Merge pull request #2896 from vweijsters/fix-2894

Fixed crash in SA1134 code fix

Author: sharwell

StyleCop.Analyzers/StyleCop.Analyzers.CodeFixes/ReadabilityRules/SA1134CodeFixProvider.cs

@@ -33,19 +33,23 @@ public override FixAllProvider GetFixAllProvider()
         }
 
         /// <inheritdoc/>
-        public override Task RegisterCodeFixesAsync(CodeFixContext context)
+        public override async Task RegisterCodeFixesAsync(CodeFixContext context)
         {
+            var syntaxRoot = await context.Document.GetSyntaxRootAsync(context.CancellationToken).ConfigureAwait(false);
+
             foreach (var diagnostic in context.Diagnostics)
             {
-                context.RegisterCodeFix(
-                    CodeAction.Create(
-                        ReadabilityResources.SA1134CodeFix,
-                        cancellationToken => GetTransformedDocumentAsync(context.Document, diagnostic, cancellationToken),
-                        nameof(SA1134CodeFixProvider)),
-                    diagnostic);
+                // Do not offer the code fix if the error is found at an invalid node (like IncompleteMemberSyntax)
+                if (syntaxRoot.FindNode(diagnostic.Location.SourceSpan) is AttributeListSyntax)
+                {
+                    context.RegisterCodeFix(
+                        CodeAction.Create(
+                            ReadabilityResources.SA1134CodeFix,
+                            cancellationToken => GetTransformedDocumentAsync(context.Document, diagnostic, cancellationToken),
+                            nameof(SA1134CodeFixProvider)),
+                        diagnostic);
+                }
             }
-
-            return SpecializedTasks.CompletedTask;
         }
 
         private static async Task<Document> GetTransformedDocumentAsync(Document document, Diagnostic diagnostic, CancellationToken cancellationToken)

StyleCop.Analyzers/StyleCop.Analyzers.Test/ReadabilityRules/SA1134UnitTests.cs

@@ -409,5 +409,35 @@ public class TestClass<[Test(""Test1"")][Test(""Test2"")]T>
 
             await VerifyCSharpDiagnosticAsync(testCode, DiagnosticResult.EmptyDiagnosticResults, CancellationToken.None).ConfigureAwait(false);
         }
+
+        /// <summary>
+        /// Verifies that passing an invalid member syntax into the codefix will not change the code.
+        /// </summary>
+        /// <returns>A <see cref="Task"/> representing the asynchronous unit test.</returns>
+        [Fact]
+        [WorkItem(2894, "https://github.com/DotNetAnalyzers/StyleCopAnalyzers/issues/2894")]
+        public async Task VerifyInvalidMemberSyntaxInCodeFixAsync()
+        {
+            string testCode = @"class Program
+{
+    static void Main(string[] args)
+    {
+        {
+        }[;]
+    }
+}
+";
+
+            DiagnosticResult[] expected =
+            {
+                DiagnosticResult.CompilerError("CS1513").WithLocation(6, 10),
+                Diagnostic().WithLocation(6, 10),
+                DiagnosticResult.CompilerError("CS1001").WithLocation(6, 11),
+                DiagnosticResult.CompilerError("CS1001").WithLocation(6, 11),
+                DiagnosticResult.CompilerError("CS1022").WithLocation(8, 1),
+            };
+
+            await VerifyCSharpFixAsync(testCode, expected, testCode, CancellationToken.None).ConfigureAwait(false);
+        }
     }
 }