Add support for skipping analyzing banned API analysis in generated files

src/RoslynAnalyzers/Microsoft.CodeAnalysis.Analyzers/CSharp/MetaAnalyzers/CSharpSymbolIsBannedInAnalyzersAnalyzer.cs

@@ -23,5 +23,8 @@ public sealed class CSharpSymbolIsBannedInAnalyzersAnalyzer : SymbolIsBannedInAn
         protected override SyntaxNode GetReferenceSyntaxNodeFromXmlCref(SyntaxNode syntaxNode) => ((XmlCrefAttributeSyntax)syntaxNode).Cref;
 
         protected override IEnumerable<SyntaxNode> GetTypeSyntaxNodesFromBaseType(SyntaxNode syntaxNode) => ((BaseListSyntax)syntaxNode).Types.Select(t => (SyntaxNode)t.Type);
+
+        protected override bool IsRegularCommentOrDocumentationComment(SyntaxTrivia trivia)
+            => trivia.Kind() is SyntaxKind.SingleLineCommentTrivia or SyntaxKind.MultiLineCommentTrivia or SyntaxKind.ShebangDirectiveTrivia or SyntaxKind.SingleLineDocumentationCommentTrivia or SyntaxKind.MultiLineDocumentationCommentTrivia;
     }
 }

src/RoslynAnalyzers/Microsoft.CodeAnalysis.Analyzers/VisualBasic/BasicSymbolIsBannedInAnalyzersAnalyzer.vb

@@ -44,5 +44,9 @@ Namespace Microsoft.CodeAnalysis.VisualBasic.Analyzers
             End If
         End Function
 
+        Protected Overrides Function IsRegularCommentOrDocumentationComment(trivia As SyntaxTrivia) As Boolean
+            Return trivia.Kind() = SyntaxKind.CommentTrivia OrElse trivia.Kind() = SyntaxKind.DocumentationCommentTrivia
+        End Function
+
     End Class
 End Namespace

src/RoslynAnalyzers/Microsoft.CodeAnalysis.BannedApiAnalyzers/BannedApiAnalyzers.Help.md

@@ -16,6 +16,14 @@ This can be done by:
   </ItemGroup>
   ```
 
+Generated code is analyzed by default. To exclude generated code from banned API analysis, add the following to an analyzer config file such as `.globalconfig`:
+
+```ini
+is_global = true
+
+banned_api_analyzer.exclude_generated_code = true
+```
+
 To add a symbol to the banned list, just add an entry in the format below to one of the configuration files (Description Text will be displayed as description in diagnostics, which is optional):
 
 ```txt

src/RoslynAnalyzers/Microsoft.CodeAnalysis.BannedApiAnalyzers/CSharp/CSharpSymbolIsBannedAnalyzer.cs

@@ -20,6 +20,9 @@ public sealed class CSharpSymbolIsBannedAnalyzer : SymbolIsBannedAnalyzer<Syntax
 
         protected override SymbolDisplayFormat SymbolDisplayFormat => SymbolDisplayFormat.CSharpShortErrorMessageFormat;
 
+        protected override bool IsRegularCommentOrDocumentationComment(SyntaxTrivia trivia)
+            => trivia.Kind() is SyntaxKind.SingleLineCommentTrivia or SyntaxKind.MultiLineCommentTrivia or SyntaxKind.ShebangDirectiveTrivia or SyntaxKind.SingleLineDocumentationCommentTrivia or SyntaxKind.MultiLineDocumentationCommentTrivia;
+
         protected override SyntaxNode GetReferenceSyntaxNodeFromXmlCref(SyntaxNode syntaxNode) => ((XmlCrefAttributeSyntax)syntaxNode).Cref;
 
         protected override IEnumerable<SyntaxNode> GetTypeSyntaxNodesFromBaseType(SyntaxNode syntaxNode) => ((BaseListSyntax)syntaxNode).Types.Select(t => (SyntaxNode)t.Type);

src/RoslynAnalyzers/Microsoft.CodeAnalysis.BannedApiAnalyzers/Core/SymbolIsBannedAnalyzerBase.cs

