[clang-tools-extra] [clang-tid]fix modernize-use-auto incorrect fix hints for pointer (PR #77943)

[Congcong Cai via cfe-commits]

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@@ -405,12 +421,20 @@ void UseAutoCheck::replaceExpr(
 
   auto Diag = diag(Range.getBegin(), Message);
 
+  bool ShouldReplenishVariableName = isMutliLevelPointerToTypeLocClasses(
+      FirstDecl->getTypeSourceInfo()->getTypeLoc(),
+      {TypeLoc::FunctionProto, TypeLoc::ConstantArray});
+
   // Space after 'auto' to handle cases where the '*' in the pointer type is
   // next to the identifier. This avoids changing 'int *p' into 'autop'.
-  // FIXME: This doesn't work for function pointers because the variable name
-  // is inside the type.
-  Diag << FixItHint::CreateReplacement(Range, RemoveStars ? "auto " : "auto")
-       << StarRemovals;
+  llvm::StringRef Auto = ShouldReplenishVariableName
+                             ? (RemoveStars ? "auto " : "auto *")
+                             : (RemoveStars ? "auto " : "auto");
+  std::string ReplenishedVariableName =
+      ShouldReplenishVariableName ? FirstDecl->getQualifiedNameAsString() : "";
+  std::string Replacement =
+      (Auto + llvm::StringRef{ReplenishedVariableName}).str();
+  Diag << FixItHint::CreateReplacement(Range, Replacement) << StarRemovals;
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HerrCai0907 wrote:

It is very hard to split the variable name according to `TypeLoc` and `VarDecl`.

https://github.com/llvm/llvm-project/pull/77943