Emit CA1822 for recursive method. (#6641)

* Emit diagnostic on recursive method. * Remove blank line.
dotnet · May 25, 2023 · 2b6ab8d · 2b6ab8d
1 parent 615f625
commit 2b6ab8d
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Showing 2 changed files with 41 additions and 1 deletion.
diff --git a/...etAnalyzers/Core/Microsoft.CodeQuality.Analyzers/QualityGuidelines/MarkMembersAsStatic.cs b/...etAnalyzers/Core/Microsoft.CodeQuality.Analyzers/QualityGuidelines/MarkMembersAsStatic.cs
@@ -104,7 +104,8 @@ void OnOperationBlockStart(OperationBlockStartAnalysisContext context)
 
                     context.RegisterOperationAction(context =>
                     {
-                        if (((IInstanceReferenceOperation)context.Operation).ReferenceKind == InstanceReferenceKind.ContainingTypeInstance)
+                        if (((IInstanceReferenceOperation)context.Operation).ReferenceKind == InstanceReferenceKind.ContainingTypeInstance
+                            && (context.Operation.Parent is not IInvocationOperation invocation || !invocation.TargetMethod.Equals(methodSymbol, SymbolEqualityComparer.Default)))
                         {
                             isInstanceReferenced = true;
                         }

diff --git a/...s/UnitTests/Microsoft.CodeQuality.Analyzers/QualityGuidelines/MarkMembersAsStaticTests.cs b/...s/UnitTests/Microsoft.CodeQuality.Analyzers/QualityGuidelines/MarkMembersAsStaticTests.cs
@@ -1461,5 +1461,44 @@ Private Sub M()
         End Sub
 End Class");
         }
+
+        [Fact, WorkItem(6540, "https://github.com/dotnet/roslyn-analyzers/issues/6540")]
+        public Task RecursiveMethod_DiagnosticAsync()
+        {
+            return new VerifyCS.Test
+            {
+                TestCode = @"
+using System;
+
+public class Test
+{
+    public void [|Recursive|](string argument)
+	{
+		if (argument.Length > 1)
+		{
+            Recursive(argument[1..]);
+		}
+
+		Console.WriteLine($""argument[-1]: {argument}"");
+    }
+}",
+                FixedCode = @"
+using System;
+
+public class Test
+{
+    public static void Recursive(string argument)
+	{
+		if (argument.Length > 1)
+		{
+            Recursive(argument[1..]);
+		}
+
+		Console.WriteLine($""argument[-1]: {argument}"");
+    }
+}",
+                LanguageVersion = LanguageVersion.CSharp8
+            }.RunAsync();
+        }
     }
 }