@@ -3,6 +3,7 @@
 // See the LICENSE file in the project root for more information.
 
 using System;
+using System.Collections.Concurrent;
 using System.Collections.Generic;
 using System.Collections.Immutable;
 using System.Diagnostics.CodeAnalysis;
@@ -13,12 +14,15 @@
 using Microsoft.CodeAnalysis.Operations;
 using Microsoft.CodeAnalysis.Shared.Extensions;
 using Microsoft.CodeAnalysis.Text;
+using Roslyn.Utilities;
 
 namespace Microsoft.CodeAnalysis.BannedApiAnalyzers
 {
     public abstract class SymbolIsBannedAnalyzerBase<TSyntaxKind> : DiagnosticAnalyzer
         where TSyntaxKind : struct
     {
+        private const string ExcludeGeneratedCodeOptionName = "banned_api_analyzer.exclude_generated_code";
+
         protected abstract Dictionary<(string ContainerName, string SymbolName), ImmutableArray<BanFileEntry>>? ReadBannedApis(CompilationStartAnalysisContext compilationContext);
 
         protected abstract DiagnosticDescriptor SymbolIsBannedRule { get; }
@@ -33,6 +37,8 @@ public abstract class SymbolIsBannedAnalyzerBase<TSyntaxKind> : DiagnosticAnalyz
 
         protected abstract SymbolDisplayFormat SymbolDisplayFormat { get; }
 
+        protected abstract bool IsRegularCommentOrDocumentationComment(SyntaxTrivia trivia);
+
         public override void Initialize(AnalysisContext context)
         {
             context.EnableConcurrentExecution();
@@ -49,6 +55,8 @@ private void OnCompilationStart(CompilationStartAnalysisContext compilationConte
             if (bannedApis == null || bannedApis.Count == 0)
                 return;
 
+            var excludeGeneratedCodeMap = new ConcurrentDictionary<SyntaxTree, bool>();
+
             if (ShouldAnalyzeAttributes())
             {
                 compilationContext.RegisterCompilationEndAction(
@@ -59,7 +67,10 @@ private void OnCompilationStart(CompilationStartAnalysisContext compilationConte
                     });
 
                 compilationContext.RegisterSymbolAction(
-                    context => VerifyAttributes(context.ReportDiagnostic, context.Symbol.GetAttributes(), context.CancellationToken),
+                    context =>
+                    {
+                        VerifyAttributes(context.ReportDiagnostic, context.Symbol.GetAttributes(), context.CancellationToken);
+                    },
                     SymbolKind.NamedType,
                     SymbolKind.Method,
                     SymbolKind.Field,
@@ -71,6 +82,9 @@ private void OnCompilationStart(CompilationStartAnalysisContext compilationConte
                 context =>
                 {
                     context.CancellationToken.ThrowIfCancellationRequested();
+                    if (ShouldSkipOperationAnalysis(context))
+                        return;
+
                     switch (context.Operation)
                     {
                         case IObjectCreationOperation objectCreation:
@@ -153,11 +167,23 @@ private void OnCompilationStart(CompilationStartAnalysisContext compilationConte
                 OperationKind.TypeOf);
 
             compilationContext.RegisterSyntaxNodeAction(
-                context => VerifyDocumentationSyntax(context.ReportDiagnostic, GetReferenceSyntaxNodeFromXmlCref(context.Node), context),
+                context =>
+                {
+                    if (ShouldSkipSyntaxNodeAnalysis(context))
+                        return;
+
+                    VerifyDocumentationSyntax(context.ReportDiagnostic, GetReferenceSyntaxNodeFromXmlCref(context.Node), context);
+                },
                 XmlCrefSyntaxKind);
 
             compilationContext.RegisterSyntaxNodeAction(
-                context => VerifyBaseTypesSyntax(context.ReportDiagnostic, GetTypeSyntaxNodesFromBaseType(context.Node), context),
+                context =>
+                {
+                    if (ShouldSkipSyntaxNodeAnalysis(context))
+                        return;
+
+                    VerifyBaseTypesSyntax(context.ReportDiagnostic, GetTypeSyntaxNodesFromBaseType(context.Node), context);
+                },
                 BaseTypeSyntaxKinds);
 
             return;
@@ -219,32 +245,55 @@ bool ContainsAttributeSymbol(ISymbol symbol)
                 };
             }
 
