Merge pull request #2621 from vweijsters/fix-2594

Improved SA1132 code fix

Author: sharwell

StyleCop.Analyzers/StyleCop.Analyzers.CodeFixes/ReadabilityRules/SA1132CodeFixProvider.cs

@@ -63,7 +63,7 @@ private static async Task<Document> GetTransformedDocumentAsync(Document documen
             {
                 var editor = new SyntaxEditor(syntaxRoot, document.Project.Solution.Workspace);
                 editor.InsertAfter(baseFieldDeclaration, newFieldDeclarations);
-                editor.RemoveNode(baseFieldDeclaration);
+                editor.RemoveNode(baseFieldDeclaration, SyntaxRemoveOptions.KeepNoTrivia);
                 return document.WithSyntaxRoot(editor.GetChangedRoot().WithoutFormatting());
             }
 
@@ -118,6 +118,27 @@ private static List<BaseFieldDeclarationSyntax> DeclarationSplitter(
                     if (variable != first)
                     {
                         var triviaList = previous.GetLeadingTrivia().WithoutDirectiveTrivia();
+
+                        // Remove all leading blank lines
+                        var nonBlankLinetriviaIndex = TriviaHelper.IndexOfFirstNonBlankLineTrivia(triviaList);
+                        if (nonBlankLinetriviaIndex > 0)
+                        {
+                            triviaList = triviaList.RemoveRange(0, nonBlankLinetriviaIndex);
+                        }
+
+                        // Add a blank line if the first line contains a comment.
+                        var nonWhitespaceTriviaIndex = TriviaHelper.IndexOfFirstNonWhitespaceTrivia(triviaList, false);
+                        if (nonWhitespaceTriviaIndex >= 0)
+                        {
+                            switch (triviaList[nonWhitespaceTriviaIndex].Kind())
+                            {
+                            case SyntaxKind.SingleLineCommentTrivia:
+                            case SyntaxKind.MultiLineCommentTrivia:
+                                triviaList = triviaList.Insert(0, SyntaxFactory.CarriageReturnLineFeed);
+                                break;
+                            }
+                        }
+
                         previous = previous.WithLeadingTrivia(triviaList);
                     }
                 }

StyleCop.Analyzers/StyleCop.Analyzers.Test/ReadabilityRules/SA1132UnitTests.cs

@@ -170,6 +170,77 @@ class TestAttribute : System.Attribute
             await this.VerifyCSharpFixAsync(testCode, fixedCode).ConfigureAwait(false);
         }
 
+        [Fact]
+        [WorkItem(2594, "https://github.com/DotNetAnalyzers/StyleCopAnalyzers/issues/2594")]
+        public async Task VerifyThatDirectiveTriviaAreHandledCorrectlyAsync()
+        {
+            var testCode = @"
+namespace StyleCopDemo
+{
+    class Program
+    {
+        #region some members
+
+        string myString;
+
+        #region some fields
+
+        // this line:
+        int myInt, yourInt;
+
+        #endregion
+
+        #region some other fields
+
+        int secondInt, thirdInt;
+
+        #endregion
+
+        #endregion
+    }
+}";
+
+            var fixedCode = @"
+namespace StyleCopDemo
+{
+    class Program
+    {
+        #region some members
+
+        string myString;
+
+        #region some fields
+
+        // this line:
+        int myInt;
+
+        // this line:
+        int yourInt;
+
+        #endregion
+
+        #region some other fields
+
+        int secondInt;
+        int thirdInt;
+
+        #endregion
+
+        #endregion
+    }
+}";
+
+            DiagnosticResult[] expected =
+            {
+                this.CSharpDiagnostic().WithLocation(13, 9),
+                this.CSharpDiagnostic().WithLocation(19, 9),
+            };
+
+            await this.VerifyCSharpDiagnosticAsync(testCode, expected, CancellationToken.None).ConfigureAwait(false);
+            await this.VerifyCSharpDiagnosticAsync(fixedCode, EmptyDiagnosticResults, CancellationToken.None).ConfigureAwait(false);
+            await this.VerifyCSharpFixAsync(testCode, fixedCode).ConfigureAwait(false);
+        }
+
         protected override CodeFixProvider GetCSharpCodeFixProvider()
         {
             return new SA1132CodeFixProvider();