From 60f965b1f62c0c77bcdb2997ea9bb6603aa0d002 Mon Sep 17 00:00:00 2001
From: hehuan <111408804+xxxxbc@users.noreply.github.com>
Date: Sat, 1 Aug 2026 19:09:50 +0800
Subject: [PATCH] [clang-tidy] Fix trailing semicolon and lost comment in
 readability-use-std-min-max (#208782)

Fix two bugs in readability-use-std-min-max when the if body has no
braces.

For brace-less if bodies, If->getEndLoc() points to the expression end
rather than the trailing semicolon, truncating replacements and losing
comments. We find the semicolon via findNextToken and extend the range
consistent with compound statement logic.

Before:
  if (n < -1) n = -1 ;          ->  n = std::max(n, -1); ;
  if (n > 1) n = 1/*comment*/;  ->  n = std::min(n, 1);;

After:
  if (n < -1) n = -1 ;          ->  n = std::max(n, -1);
  if (n > 1) n = 1/*comment*/;  ->  n = std::min(n, 1); /*comment*/

Fixes #208708.

AI Usage: This patch is AI-assisted, reviewed and verified by me.
---
 .../clang-tidy/readability/UseStdMinMaxCheck.cpp     |  8 +++++++-
 clang-tools-extra/docs/ReleaseNotes.rst              |  4 ++++
 .../checkers/readability/use-std-min-max.cpp         | 12 ++++++++++++
 3 files changed, 23 insertions(+), 1 deletion(-)

diff --git a/clang-tools-extra/clang-tidy/readability/UseStdMinMaxCheck.cpp b/clang-tools-extra/clang-tidy/readability/UseStdMinMaxCheck.cpp
index ed1af05d232c..38e6dfb5328f 100644
--- a/clang-tools-extra/clang-tidy/readability/UseStdMinMaxCheck.cpp
+++ b/clang-tools-extra/clang-tidy/readability/UseStdMinMaxCheck.cpp
@@ -167,7 +167,7 @@ void UseStdMinMaxCheck::check(const MatchFinder::MatchResult &Result) {
   const auto *BinaryOp = Result.Nodes.getNodeAs<BinaryOperator>("binaryOp");
   const BinaryOperatorKind BinaryOpcode = BinaryOp->getOpcode();
   const SourceLocation IfLocation = If->getIfLoc();
-  const SourceLocation ThenLocation = If->getEndLoc();
+  SourceLocation ThenLocation = If->getEndLoc();
 
   auto ReplaceAndDiagnose = [&](const StringRef FunctionName) {
     const SourceManager &Source = *Result.SourceManager;
@@ -218,6 +218,12 @@ void UseStdMinMaxCheck::check(const MatchFinder::MatchResult &Result) {
       if (Semi != StringRef::npos && PostInner.take_front(Semi).trim().empty())
         PostInner = PostInner.drop_front(Semi + 1);
       AppendNormalized(PostInner);
+    } else if (const auto SemiTok =
+                   Lexer::findNextToken(ThenLocation, Source, LO);
+               SemiTok && SemiTok->is(tok::semi)) {
+      AppendNormalized(
+          GetSourceText(ThenLocation, SemiTok->getLocation()).rtrim());
+      ThenLocation = SemiTok->getLocation();
     }
 
     diag(IfLocation, "use `%0` instead of `%1`")
diff --git a/clang-tools-extra/docs/ReleaseNotes.rst b/clang-tools-extra/docs/ReleaseNotes.rst
index 9a5a23f3d854..66ce08534cae 100644
--- a/clang-tools-extra/docs/ReleaseNotes.rst
+++ b/clang-tools-extra/docs/ReleaseNotes.rst
@@ -121,6 +121,10 @@ Changes in existing checks
   exclusively for overload resolution. Added the :option:`IgnoredTypes`
   option to allow customizing the set of ignored types.
 
+- Improved :doc:`readability-use-std-min-max
+  <clang-tidy/checks/readability/use-std-min-max>` check by fixing spurious
+  trailing semicolons and lost comments when the ``if`` body has no braces.
+
 Removed checks
 ^^^^^^^^^^^^^^
 
diff --git a/clang-tools-extra/test/clang-tidy/checkers/readability/use-std-min-max.cpp b/clang-tools-extra/test/clang-tidy/checkers/readability/use-std-min-max.cpp
index 35570189e112..ebc3783e8465 100644
--- a/clang-tools-extra/test/clang-tidy/checkers/readability/use-std-min-max.cpp
+++ b/clang-tools-extra/test/clang-tidy/checkers/readability/use-std-min-max.cpp
@@ -253,6 +253,18 @@ void testVectorSizeType() {
     value = v.size();
 }
 
+namespace gh208708 {
+void f(int &n) {
+  // CHECK-MESSAGES: :[[@LINE+2]]:3: warning: use `std::max` instead of `<`
+  // CHECK-FIXES: n = std::max(n, -1);
+  if (n < -1) n = -1 ;
+
+  // CHECK-MESSAGES: :[[@LINE+2]]:3: warning: use `std::min` instead of `>`
+  // CHECK-FIXES: n = std::min(n, 1); /*use clamp when c++17 or later is enabled*/
+  if (n > 1) n = 1/*use clamp when c++17 or later is enabled*/;
+}
+} // namespace gh208708
+
 namespace gh121676 {
 
 void useLeft() {