From 28aaa560de7c56b6c7c1c2b9b9623914760548f1 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?G=C3=A9rald=20Barr=C3=A9?= <git@meziantou.net>
Date: Mon, 18 May 2026 16:06:17 -0400
Subject: [PATCH] Fix MA0194 merge parenthesization

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
---
 .../Rules/MergeIsPatternChecksFixer.cs            |  9 +++++++--
 .../Rules/MergeIsPatternChecksAnalyzerTests.cs    | 15 +++++++++++++++
 2 files changed, 22 insertions(+), 2 deletions(-)

diff --git a/src/Meziantou.Analyzer.CodeFixers/Rules/MergeIsPatternChecksFixer.cs b/src/Meziantou.Analyzer.CodeFixers/Rules/MergeIsPatternChecksFixer.cs
index 0b34641e9..f4c1343eb 100644
--- a/src/Meziantou.Analyzer.CodeFixers/Rules/MergeIsPatternChecksFixer.cs
+++ b/src/Meziantou.Analyzer.CodeFixers/Rules/MergeIsPatternChecksFixer.cs
@@ -207,8 +207,7 @@ private static PatternSyntax ParenthesizePatternIfNeeded(PatternSyntax pattern,
             return pattern;
 
         if (pattern is BinaryPatternSyntax binaryPattern &&
-            parentPatternKind is SyntaxKind.AndPattern &&
-            binaryPattern.Kind() is SyntaxKind.OrPattern)
+            (parentPatternKind, binaryPattern.Kind()) is (SyntaxKind.AndPattern, SyntaxKind.OrPattern) or (SyntaxKind.OrPattern, SyntaxKind.AndPattern))
         {
             return ParenthesizedPattern(pattern);
         }
@@ -266,6 +265,12 @@ private static IOperation UnwrapOperation(IOperation operation)
 
     private static bool TryCreatePatternSyntax(IPatternOperation patternOperation, out PatternSyntax patternSyntax)
     {
+        if (patternOperation.Syntax is PatternSyntax patternFromSyntax)
+        {
+            patternSyntax = patternFromSyntax;
+            return true;
+        }
+
         switch (patternOperation)
         {
             case IConstantPatternOperation constantPatternOperation:
diff --git a/tests/Meziantou.Analyzer.Test/Rules/MergeIsPatternChecksAnalyzerTests.cs b/tests/Meziantou.Analyzer.Test/Rules/MergeIsPatternChecksAnalyzerTests.cs
index b1b4253b8..759545579 100644
--- a/tests/Meziantou.Analyzer.Test/Rules/MergeIsPatternChecksAnalyzerTests.cs
+++ b/tests/Meziantou.Analyzer.Test/Rules/MergeIsPatternChecksAnalyzerTests.cs
@@ -89,6 +89,21 @@ enum MyEnum { Value1, Value2 }
               .ValidateAsync();
     }
 
+    [Fact]
+    public async Task LogicalOr_ParenthesizeAndPattern()
+    {
+        await CreateProjectBuilder()
+              .WithSourceCode("""
+                  byte marker = 0;
+                  _ = [|marker is 0x01 || marker is >= 0xD0 and <= 0xD7|];
+                  """)
+              .ShouldFixCodeWith("""
+                  byte marker = 0;
+                  _ = marker is 0x01 or (>= 0xD0 and <= 0xD7);
+                  """)
+              .ValidateAsync();
+    }
+
     [Fact]
     public async Task DifferentExpressions_DoNotReport()
     {