[clang-tidy][NFC] Refactor bugprone-argument-comment [1/3]

[zeyi2]

This is a necessary step to land #171757

Part of #170921

[llvmbot]

@llvm/pr-subscribers-clang-tools-extra

@llvm/pr-subscribers-clang-tidy

Author: mitchell (zeyi2)

Changes

This is a necessary step to land #171757

Part of #170921

---

Full diff: https://github.com/llvm/llvm-project/pull/172521.diff

1 Files Affected:

• (modified) clang-tools-extra/clang-tidy/bugprone/ArgumentCommentCheck.cpp (+31-18)

diff --git a/clang-tools-extra/clang-tidy/bugprone/ArgumentCommentCheck.cpp b/clang-tools-extra/clang-tidy/bugprone/ArgumentCommentCheck.cpp
index ed30d01e645d1..0cb4f2f234dc0 100644
--- a/clang-tools-extra/clang-tidy/bugprone/ArgumentCommentCheck.cpp
+++ b/clang-tools-extra/clang-tidy/bugprone/ArgumentCommentCheck.cpp
@@ -142,31 +142,44 @@ getCommentsBeforeLoc(ASTContext *Ctx, SourceLocation Loc) {
   return Comments;
 }
 
-static bool isLikelyTypo(llvm::ArrayRef<ParmVarDecl *> Params,
-                         StringRef ArgName, unsigned ArgIndex) {
-  const std::string ArgNameLowerStr = ArgName.lower();
-  const StringRef ArgNameLower = ArgNameLowerStr;
+static llvm::SmallString<64> getLowercasedString(StringRef Name) {
+  llvm::SmallString<64> Result;
+  Result.reserve(Name.size());
+  for (char C : Name)
+    Result.push_back(llvm::toLower(C));
+  return Result;
+}
+
+template <typename NamedDeclRange>
+static bool isLikelyTypo(const NamedDeclRange &Candidates, StringRef ArgName,
+                         StringRef TargetName) {
+  const llvm::SmallString<64> ArgNameLower = getLowercasedString(ArgName);
+  const StringRef ArgNameLowerRef = StringRef(ArgNameLower);
   // The threshold is arbitrary.
   const unsigned UpperBound = ((ArgName.size() + 2) / 3) + 1;
-  const unsigned ThisED = ArgNameLower.edit_distance(
-      Params[ArgIndex]->getIdentifier()->getName().lower(),
-      /*AllowReplacements=*/true, UpperBound);
+  const llvm::SmallString<64> TargetNameLower = getLowercasedString(TargetName);
+  const unsigned ThisED =
+      ArgNameLowerRef.edit_distance(StringRef(TargetNameLower),
+                                    /*AllowReplacements=*/true, UpperBound);
   if (ThisED >= UpperBound)
     return false;
 
-  for (unsigned I = 0, E = Params.size(); I != E; ++I) {
-    if (I == ArgIndex)
+  for (const auto &Candidate : Candidates) {
+    const IdentifierInfo *II = Candidate->getIdentifier();
+    if (II->getName() == TargetName)
       continue;
-    const IdentifierInfo *II = Params[I]->getIdentifier();
+
     if (!II)
       continue;
 
     const unsigned Threshold = 2;
-    // Other parameters must be an edit distance at least Threshold more away
-    // from this parameter. This gives us greater confidence that this is a
-    // typo of this parameter and not one with a similar name.
-    const unsigned OtherED = ArgNameLower.edit_distance(
-        II->getName().lower(),
+    // Other candidates must be an edit distance at least Threshold more away
+    // from this candidate. This gives us greater confidence that this is a
+    // typo of this candidate and not one with a similar name.
+    const llvm::SmallString<64> CandidateLower =
+        getLowercasedString(II->getName());
+    const unsigned OtherED = ArgNameLowerRef.edit_distance(
+        StringRef(CandidateLower),
         /*AllowReplacements=*/true, ThisED + Threshold);
     if (OtherED < ThisED + Threshold)
       return false;
@@ -319,7 +332,7 @@ void ArgumentCommentCheck::checkCallArgs(ASTContext *Ctx,
               diag(Comment.first, "argument name '%0' in comment does not "
                                   "match parameter name %1")
               << Matches[2] << II;
-          if (isLikelyTypo(Callee->parameters(), Matches[2], I)) {
+          if (isLikelyTypo(Callee->parameters(), Matches[2], II->getName())) {
             Diag << FixItHint::CreateReplacement(
                 Comment.first, (Matches[1] + II->getName() + Matches[3]).str());
           }
@@ -335,8 +348,8 @@ void ArgumentCommentCheck::checkCallArgs(ASTContext *Ctx,
 
     // If the argument comments are missing for literals add them.
     if (Comments.empty() && shouldAddComment(Args[I])) {
-      const std::string ArgComment =
-          (llvm::Twine("/*") + II->getName() + "=*/").str();
+      llvm::SmallString<32> ArgComment;
+      (llvm::Twine("/*") + II->getName() + "=*/").toStringRef(ArgComment);
       const DiagnosticBuilder Diag =
           diag(Args[I]->getBeginLoc(),
                "argument comment missing for literal argument %0")

[github-actions]

✅ With the latest revision this PR passed the C/C++ code linter.

[zeyi2]

This was added mainly to avoid the use of std::string