Fix invalid cast in SA1313

Fixes DotNetAnalyzers#1442
sharwell · Sep 10, 2015 · b1c8eac · b1c8eac
1 parent 526ebb0
commit b1c8eac
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Showing 2 changed files with 28 additions and 1 deletion.
diff --git a/StyleCop.Analyzers/StyleCop.Analyzers.Test/NamingRules/SA1313UnitTests.cs b/StyleCop.Analyzers/StyleCop.Analyzers.Test/NamingRules/SA1313UnitTests.cs
@@ -362,6 +362,27 @@ public override void Method(int Param1, int param2, int Other)
             await this.VerifyCSharpDiagnosticAsync(testCode, expected, CancellationToken.None).ConfigureAwait(false);
         }
 
+        /// <summary>
+        /// This is a regression test for DotNetAnalyzers/StyleCopAnalyzers#1442:
+        /// https://github.com/DotNetAnalyzers/StyleCopAnalyzers/issues/1442
+        /// </summary>
+        /// <returns>A <see cref="Task"/> representing the asynchronous operation.</returns>
+        [Fact]
+        public async Task TestSimpleLambaExpressionAsync()
+        {
+            var testCode = @"public class TypeName
+{
+    public void MethodName()
+    {
+        System.Action<int> action = Ignored => { };
+    }
+}";
+
+            DiagnosticResult expected = this.CSharpDiagnostic().WithArguments("Ignored").WithLocation(5, 37);
+
+            await this.VerifyCSharpDiagnosticAsync(testCode, expected, CancellationToken.None).ConfigureAwait(false);
+        }
+
         protected override IEnumerable<DiagnosticAnalyzer> GetCSharpDiagnosticAnalyzers()
         {
             yield return new SA1313ParameterNamesMustBeginWithLowerCaseLetter();

diff --git a/...lyzers/StyleCop.Analyzers/NamingRules/SA1313ParameterNamesMustBeginWithLowerCaseLetter.cs b/...lyzers/StyleCop.Analyzers/NamingRules/SA1313ParameterNamesMustBeginWithLowerCaseLetter.cs
@@ -91,7 +91,13 @@ private static void HandleParameterSyntax(SyntaxNodeAnalysisContext context)
 
         private static bool NameMatchesAbstraction(ParameterSyntax syntax, SemanticModel semanticModel)
         {
-            var parameterList = (ParameterListSyntax)syntax.Parent;
+            var parameterList = syntax.Parent as ParameterListSyntax;
+            if (parameterList == null)
+            {
+                // This occurs for simple lambda expressions (without parentheses)
+                return false;
+            }
+
             var index = parameterList.Parameters.IndexOf(syntax);
             var declaringMember = syntax.Parent.Parent;