From 412d5272afbe067e499be2023887152a9d1dea4c Mon Sep 17 00:00:00 2001
From: James Hargreaves <jamesHargreaves12@gmail.com>
Date: Tue, 27 Jun 2023 11:14:46 +0100
Subject: [PATCH] Fix RCS1146 (#1098)

Co-authored-by: Josef Pihrt <josef@pihrt.net>
---
 ChangeLog.md                                  |  1 +
 .../Analysis/UseConditionalAccessAnalyzer.cs  | 12 +++++++++++
 .../RCS1146UseConditionalAccessTests.cs       | 20 +++++++++++++++++++
 3 files changed, 33 insertions(+)

diff --git a/ChangeLog.md b/ChangeLog.md
index 56ba8c41c6..670d905a29 100644
--- a/ChangeLog.md
+++ b/ChangeLog.md
@@ -17,6 +17,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - Fix [RCS1197](https://github.com/JosefPihrt/Roslynator/blob/main/docs/analyzers/RCS1197.md) ([#1093](https://github.com/JosefPihrt/Roslynator/pull/1093)).
 - Fix [RCS1056](https://github.com/JosefPihrt/Roslynator/blob/main/docs/analyzers/RCS1056.md) ([#1096](https://github.com/JosefPihrt/Roslynator/pull/1096)).
 - Fix [RCS1216](https://github.com/JosefPihrt/Roslynator/blob/main/docs/analyzers/RCS1216.md) ([#1094](https://github.com/JosefPihrt/Roslynator/pull/1094)).
+- Fix [RCS1146](https://github.com/JosefPihrt/Roslynator/blob/main/docs/analyzers/RCS1146.md) ([#1098](https://github.com/JosefPihrt/Roslynator/pull/1098)).
 
 ## [4.3.0] - 2023-04-24
 
diff --git a/src/Analyzers/CSharp/Analysis/UseConditionalAccessAnalyzer.cs b/src/Analyzers/CSharp/Analysis/UseConditionalAccessAnalyzer.cs
index 2959fdd407..5bd49667fe 100644
--- a/src/Analyzers/CSharp/Analysis/UseConditionalAccessAnalyzer.cs
+++ b/src/Analyzers/CSharp/Analysis/UseConditionalAccessAnalyzer.cs
@@ -274,6 +274,18 @@ private static bool ValidateRightExpression(
                 case SyntaxKind.GreaterThanOrEqualExpression:
                 case SyntaxKind.EqualsExpression:
                     {
+                        var leftTypeSymbol = semanticModel.GetTypeSymbol(((BinaryExpressionSyntax)expression).Left);
+
+                        if (leftTypeSymbol.IsErrorType())
+                            return false;
+
+                        if (leftTypeSymbol.IsValueType && !CSharpFacts.IsPredefinedType(leftTypeSymbol.SpecialType))
+                        { 
+                            // If the LHS is a ValueTypes then making the expression conditional would change the type of the expression
+                            // and hence we would call a different overload (a valid overload may not exists)
+                            return false;
+                        }
+                        
                         expression = ((BinaryExpressionSyntax)expression)
                             .Right?
                             .WalkDownParentheses();
diff --git a/src/Tests/Analyzers.Tests/RCS1146UseConditionalAccessTests.cs b/src/Tests/Analyzers.Tests/RCS1146UseConditionalAccessTests.cs
index e523fc427e..f3c4c0b768 100644
--- a/src/Tests/Analyzers.Tests/RCS1146UseConditionalAccessTests.cs
+++ b/src/Tests/Analyzers.Tests/RCS1146UseConditionalAccessTests.cs
@@ -601,6 +601,26 @@ void M()
 ");
     }
 
+    [Fact, Trait(Traits.Analyzer, DiagnosticIdentifiers.UseConditionalAccess)]
+    public async Task TestNoDiagnostic_LogicalAnd_ValueTypeFieldAccess()
+    {
+        await VerifyNoDiagnosticAsync(@"
+struct Foo 
+{
+    public static bool operator ==(Foo left, string right) => left.Equals(right);
+    public static bool operator !=(Foo left, string right) => !(left == right);
+}
+class C
+{
+    public Foo F { get; } 
+    void M(C c)
+    {
+        if (c != null && c.F == ""someStr"") { }
+    }
+}
+");
+    }
+
     [Fact, Trait(Traits.Analyzer, DiagnosticIdentifiers.UseConditionalAccess)]
     public async Task TestNoDiagnostic_LogicalAnd_NullableType()
     {