Improved test coverage for edge cases

Author: sharwell

DocumentationAnalyzers/DocumentationAnalyzers.CodeFixes/StyleRules/DOC103CodeFixProvider.cs

@@ -26,24 +26,31 @@ internal class DOC103CodeFixProvider : CodeFixProvider
         public override FixAllProvider GetFixAllProvider()
             => CustomFixAllProviders.BatchFixer;
 
-        public override Task RegisterCodeFixesAsync(CodeFixContext context)
+        public override async Task RegisterCodeFixesAsync(CodeFixContext context)
         {
+            SyntaxNode root = await context.Document.GetSyntaxRootAsync(context.CancellationToken).ConfigureAwait(false);
+
             foreach (var diagnostic in context.Diagnostics)
             {
                 if (!FixableDiagnosticIds.Contains(diagnostic.Id))
                 {
                     continue;
                 }
 
+                SyntaxToken token = root.FindToken(diagnostic.Location.SourceSpan.Start, findInsideTrivia: true);
+                if (!token.IsKind(SyntaxKind.XmlEntityLiteralToken))
+                {
+                    // Could be an unrelated CS1570 error.
+                    return;
+                }
+
                 context.RegisterCodeFix(
                     CodeAction.Create(
                         StyleResources.DOC103CodeFix,
-                        token => GetTransformedDocumentAsync(context.Document, diagnostic, token),
+                        cancellationToken => GetTransformedDocumentAsync(context.Document, diagnostic, cancellationToken),
                         nameof(DOC103CodeFixProvider)),
                     diagnostic);
             }
-
-            return SpecializedTasks.CompletedTask;
         }
 
         private static async Task<Document> GetTransformedDocumentAsync(Document document, Diagnostic diagnostic, CancellationToken cancellationToken)

DocumentationAnalyzers/DocumentationAnalyzers.Test/StyleRules/DOC103UnitTests.cs

@@ -110,5 +110,105 @@ class TestClass
                 CompilerDiagnostics = CompilerDiagnostics.Warnings,
             }.RunAsync();
         }
+
+        [Fact]
+        public async Task TestHtmlEntityReplacementInInvalidXmlAsync()
+        {
+            var testCode = @"
+/// <summary>
+/// From A&rarr;B.
+/// <p>
+/// An unterminated second paragraph...
+/// </summary>
+class TestClass
+{
+}
+";
+            var fixedCode = @"
+/// <summary>
+/// From A→B.
+/// <p>
+/// An unterminated second paragraph...
+/// </summary>
+class TestClass
+{
+}
+";
+
+            await new CSharpCodeFixTest<DOC103UseUnicodeCharacters, DOC103CodeFixProvider, XUnitVerifier>
+            {
+                TestState =
+                {
+                    Sources = { testCode },
+                    ExpectedDiagnostics =
+                    {
+                        DiagnosticResult.CompilerWarning("CS1570").WithSpan(3, 11, 3, 11).WithMessage("XML comment has badly formed XML -- 'Reference to undefined entity 'rarr'.'"),
+                        DiagnosticResult.CompilerWarning("CS1570").WithSpan(6, 7, 6, 14).WithMessage("XML comment has badly formed XML -- 'End tag 'summary' does not match the start tag 'p'.'"),
+                        DiagnosticResult.CompilerWarning("CS1570").WithSpan(7, 1, 7, 1).WithMessage("XML comment has badly formed XML -- 'Expected an end tag for element 'summary'.'"),
+                    },
+                },
+                FixedState =
+                {
+                    Sources = { fixedCode },
+                    ExpectedDiagnostics =
+                    {
+                        DiagnosticResult.CompilerWarning("CS1570").WithSpan(6, 7, 6, 14).WithMessage("XML comment has badly formed XML -- 'End tag 'summary' does not match the start tag 'p'.'"),
+                        DiagnosticResult.CompilerWarning("CS1570").WithSpan(7, 1, 7, 1).WithMessage("XML comment has badly formed XML -- 'Expected an end tag for element 'summary'.'"),
+                    },
+                },
+                CompilerDiagnostics = CompilerDiagnostics.Warnings,
+            }.RunAsync();
+        }
+
+        [Fact]
+        public async Task TestNoCodeFixForRequiredEntityAsync()
+        {
+            var testCode = @"
+/// <summary>
+/// Processing for <c>&lt;code&gt;</c> elements.
+/// </summary>
+class TestClass
+{
+}
+";
+            var fixedCode = testCode;
+
+            await Verify.VerifyCodeFixAsync(testCode, fixedCode);
+        }
+
+        [Fact]
+        public async Task TestNoCodeFixForInvalidXmlAsync()
+        {
+            var testCode = @"
+/// <summary>
+/// From A to B.
+/// <p>
+/// An unterminated second paragraph...
+/// </summary>
+class TestClass
+{
+}
+";
+            var fixedCode = testCode;
+
+            await new CSharpCodeFixTest<DOC103UseUnicodeCharacters, DOC103CodeFixProvider, XUnitVerifier>
+            {
+                TestState =
+                {
+                    Sources = { testCode },
+                    ExpectedDiagnostics =
+                    {
+                        DiagnosticResult.CompilerWarning("CS1570").WithSpan(6, 7, 6, 14).WithMessage("XML comment has badly formed XML -- 'End tag 'summary' does not match the start tag 'p'.'"),
+                        DiagnosticResult.CompilerWarning("CS1570").WithSpan(7, 1, 7, 1).WithMessage("XML comment has badly formed XML -- 'Expected an end tag for element 'summary'.'"),
+                    },
+                },
+                FixedState =
+                {
+                    Sources = { fixedCode },
+                    InheritanceMode = StateInheritanceMode.AutoInheritAll,
+                },
+                CompilerDiagnostics = CompilerDiagnostics.Warnings,
+            }.RunAsync();
+        }
     }
 }