[clang-tools-extra] Add support for renaming objc methods, even those with multiple selector pieces (PR #76466)

[kadir çetinkaya via cfe-commits]

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@@ -543,6 +550,45 @@ std::optional<InvalidName> checkName(const NamedDecl &RenameDecl,
   return Result;
 }
 
+clangd::Range tokenRangeForLoc(ParsedAST &AST, SourceLocation TokLoc,
+                               const SourceManager &SM,
+                               const LangOptions &LangOpts) {
+  const auto *Token = AST.getTokens().spelledTokenAt(TokLoc);
+  assert(Token && "got inclusion at wrong offset");
+  clangd::Range Result;
+  Result.start = sourceLocToPosition(SM, Token->location());
+  Result.end = sourceLocToPosition(SM, Token->endLocation());
+  return Result;
+}
+
+// AST-based ObjC method rename, it renames all occurrences in the main file
+// even for selectors which may have multiple tokens.
+llvm::Expected<tooling::Replacements>
+renameObjCMethodWithinFile(ParsedAST &AST, const ObjCMethodDecl *MD,
+                           llvm::StringRef NewName,
+                           std::vector<SourceLocation> Locs) {
+  const SourceManager &SM = AST.getSourceManager();
+  auto Code = SM.getBufferData(SM.getMainFileID());
+  auto RenameIdentifier = MD->getSelector().getNameForSlot(0).str();
+  llvm::SmallVector<llvm::StringRef, 8> NewNames;
+  NewName.split(NewNames, ":");
+  if (NewNames.empty())
+    NewNames.push_back(NewName);
+
+  std::vector<Range> Ranges;
+  const auto &LangOpts = MD->getASTContext().getLangOpts();
+  for (const auto &Loc : Locs)
+    Ranges.push_back(tokenRangeForLoc(AST, Loc, SM, LangOpts));
+  auto FilePath = AST.tuPath();
+  auto RenameRanges = collectRenameIdentifierRanges(
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kadircet wrote:

well you know how I hate complexity :)) so I am definitely in favor of leaving it as-is.

https://github.com/llvm/llvm-project/pull/76466