+
+        // Configure the generator driver and run
+        // the compilation with it if the generator
+        // is enabled.
+        var generator = new RequestDelegateGenerator().AsSourceGenerator();
         GeneratorDriver driver = CSharpGeneratorDriver.Create(generators: new[]
             {
                 generator
             },
             driverOptions: new GeneratorDriverOptions(IncrementalGeneratorOutputKind.None, trackIncrementalGeneratorSteps: true));
-
-        // Run the source generator
         driver = driver.RunGeneratorsAndUpdateCompilation(compilation, out var updatedCompilation,
             out var _);
         foreach (var updatedSource in updatedSources)
@@ -72,13 +81,30 @@ internal static StaticRouteHandlerModel.Endpoint[] GetStaticEndpoints(GeneratorR
         return Array.Empty<StaticRouteHandlerModel.Endpoint>();
     }
 
-    internal static Endpoint GetEndpointFromCompilation(Compilation compilation, bool expectSourceKey = true) =>
-        Assert.Single(GetEndpointsFromCompilation(compilation, expectSourceKey));
+    internal static void VerifyStaticEndpointModel(GeneratorRunResult? result, Action<StaticRouteHandlerModel.Endpoint> runAssertions)
+    {
+        if (result.HasValue)
+        {
+            runAssertions(GetStaticEndpoint(result.Value, GeneratorSteps.EndpointModelStep));
+        }
+    }
 
-    internal static Endpoint[] GetEndpointsFromCompilation(Compilation compilation, bool expectSourceKey = true)
+    internal static void VerifyStaticEndpointModels(GeneratorRunResult? result, Action<StaticRouteHandlerModel.Endpoint[]> runAssertions)
+    {
+        if (result.HasValue)
+        {
+            runAssertions(GetStaticEndpoints(result.Value, GeneratorSteps.EndpointModelStep));
+        }
+    }
+
+    internal Endpoint GetEndpointFromCompilation(Compilation compilation, bool? expectSourceKeyOverride = null) =>
+        Assert.Single(GetEndpointsFromCompilation(compilation, expectSourceKeyOverride));
+
+    internal Endpoint[] GetEndpointsFromCompilation(Compilation compilation, bool? expectSourceKeyOverride = null)
     {
         var assemblyName = compilation.AssemblyName!;
         var symbolsName = Path.ChangeExtension(assemblyName, "pdb");
+        var expectSourceKey = (expectSourceKeyOverride ?? true) && IsGeneratorEnabled;
 
         var output = new MemoryStream();
         var pdb = new MemoryStream();
@@ -353,6 +379,10 @@ private static Task<Compilation> CreateCompilationAsync(string sources)
 
     internal async Task VerifyAgainstBaselineUsingFile(Compilation compilation, [CallerMemberName] string callerName = "")
     {
+        if (!IsGeneratorEnabled)
+        {
+            return;
+        }
         var baselineFilePath = Path.Combine("RequestDelegateGenerator", "Baselines", $"{callerName}.generated.txt");
         var generatedSyntaxTree = compilation.SyntaxTrees.Last();
         var generatedCode = await generatedSyntaxTree.GetTextAsync();