Merge pull request #6343 from Youssef1313/multiple-enumeration-simplify

Simplify multiple enumeration analyzer

Author: mavasani

src/NetAnalyzers/CSharp/Microsoft.CodeQuality.Analyzers/QualityGuidelines/CSharpAvoidMultipleEnumerationsAnalyzer.DataFlowOperationVisitor.cs

@@ -1,19 +1,15 @@
 // Copyright (c) Microsoft.  All Rights Reserved.  Licensed under the MIT license.  See License.txt in the project root for license information.
 
+using Microsoft.CodeAnalysis.CSharp.Syntax;
 using Microsoft.CodeAnalysis.Diagnostics;
 using Microsoft.CodeQuality.Analyzers.QualityGuidelines.AvoidMultipleEnumerations;
-using Microsoft.CodeQuality.Analyzers.QualityGuidelines.AvoidMultipleEnumerations.FlowAnalysis;
 
 namespace Microsoft.CodeAnalysis.CSharp.NetAnalyzers.Microsoft.CodeQuality.Analyzers.QualityGuidelines
 {
     [DiagnosticAnalyzer(LanguageNames.CSharp)]
     internal sealed partial class CSharpAvoidMultipleEnumerationsAnalyzer : AvoidMultipleEnumerations
     {
-        protected override GlobalFlowStateDictionaryFlowOperationVisitor CreateOperationVisitor(
-            GlobalFlowStateDictionaryAnalysisContext context,
-            WellKnownSymbolsInfo wellKnownSymbolsInfo)
-            => new CSharpInvocationCountValueSetFlowStateDictionaryFlowOperationVisitor(
-                context,
-                wellKnownSymbolsInfo);
+        protected override bool IsExpressionOfForEachStatement(SyntaxNode node)
+            => node.Parent is ForEachStatementSyntax forEachStatementSyntax && forEachStatementSyntax.Expression.Equals(node);
     }
 }

src/NetAnalyzers/CSharp/Microsoft.CodeQuality.Analyzers/QualityGuidelines/CSharpAvoidMultipleEnumerationsAnalyzer.cs

@@ -15,19 +15,20 @@ namespace Microsoft.CodeQuality.Analyzers.QualityGuidelines.AvoidMultipleEnumera
 {
     internal partial class AvoidMultipleEnumerations
     {
-        internal abstract class AvoidMultipleEnumerationsFlowStateDictionaryFlowOperationVisitor : GlobalFlowStateDictionaryFlowOperationVisitor
+        internal sealed class AvoidMultipleEnumerationsFlowStateDictionaryFlowOperationVisitor : GlobalFlowStateDictionaryFlowOperationVisitor
         {
+            private readonly AvoidMultipleEnumerations _analyzer;
             private readonly WellKnownSymbolsInfo _wellKnownSymbolsInfo;
 
-            protected AvoidMultipleEnumerationsFlowStateDictionaryFlowOperationVisitor(
+            internal AvoidMultipleEnumerationsFlowStateDictionaryFlowOperationVisitor(
+                AvoidMultipleEnumerations analyzer,
                 GlobalFlowStateDictionaryAnalysisContext analysisContext,
                 WellKnownSymbolsInfo wellKnownSymbolsInfo) : base(analysisContext)
             {
+                _analyzer = analyzer;
                 _wellKnownSymbolsInfo = wellKnownSymbolsInfo;
             }
 
-            protected abstract bool IsExpressionOfForEachStatement(SyntaxNode node);
-
             public override GlobalFlowStateDictionaryAnalysisValue VisitParameterReference(IParameterReferenceOperation operation, object? argument)
             {
                 var value = base.VisitParameterReference(operation, argument);
@@ -361,7 +362,7 @@ private bool IsGetEnumeratorOfForEachLoopInvoked(IOperation operation)
                 // because the Operation in CFG doesn't have that information. (CFG will convert the for each operation to control flow blocks)
                 return operation.Parent is IInvocationOperation invocationOperation
                    && _wellKnownSymbolsInfo.GetEnumeratorMethods.Contains(invocationOperation.TargetMethod.OriginalDefinition)
-                   && IsExpressionOfForEachStatement(invocationOperation.Syntax);
+                   && _analyzer.IsExpressionOfForEachStatement(invocationOperation.Syntax);
             }
         }
     }

src/NetAnalyzers/Core/Microsoft.CodeQuality.Analyzers/QualityGuidelines/AvoidMultipleEnumerations/AvoidMultipleEnumerations.DataFlowOperationVisitor.cs

@@ -150,9 +150,7 @@ internal abstract partial class AvoidMultipleEnumerations : DiagnosticAnalyzer
             // Only available on .net6 or later
             "TryGetNonEnumeratedCount");
 
-        protected abstract GlobalFlowStateDictionaryFlowOperationVisitor CreateOperationVisitor(
-            GlobalFlowStateDictionaryAnalysisContext context,
-            WellKnownSymbolsInfo wellKnownSymbolsInfo);
+        protected abstract bool IsExpressionOfForEachStatement(SyntaxNode syntax);
 
         public override void Initialize(AnalysisContext context)
         {
@@ -300,7 +298,8 @@ private void Analyze(
                 var analysisResult = GlobalFlowStateDictionaryAnalysis.TryGetOrComputeResult(
                     cfg,
                     context.OwningSymbol,
-                    analysisContext => CreateOperationVisitor(
+                    analysisContext => new AvoidMultipleEnumerationsFlowStateDictionaryFlowOperationVisitor(
+                        this,
                         analysisContext,
                         wellKnownSymbolsInfo),
                     wellKnownTypeProvider,

src/NetAnalyzers/Core/Microsoft.CodeQuality.Analyzers/QualityGuidelines/AvoidMultipleEnumerations/AvoidMultipleEnumerations.cs

@@ -2,17 +2,18 @@
 
 Imports Microsoft.CodeAnalysis
 Imports Microsoft.CodeAnalysis.Diagnostics
+Imports Microsoft.CodeAnalysis.VisualBasic.Syntax
 Imports Microsoft.CodeQuality.Analyzers.QualityGuidelines.AvoidMultipleEnumerations
-Imports Microsoft.CodeQuality.Analyzers.QualityGuidelines.AvoidMultipleEnumerations.FlowAnalysis
 
 Namespace Microsoft.CodeQuality.VisualBasic.Analyzers.QualityGuidelines
 
     <DiagnosticAnalyzer(LanguageNames.VisualBasic)>
     Partial Friend NotInheritable Class BasicAvoidMultipleEnumerationsAnalyzer
         Inherits AvoidMultipleEnumerations
 
-        Protected Overrides Function CreateOperationVisitor(context As GlobalFlowStateDictionaryAnalysisContext, wellKnownSymbolsInfo As WellKnownSymbolsInfo) As GlobalFlowStateDictionaryFlowOperationVisitor
-            Return New BasicInvocationCountDataFlowOperationVisitor(context, wellKnownSymbolsInfo)
+        Protected Overrides Function IsExpressionOfForEachStatement(node As SyntaxNode) As Boolean
+            Dim parent = TryCast(node.Parent, ForEachStatementSyntax)
+            Return parent IsNot Nothing AndAlso parent.Expression.Equals(node)
         End Function
     End Class
 End Namespace