Update DetectPreviewFeatureAnalyzer for runtime async (#50937)

Author: 333fred

src/Microsoft.CodeAnalysis.NetAnalyzers/src/Microsoft.CodeAnalysis.CSharp.NetAnalyzers/Microsoft.NetCore.Analyzers/Runtime/CSharpDetectPreviewFeatureAnalyzer.cs

@@ -2,16 +2,30 @@
 
 using System.Collections.Immutable;
 using System.Diagnostics.CodeAnalysis;
+using Analyzer.Utilities.Lightup;
 using Microsoft.CodeAnalysis;
+using Microsoft.CodeAnalysis.CSharp;
 using Microsoft.CodeAnalysis.CSharp.Syntax;
 using Microsoft.CodeAnalysis.Diagnostics;
+using Microsoft.CodeAnalysis.Operations;
 using Microsoft.NetCore.Analyzers.Runtime;
 
 namespace Microsoft.NetCore.CSharp.Analyzers.Runtime
 {
     [DiagnosticAnalyzer(LanguageNames.CSharp)]
     public class CSharpDetectPreviewFeatureAnalyzer : DetectPreviewFeatureAnalyzer
     {
+        protected override ISymbol? SymbolFromAwaitOperation(IAwaitOperation operation)
+        {
+            if (operation.Syntax is not AwaitExpressionSyntax awaitSyntax)
+            {
+                return null;
+            }
+
+            var awaitableInfo = operation.SemanticModel.GetAwaitExpressionInfo(awaitSyntax);
+            return awaitableInfo.RuntimeAwaitMethod;
+        }
+
         protected override SyntaxNode? GetPreviewSyntaxNodeForFieldsOrEvents(ISymbol fieldOrEventSymbol, ISymbol previewSymbol)
         {
             ImmutableArray<SyntaxReference> fieldOrEventReferences = fieldOrEventSymbol.DeclaringSyntaxReferences;

src/Microsoft.CodeAnalysis.NetAnalyzers/src/Microsoft.CodeAnalysis.NetAnalyzers/Microsoft.NetCore.Analyzers/Runtime/DetectPreviewFeatureAnalyzer.cs

@@ -269,7 +269,8 @@ public override void Initialize(AnalysisContext context)
                     OperationKind.ArrayCreation,
                     OperationKind.CatchClause,
                     OperationKind.TypeOf,
-                    OperationKind.EventAssignment
+                    OperationKind.EventAssignment,
+                    OperationKind.Await
                     );
 
                 // Handle preview symbol definitions
@@ -809,7 +810,7 @@ private bool OperationUsesPreviewFeatures(OperationAnalysisContext context,
             return false;
         }
 
-        private static ISymbol? GetOperationSymbol(IOperation operation)
+        private ISymbol? GetOperationSymbol(IOperation operation)
             => operation switch
             {
                 IInvocationOperation iOperation => iOperation.TargetMethod,
@@ -824,6 +825,7 @@ private bool OperationUsesPreviewFeatures(OperationAnalysisContext context,
                 ICatchClauseOperation catchClauseOperation => catchClauseOperation.ExceptionType,
                 ITypeOfOperation typeOfOperation => typeOfOperation.TypeOperand,
                 IEventAssignmentOperation eventAssignment => GetOperationSymbol(eventAssignment.EventReference),
+                IAwaitOperation awaitOperation => SymbolFromAwaitOperation(awaitOperation),
                 _ => null,
             };
 
@@ -838,6 +840,8 @@ private bool OperationUsesPreviewFeatures(OperationAnalysisContext context,
             return ret;
         }
 
+        protected abstract ISymbol? SymbolFromAwaitOperation(IAwaitOperation operation);
+
         private bool TypeParametersHavePreviewAttribute(ISymbol namedTypeSymbolOrMethodSymbol,
                                                         ImmutableArray<ITypeParameterSymbol> typeParameters,
                                                         ConcurrentDictionary<ISymbol, (bool isPreview, string? message, string? url)> requiresPreviewFeaturesSymbols,

src/Microsoft.CodeAnalysis.NetAnalyzers/src/Microsoft.CodeAnalysis.VisualBasic.NetAnalyzers/Microsoft.NetCore.Analyzers/Runtime/BasicDetectPreviewFeatureAnalyzer.vb

