[PATCH] D42464: add prefix with '_' support for property name. Corresponding apple dev doc: https://developer.apple.com/library/content/qa/qa1908/_index.html

[Haojian Wu via Phabricator via cfe-commits]

hokein added inline comments.


================
Comment at: clang-tidy/objc/PropertyDeclarationCheck.cpp:115
+
+bool prefixedPropertyNameMatches(const llvm::StringRef &PropertyName,
+                                 const std::vector<std::string> &Acronyms) {
----------------
Wizard wrote:
> hokein wrote:
> > no need to pass const reference of `llvm::StringRef`. `StringRef` is cheap.
> The original property name I directly get from ast is a const. If I remove the const here, I will have to make a copy of the property name before calling this.
> I prefer keep this const to save that copy :-)
Why? `MatchedDecl->getName()` returns `llvm::StringRef`. As the name indicates, StringRef is a const reference of String, using StringRef is sufficient.

The same to ArrayRef. So the function is like `bool prefixedPropertyNameMatches(llvm::StringRef PropertyName, llvm::ArrayRef<std::string> Acronyms)`.




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Comment at: clang-tidy/objc/PropertyDeclarationCheck.cpp:151
+      hasCategoryPropertyPrefix(MatchedDecl->getName())) {
+    const auto *CategoryDecl = (const ObjCCategoryDecl *)(DeclContext);
+    if (!prefixedPropertyNameMatches(MatchedDecl->getName(), SpecialAcronyms) ||
----------------
Wizard wrote:
> hokein wrote:
> > Consider using `const auto* CategoryDecl = dyn_cast<ObjCCategoryDecl*>(DeclContext)`, we can get rid of this cast, and `NodeKind` variable.
> Tried that before but I encountered 2 issues:
> 1. 'clang::DeclContext' is not polymorphic
> 2. cannot use dynamic_cast with -fno-rtti
> which are preventing me from using dynamic_cast
Sorry, I mean `llvm::dyn_cast` here, it should work.


================
Comment at: clang-tidy/objc/PropertyDeclarationCheck.cpp:67
+  if (Style == CategoryProperty) {
+    for (size_t i = 0; i < Name.size(); ++i) {
+      if (Name[i] == '_') {
----------------
I think we save this code by using `find_first_of` and `llvm::StringRef::tolower()` function.


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Comment at: clang-tidy/objc/PropertyDeclarationCheck.cpp:95
+// in matchers or not.
+std::string validPropertyNameRegex(const std::vector<std::string> &Acronyms,
+                                   bool UsedInMatcher) {
----------------
The same, ArrayRef.


================
Comment at: clang-tidy/objc/PropertyDeclarationCheck.cpp:121
+
+bool hasCategoryPropertyPrefix(const llvm::StringRef &PropertyName) {
+  auto RegexExp = llvm::Regex("^[a-z]+_[a-zA-Z0-9][a-zA-Z0-9_]+$");
----------------
The same: `llvm::StringRef`


================
Comment at: clang-tidy/objc/PropertyDeclarationCheck.cpp:163
+            MatchedDecl->getName(),
+            llvm::ArrayRef<std::string>(SpecialAcronyms)) ||
+        CategoryDecl->IsClassExtension()) {
----------------
Do we need it? I think you can pass `SpecialAcronyms` directly.


Repository:
  rCTE Clang Tools Extra

https://reviews.llvm.org/D42464