[clang-tools-extra] b6d7d69 - [clang-tidy] Correct fix-it range for function pointer-like typedef in `modernize-use-using` (#173751)

[via cfe-commits]

Author: flovent
Date: 2025-12-29T19:52:22+08:00
New Revision: b6d7d69a408fa6737ceb5a8a9826f915eb1425e5

URL: https://github.com/llvm/llvm-project/commit/b6d7d69a408fa6737ceb5a8a9826f915eb1425e5
DIFF: https://github.com/llvm/llvm-project/commit/b6d7d69a408fa6737ceb5a8a9826f915eb1425e5.diff

LOG: [clang-tidy] Correct fix-it range for function pointer-like typedef in `modernize-use-using` (#173751)

Extends the function case to all function pointer-like cases, because
their source range contains name.
see more in https://github.com/llvm/llvm-project/pull/65558


Closes [#173732](https://github.com/llvm/llvm-project/issues/173732)

Added: 
    

Modified: 
    clang-tools-extra/clang-tidy/modernize/UseUsingCheck.cpp
    clang-tools-extra/docs/ReleaseNotes.rst
    clang-tools-extra/test/clang-tidy/checkers/modernize/use-using.cpp

Removed: 
    


################################################################################
diff  --git a/clang-tools-extra/clang-tidy/modernize/UseUsingCheck.cpp b/clang-tools-extra/clang-tidy/modernize/UseUsingCheck.cpp
index 4831963326c8d..085dbde60db61 100644
--- a/clang-tools-extra/clang-tidy/modernize/UseUsingCheck.cpp
+++ b/clang-tools-extra/clang-tidy/modernize/UseUsingCheck.cpp
@@ -130,13 +130,16 @@ void UseUsingCheck::check(const MatchFinder::MatchResult &Result) {
 
   const TypeLoc TL = MatchedDecl->getTypeSourceInfo()->getTypeLoc();
 
-  auto [Type, QualifierStr] = [MatchedDecl, this, &TL, &SM,
+  bool FunctionPointerCase = false;
+  auto [Type, QualifierStr] = [MatchedDecl, this, &TL, &FunctionPointerCase,
+                               &SM,
                                &LO]() -> std::pair<std::string, std::string> {
     SourceRange TypeRange = TL.getSourceRange();
 
     // Function pointer case, get the left and right side of the identifier
     // without the identifier.
     if (TypeRange.fullyContains(MatchedDecl->getLocation())) {
+      FunctionPointerCase = true;
       const auto RangeLeftOfIdentifier = CharSourceRange::getCharRange(
           TypeRange.getBegin(), MatchedDecl->getLocation());
       const auto RangeRightOfIdentifier = CharSourceRange::getCharRange(
@@ -205,8 +208,7 @@ void UseUsingCheck::check(const MatchFinder::MatchResult &Result) {
   }
 
   if (!ReplaceRange.getEnd().isMacroID()) {
-    const SourceLocation::IntTy Offset =
-        MatchedDecl->getFunctionType() ? 0 : Name.size();
+    const SourceLocation::IntTy Offset = FunctionPointerCase ? 0 : Name.size();
     LastReplacementEnd = ReplaceRange.getEnd().getLocWithOffset(Offset);
   }
 

diff  --git a/clang-tools-extra/docs/ReleaseNotes.rst b/clang-tools-extra/docs/ReleaseNotes.rst
index 86bfd1d489898..ce16f94816aa3 100644
--- a/clang-tools-extra/docs/ReleaseNotes.rst
+++ b/clang-tools-extra/docs/ReleaseNotes.rst
@@ -583,6 +583,10 @@ Changes in existing checks
   constructor call, and fixed a crash when handling format strings
   containing non-ASCII characters.
 
+- Improved :doc:`modernize-use-using
+  <clang-tidy/checks/modernize/use-using>` check to correctly provide fix-its
+  for typedefs of pointers or references to array types.
+
 - Improved :doc:`performance-unnecessary-copy-initialization
   <clang-tidy/checks/performance/unnecessary-copy-initialization>` by printing
   the type of the diagnosed variable.

diff  --git a/clang-tools-extra/test/clang-tidy/checkers/modernize/use-using.cpp b/clang-tools-extra/test/clang-tidy/checkers/modernize/use-using.cpp
index 5b8eca2825645..a1f32b06df091 100644
--- a/clang-tools-extra/test/clang-tidy/checkers/modernize/use-using.cpp
+++ b/clang-tools-extra/test/clang-tidy/checkers/modernize/use-using.cpp
@@ -437,3 +437,27 @@ namespace GH97009 {
 // CHECK-MESSAGES: :[[@LINE-1]]:3: warning: use 'using' instead of 'typedef' [modernize-use-using]
 // CHECK-FIXES: using Function = bool (*)(PointType, PointType);
 }
+
+namespace GH173732 {
+  // reference to array
+  typedef char (&refarray)[2];
+  // CHECK-MESSAGES: :[[@LINE-1]]:3: warning: use 'using' instead of 'typedef' [modernize-use-using]
+  // CHECK-FIXES: using refarray = char (&)[2];
+  typedef char &ref;
+  // CHECK-MESSAGES: :[[@LINE-1]]:3: warning: use 'using' instead of 'typedef' [modernize-use-using]
+  // CHECK-FIXES: using ref = char &;
+
+
+  // pointer to array
+  typedef char (*ptrarray)[2];
+  // CHECK-MESSAGES: :[[@LINE-1]]:3: warning: use 'using' instead of 'typedef' [modernize-use-using]
+  // CHECK-FIXES: using ptrarray = char (*)[2];
+  typedef char *ptr;
+  // CHECK-MESSAGES: :[[@LINE-1]]:3: warning: use 'using' instead of 'typedef' [modernize-use-using]
+  // CHECK-FIXES: using ptr = char *;
+
+  // multiple in one typedef
+  typedef char (&refArray)[2], (*ptrArray)[2];
+  // CHECK-MESSAGES: :[[@LINE-1]]:3: warning: use 'using' instead of 'typedef' [modernize-use-using]
+  // CHECK-MESSAGES: :[[@LINE-2]]:29: warning: use 'using' instead of 'typedef' [modernize-use-using]
+}