@@ -2,6 +2,7 @@
 
 Imports Microsoft.CodeAnalysis
 Imports Microsoft.CodeAnalysis.Diagnostics
+Imports Microsoft.CodeAnalysis.Operations
 Imports Microsoft.NetCore.Analyzers.Runtime
 Imports Microsoft.CodeAnalysis.VisualBasic.Syntax
 
@@ -16,6 +17,10 @@ Namespace Microsoft.NetCore.VisualBasic.Analyzers.Runtime
             Return identifier.ValueText.Equals(previewInterfaceSymbol.Name, StringComparison.OrdinalIgnoreCase)
         End Function
 
+        Protected Overrides Function SymbolFromAwaitOperation(operation As IAwaitOperation) As ISymbol
+            Return Nothing
+        End Function
+
         Private Shared Function GetElementTypeForNullableAndArrayTypeNodes(parameterType As TypeSyntax) As TypeSyntax
             Dim ret As TypeSyntax = parameterType
             Dim loopVariable = TryCast(parameterType, NullableTypeSyntax)
@@ -334,4 +339,4 @@ Namespace Microsoft.NetCore.VisualBasic.Analyzers.Runtime
         End Function
     End Class
 
-End Namespace
+End Namespace

src/Microsoft.CodeAnalysis.NetAnalyzers/src/Utilities/Compiler.CSharp/Analyzer.CSharp.Utilities.projitems

@@ -10,6 +10,7 @@
   <ItemGroup>
     <Compile Include="$(MSBuildThisFileDirectory)Extensions\SyntaxGeneratorExtensions.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)Extensions\SyntaxNodeExtensions.cs" />
+    <Compile Include="$(MSBuildThisFileDirectory)Lightup\AwaitExpressionInfoWrapper.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)Lightup\SyntaxKindEx.cs" />
   </ItemGroup>
-</Project>
+</Project>

src/Microsoft.CodeAnalysis.NetAnalyzers/src/Utilities/Compiler.CSharp/Lightup/AwaitExpressionInfoWrapper.cs

@@ -0,0 +1,33 @@
+// Copyright (c) Microsoft.  All Rights Reserved.  Licensed under the MIT license.  See License.txt in the project root for license information.
+
+using Microsoft.CodeAnalysis;
+using Microsoft.CodeAnalysis.CSharp;
+
+namespace Analyzer.Utilities.Lightup
+{
+    internal static class AwaitExpressionInfoWrapper
+    {
+        private static Func<AwaitExpressionInfo, IMethodSymbol?>? s_RuntimeAwaitMethodAccessor;
+
+        extension(AwaitExpressionInfo info)
+        {
+            public IMethodSymbol? RuntimeAwaitMethod
+            {
+                get
+                {
+                    LazyInitializer.EnsureInitialized(ref s_RuntimeAwaitMethodAccessor, () =>
+                    {
+                        return LightupHelpers.CreatePropertyAccessor<AwaitExpressionInfo, IMethodSymbol?>(
+                            typeof(AwaitExpressionInfo),
+                            "info",
+                            "RuntimeAwaitMethod",
+                            fallbackResult: null);
+                    });
+
+                    RoslynDebug.Assert(s_RuntimeAwaitMethodAccessor is not null);
+                    return s_RuntimeAwaitMethodAccessor(info);
+                }
+            }
+        }
+    }
+}

src/Microsoft.CodeAnalysis.NetAnalyzers/src/Utilities/Compiler/Lightup/LightupHelpers.cs

@@ -53,7 +53,7 @@ internal static Func<TSymbol, TProperty> CreateSymbolPropertyAccessor<TSymbol, T
             where TSymbol : ISymbol
             => CreatePropertyAccessor<TSymbol, TProperty>(type, "symbol", propertyName, fallbackResult);
 
-        private static Func<T, TProperty> CreatePropertyAccessor<T, TProperty>(Type? type, string parameterName, string propertyName, TProperty fallbackResult)
+        internal static Func<T, TProperty> CreatePropertyAccessor<T, TProperty>(Type? type, string parameterName, string propertyName, TProperty fallbackResult)
         {
             if (!TryGetProperty<T, TProperty>(type, propertyName, out var property))
             {