+            bool ShouldSkipOperationAnalysis(OperationAnalysisContext context)
+                => context.IsGeneratedCode && ExcludesGeneratedCode(context.Operation.Syntax.SyntaxTree);
+
+            bool ShouldSkipSyntaxNodeAnalysis(SyntaxNodeAnalysisContext context)
+                => context.IsGeneratedCode && ExcludesGeneratedCode(context.Node.SyntaxTree);
+
+            bool ShouldSkipTreeAnalysis(SyntaxTree tree, CancellationToken cancellationToken)
+                => ExcludesGeneratedCode(tree) && IsGeneratedCode(tree, cancellationToken);
+
+            bool ExcludesGeneratedCode(SyntaxTree tree)
+                => excludeGeneratedCodeMap.GetOrAdd(
+                    tree,
+                    tree =>
+                    {
+                        var options = compilationContext.Options.AnalyzerConfigOptionsProvider.GetOptions(tree);
+                        return options.TryGetValue(ExcludeGeneratedCodeOptionName, out var optionValue) &&
+                            bool.TryParse(optionValue, out var excludeGeneratedCode) &&
+                            excludeGeneratedCode;
+                    });
+
+            bool IsGeneratedCode(SyntaxTree tree, CancellationToken cancellationToken)
+                => GeneratedCodeUtilities.GetGeneratedCodeKindFromOptions(compilationContext.Options.AnalyzerConfigOptionsProvider.GetOptions(tree)).ToNullable() ??
+                   GeneratedCodeUtilities.IsGeneratedCode(tree, IsRegularCommentOrDocumentationComment, cancellationToken);
+
             void VerifyAttributes(Action<Diagnostic> reportDiagnostic, ImmutableArray<AttributeData> attributes, CancellationToken cancellationToken)
             {
                 cancellationToken.ThrowIfCancellationRequested();
                 foreach (var attribute in attributes)
                 {
+                    var applicationSyntaxReference = attribute.ApplicationSyntaxReference;
+                    if (applicationSyntaxReference == null)
+                        continue;
+
+                    var node = applicationSyntaxReference.GetSyntax(cancellationToken);
+                    if (ShouldSkipTreeAnalysis(node.SyntaxTree, cancellationToken))
+                        continue;
+
                     if (IsBannedSymbol(attribute.AttributeClass, out var entry))
                     {
-                        var node = attribute.ApplicationSyntaxReference?.GetSyntax(cancellationToken);
-                        if (node != null)
-                        {
-                            reportDiagnostic(
-                                node.CreateDiagnostic(
-                                    SymbolIsBannedRule,
-                                    attribute.AttributeClass.ToDisplayString(),
-                                    string.IsNullOrWhiteSpace(entry.Message) ? "" : ": " + entry.Message));
-                        }
+                        reportDiagnostic(
+                            node.CreateDiagnostic(
+                                SymbolIsBannedRule,
+                                attribute.AttributeClass.ToDisplayString(),
+                                string.IsNullOrWhiteSpace(entry.Message) ? "" : ": " + entry.Message));
                     }
 
                     if (attribute.AttributeConstructor != null)
                     {
-                        var syntaxNode = attribute.ApplicationSyntaxReference?.GetSyntax(cancellationToken);
-
-                        if (syntaxNode != null)
-                        {
-                            VerifySymbol(reportDiagnostic, attribute.AttributeConstructor, syntaxNode);
-                        }
+                        VerifySymbol(reportDiagnostic, attribute.AttributeConstructor, node);
                     }
                 }
             }