MA0137: Add exclude_test_methods configuration option

docs/Rules/MA0137.md

@@ -12,3 +12,17 @@ Task FooAsync() => Task.CompletedTask;
 // non-compliant
 Task Foo() => Task.CompletedTask;
 ````
+
+# Configuration
+
+By default, test methods (methods decorated with test framework attributes such as `[Fact]`, `[Test]`, `[TestMethod]`, etc.) are excluded from this rule. You can change this behavior using the `.editorconfig` file:
+
+````editorconfig
+MA0137.exclude_test_methods = true # default value
+````
+
+Set to `false` to also report diagnostics on test methods:
+
+````editorconfig
+MA0137.exclude_test_methods = false
+````

src/Meziantou.Analyzer/Rules/MethodsReturningAnAwaitableTypeMustHaveTheAsyncSuffixAnalyzer.cs

@@ -1,4 +1,5 @@
 using System.Collections.Immutable;
+using Meziantou.Analyzer.Configurations;
 using Meziantou.Analyzer.Internals;
 using Microsoft.CodeAnalysis;
 using Microsoft.CodeAnalysis.Diagnostics;
@@ -81,7 +82,7 @@ public void AnalyzeSymbol(SymbolAnalysisContext context)
             if (method.IsEqualTo(context.Compilation.GetEntryPoint(context.CancellationToken)))
                 return;
 
-            if (MustIgnoreSymbol(method))
+            if (MustIgnoreSymbol(context.Options, method))
                 return;
 
             var hasAsyncSuffix = method.Name.EndsWith("Async", StringComparison.Ordinal);
@@ -145,12 +146,13 @@ public void AnalyzeLocalFunction(OperationAnalysisContext context)
             }
         }
 
-        private bool MustIgnoreSymbol(IMethodSymbol symbol)
+        private bool MustIgnoreSymbol(AnalyzerOptions options, IMethodSymbol symbol)
         {
             if (symbol.HasAttribute(_benchmarkSymbol))
                 return true;
 
-            if (symbol.IsUnitTestMethod())
+            var excludeTestMethods = options.GetConfigurationValue(symbol, "MA0137.exclude_test_methods", defaultValue: true);
+            if (excludeTestMethods && symbol.IsUnitTestMethod())
                 return true;
 
             return false;

tests/Meziantou.Analyzer.Test/Rules/MethodsReturningAnAwaitableTypeMustHaveTheAsyncSuffixAnalyzerTests.cs

@@ -170,4 +170,32 @@ class TypeName
                  """)
               .AddXUnitApi()
               .ValidateAsync();
+
+    [Fact]
+    public Task IgnoreTestMethods_ExcludeTestMethodsTrue()
+        => CreateProjectBuilder()
+              .WithSourceCode("""
+                 class TypeName
+                 {
+                     [Xunit.Fact]
+                     System.Threading.Tasks.Task Foo() => throw null;
+                 }
+                 """)
+              .AddXUnitApi()
+              .AddAnalyzerConfiguration("MA0137.exclude_test_methods", "true")
+              .ValidateAsync();
+
+    [Fact]
+    public Task IgnoreTestMethods_ExcludeTestMethodsFalse()
+        => CreateProjectBuilder()
+              .WithSourceCode("""
+                 class TypeName
+                 {
+                     [Xunit.Fact]
+                     System.Threading.Tasks.Task {|MA0137:Foo|}() => throw null;
+                 }
+                 """)
+              .AddXUnitApi()
+              .AddAnalyzerConfiguration("MA0137.exclude_test_methods", "false")
+              .ValidateAsync();
 }