Disable MA0141/MA0142/MA0148/MA0149 in System.Linq.Expression

meziantou · Jan 27, 2024 · 8e82029 · 8e82029
1 parent 21e8a55
commit 8e82029
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Showing 2 changed files with 41 additions and 15 deletions.
diff --git a/src/Meziantou.Analyzer/Rules/UsePatternMatchingForEqualityComparisonsAnalyzer.cs b/src/Meziantou.Analyzer/Rules/UsePatternMatchingForEqualityComparisonsAnalyzer.cs
@@ -65,30 +65,43 @@ public override void Initialize(AnalysisContext context)
             if (tree.GetCSharpLanguageVersion() < Microsoft.CodeAnalysis.CSharp.LanguageVersion.CSharp8)
                 return;
 
-            context.RegisterOperationAction(AnalyzeBinary, OperationKind.Binary);
+            var analyzerContext = new AnalyzerContext(context.Compilation);
+            context.RegisterOperationAction(analyzerContext.AnalyzeBinary, OperationKind.Binary);
         });
     }
 
-    private static void AnalyzeBinary(OperationAnalysisContext context)
+    private sealed class AnalyzerContext(Compilation compilation)
     {
-        var operation = (IBinaryOperation)context.Operation;
-        if (operation is { OperatorKind: BinaryOperatorKind.Equals or BinaryOperatorKind.NotEquals, OperatorMethod: null })
+        private readonly OperationUtilities _operationUtilities = new(compilation);
+
+        public void AnalyzeBinary(OperationAnalysisContext context)
         {
-            var leftIsNull = UsePatternMatchingForEqualityComparisonsCommon.IsNull(operation.LeftOperand);
-            var rightIsNull = UsePatternMatchingForEqualityComparisonsCommon.IsNull(operation.RightOperand);
-            if (leftIsNull ^ rightIsNull)
-            {
-                context.ReportDiagnostic(operation.OperatorKind is BinaryOperatorKind.Equals ? RuleEqualNull : RuleNotEqualNull, operation);
-            }
-            else if (!leftIsNull && !rightIsNull)
+            var operation = (IBinaryOperation)context.Operation;
+            if (operation is { OperatorKind: BinaryOperatorKind.Equals or BinaryOperatorKind.NotEquals, OperatorMethod: null })
             {
-                var leftIsConstant = UsePatternMatchingForEqualityComparisonsCommon.IsConstantLiteral(operation.LeftOperand);
-                var rightIsConstant = UsePatternMatchingForEqualityComparisonsCommon.IsConstantLiteral(operation.RightOperand);
-                if (leftIsConstant ^ rightIsConstant)
+                var leftIsNull = UsePatternMatchingForEqualityComparisonsCommon.IsNull(operation.LeftOperand);
+                var rightIsNull = UsePatternMatchingForEqualityComparisonsCommon.IsNull(operation.RightOperand);
+                if (leftIsNull ^ rightIsNull)
+                {
+                    if (_operationUtilities.IsInExpressionContext(operation))
+                        return;
+
+                    context.ReportDiagnostic(operation.OperatorKind is BinaryOperatorKind.Equals ? RuleEqualNull : RuleNotEqualNull, operation);
+                }
+                else if (!leftIsNull && !rightIsNull)
                 {
-                    context.ReportDiagnostic(operation.OperatorKind is BinaryOperatorKind.Equals ? RuleEqualConstant : RuleNotEqualConstant, operation);
+                    var leftIsConstant = UsePatternMatchingForEqualityComparisonsCommon.IsConstantLiteral(operation.LeftOperand);
+                    var rightIsConstant = UsePatternMatchingForEqualityComparisonsCommon.IsConstantLiteral(operation.RightOperand);
+                    if (leftIsConstant ^ rightIsConstant)
+                    {
+                        if (_operationUtilities.IsInExpressionContext(operation))
+                            return;
+
+                        context.ReportDiagnostic(operation.OperatorKind is BinaryOperatorKind.Equals ? RuleEqualConstant : RuleNotEqualConstant, operation);
+                    }
                 }
             }
         }
     }
+
 }
diff --git a/tests/Meziantou.Analyzer.Test/Rules/UsePatternMatchingForEqualityComparisonsAnalyzerTests.cs b/tests/Meziantou.Analyzer.Test/Rules/UsePatternMatchingForEqualityComparisonsAnalyzerTests.cs
@@ -15,6 +15,19 @@ private static ProjectBuilder CreateProjectBuilder()
             .WithCodeFixProvider<UsePatternMatchingForEqualityComparisonsFixer>();
     }
 
+    [Fact]
+    public async Task DisabledInExpression()
+    {
+        await CreateProjectBuilder()
+              .WithSourceCode("""              
+                  using System;
+                  using System.Linq;
+                  using System.Linq.Expressions;
+                  _ = (Expression<Func<int, bool>>)(item => item == 0);
+                  """)
+              .ValidateAsync();
+    }
+
     [Fact]
     public async Task NullCheckForNullableOfT()
     {