Reproducer for #8988 S1172 FP: Don't report on partial method parameters

analyzers/tests/SonarAnalyzer.Test/Rules/MethodParameterUnusedTest.cs

@@ -94,9 +94,33 @@ public void MethodParameterUnused_CSharp10_RoslynCfg() =>
 
         [TestMethod]
         public void MethodParameterUnused_CSharp11_CS() =>
-                 roslynCS
-                    .AddPaths("MethodParameterUnused.CSharp11.cs")
-                    .WithOptions(ParseOptionsHelper.FromCSharp11)
-                    .Verify();
+            roslynCS.AddPaths("MethodParameterUnused.CSharp11.cs")
+                .WithOptions(ParseOptionsHelper.FromCSharp11)
+                .Verify();
+
+        [TestMethod]
+        public void MethodParameterUnused_GeneratedCode_CS() =>
+            roslynCS.AddSnippet("""
+                using System.CodeDom.Compiler;
+
+                [GeneratedCode("TestTool", "Version")]
+                public partial class Generated
+                {
+                    private partial void M(int a, int unused);
+                }             
+                """)
+            .AddSnippet("""
+                using System;
+
+                public partial class Generated
+                {
+                    private partial void M(int a, int unused) // Noncompliant FP
+                    {
+                        Console.WriteLine(a);
+                    }
+                }
+                """)
+            .WithOptions(ParseOptionsHelper.FromCSharp9)
+            .Verify();
     }
 }

analyzers/tests/SonarAnalyzer.Test/TestCases/MethodParameterUnused.CSharp11.cs

@@ -30,3 +30,19 @@ private void Argument_UsedInGenericAttributeByNameOf<TArgument>(TArgument argume
     }
 }
 
+namespace Issue_8988
+{
+    public partial class PartialMethod
+    {
+        private partial string ExtendedPartialMethod(string one, string two);
+    }
+
+    public partial class PartialMethod
+    {
+        private partial string ExtendedPartialMethod(string one, string two) // Noncompliant FP
+        {
+            return two;
+        }
+    }
+}
+

analyzers/tests/SonarAnalyzer.Test/TestCases/MethodParameterUnused.RoslynCfg.Fixed.cs

@@ -344,6 +344,19 @@ partial class MethodAssignedToActionFromPartialClass
         public System.Action<int> MyReference = MethodAssignedToActionFromPartialClass.MyMethod5;
     }
 
+    public partial class PartialMethod
+    {
+        partial void FalsePositive(string one, string two);
+    }
+
+    public partial class PartialMethod
+    {
+        partial void FalsePositive(string two) // Fixed
+        {
+            Console.Write(two);
+        }
+    }
+
     public class Dead
     {
         private int Method1(int p) => (new Func<int>(() => { p = 10; return p; }))(); // Not reporting on this

analyzers/tests/SonarAnalyzer.Test/TestCases/MethodParameterUnused.RoslynCfg.cs

@@ -346,6 +346,19 @@ partial class MethodAssignedToActionFromPartialClass
         public System.Action<int> MyReference = MethodAssignedToActionFromPartialClass.MyMethod5;
     }
 
+    public partial class PartialMethod
+    {
+        partial void FalsePositive(string one, string two);
+    }
+
+    public partial class PartialMethod
+    {
+        partial void FalsePositive(string one, string two) // Noncompliant FP
+        {
+            Console.Write(two);
+        }
+    }
+
     public class Dead
     {
         private int Method1(int p) => (new Func<int>(() => { p = 10; return p; }))(); // Not reporting on this