Merge pull request #133 from bkoelman/fix-with-expr

Fixed AV1522: Skip assignments in 'with' expressions

Author: bkoelman

src/CSharpGuidelinesAnalyzer/CSharpGuidelinesAnalyzer.Test/Specs/Maintainability/AssignEachVariableInASeparateStatementSpecs.cs

@@ -1408,6 +1408,30 @@ void M(object o)
         await VerifyGuidelineDiagnosticAsync(source);
     }
 
+    [Fact]
+    internal async Task When_two_variables_are_declared_and_assigned_in_with_expression_it_must_be_skipped()
+    {
+        // Arrange
+        ParsedSourceCode source = new MemberSourceCodeBuilder()
+            .InDefaultClass(@"
+                void M(object o)
+                {
+                    X x1 = new X();
+                    X x2 = x1 with { P = 1 };
+                }
+
+                private struct X
+                {
+                    public int P { get; set; }
+                }
+            ")
+            .Build();
+
+        // Act and assert
+        await VerifyGuidelineDiagnosticAsync(source);
+    }
+
+
     protected override DiagnosticAnalyzer CreateAnalyzer()
     {
         return new AssignEachVariableInASeparateStatementAnalyzer();

src/CSharpGuidelinesAnalyzer/CSharpGuidelinesAnalyzer/Rules/Maintainability/AssignEachVariableInASeparateStatementAnalyzer.cs

@@ -152,6 +152,16 @@ public StatementWalker(ForLoopSection section)
                 this.section = section;
             }
 
+            public override void DefaultVisit([NotNull] IOperation operation)
+            {
+                // Check should be replaced with empty override of VisitWith(IWithOperation operation),
+                // after upgrade to recent version of Microsoft.CodeAnalysis.
+                if (operation.GetType().Name != "WithOperation")
+                {
+                    base.DefaultVisit(operation);
+                }
+            }
+
             public override void VisitVariableDeclarator([NotNull] IVariableDeclaratorOperation operation)
             {
                 IVariableInitializerOperation initializer = operation.GetVariableInitializer();