[clang-tidy][NFC] Use C++17 nested namespaces in add_new_check.py and rename_check.py

[carlosgalvezp]

Update release notes

[Eugene.Zelenko]

But will be good idea if other eyes will look too.

[njames93]

LGTM, just a couple points

clang-tools-extra/clang-tidy/rename_check.py

311–314

I'd argue the change to update all checks should go in at the same time.

clang-tools-extra/docs/ReleaseNotes.rst

109–110 ↗

(On Diff #489271)

Such a trivial change like this probably doesn't need to go in the release notes, @Eugene.Zelenko thoughts?

[carlosgalvezp]

clang-tools-extra/clang-tidy/rename_check.py

311–314

Patch for that here, would you like me to merge them?

https://reviews.llvm.org/D141770

[Eugene.Zelenko]

clang-tools-extra/clang-tidy/rename_check.py

311

Clang-tidy or just all checks, since script is about Clang-tidy.

[Eugene.Zelenko]

clang-tools-extra/docs/ReleaseNotes.rst

109–110 ↗

(On Diff #489271)

Probably should not, since entire code base was moved to C++17.

[carlosgalvezp]

clang-tools-extra/clang-tidy/rename_check.py

311–314

Let's do everything in the same patch, I'll abandon this.

[carlosgalvezp]

Merged into https://reviews.llvm.org/D141770

clang-tools-extra/clang-tidy/add_new_check.py

 //
 //===----------------------------------------------------------------------===//
 
 #ifndef %(header_guard)s
 #define %(header_guard)s
 
 #include "../ClangTidyCheck.h"
 
-namespace clang {
-namespace tidy {
-namespace %(namespace)s {
+namespace clang::tidy::%(namespace)s {
 
 /// FIXME: Write a short description.
 ///
 /// For the user-facing documentation see:
 /// http://clang.llvm.org/extra/clang-tidy/checks/%(module)s/%(check_name)s.html
 class %(check_name_camel)s : public ClangTidyCheck {
 public:
   %(check_name_camel)s(StringRef Name, ClangTidyContext *Context)
       : ClangTidyCheck(Name, Context) {}
   void registerMatchers(ast_matchers::MatchFinder *Finder) override;
   void check(const ast_matchers::MatchFinder::MatchResult &Result) override;
 };
 
-} // namespace %(namespace)s
-} // namespace tidy
-} // namespace clang
+} // namespace clang::tidy::%(namespace)s
 
 #endif // %(header_guard)s
 """ % {'header_guard': header_guard,
        'check_name_camel': check_name_camel,
        'check_name': check_name,
        'module': module,
        'namespace': namespace})
 

 //===----------------------------------------------------------------------===//
 
 #include "%(check_name)s.h"
 #include "clang/AST/ASTContext.h"
 #include "clang/ASTMatchers/ASTMatchFinder.h"
 
 using namespace clang::ast_matchers;
 
-namespace clang {
-namespace tidy {
-namespace %(namespace)s {
+namespace clang::tidy::%(namespace)s {
 
 void %(check_name)s::registerMatchers(MatchFinder *Finder) {
   // FIXME: Add matchers.
   Finder->addMatcher(functionDecl().bind("x"), this);
 }
 
 void %(check_name)s::check(const MatchFinder::MatchResult &Result) {
   // FIXME: Add callback implementation.
   const auto *MatchedDecl = Result.Nodes.getNodeAs<FunctionDecl>("x");
   if (!MatchedDecl->getIdentifier() || MatchedDecl->getName().startswith("awesome_"))
     return;
   diag(MatchedDecl->getLocation(), "function %%0 is insufficiently awesome")
       << MatchedDecl;
   diag(MatchedDecl->getLocation(), "insert 'awesome'", DiagnosticIDs::Note)
       << FixItHint::CreateInsertion(MatchedDecl->getLocation(), "awesome_");
 }
 
-} // namespace %(namespace)s
-} // namespace tidy
-} // namespace clang
+} // namespace clang::tidy::%(namespace)s
 """ % {'check_name': check_name_camel,
        'module': module,
        'namespace': namespace})
 
 
 # Returns the source filename that implements the module.
 def get_module_filename(module_path, module):
   modulecpp = list(filter(

clang-tools-extra/clang-tidy/rename_check.py

if new_module == 'llvm':
       new_namespace = new_module + '_check'
     else:
       new_namespace = new_module
     check_implementation_files = glob.glob(
         os.path.join(old_module_path, new_check_name_camel + '*'))
     for filename in check_implementation_files:
       # Move check implementation to the directory of the new module.
       filename = fileRename(filename, old_module_path, new_module_path)
+      # TODO: remove below replacement when all clang-tidy checks have been
+      # updated with C++17 nested namespaces.
       replaceInFileRegex(filename, 'namespace ' + old_module + '[^ \n]*',
                          'namespace ' + new_namespace)
+      replaceInFileRegex(filename,
+                         'namespace clang::tidy::' + old_module + '[^ \n]*',
+                         'namespace clang::tidy::' + new_namespace)
 
   if (args.old_check_name == args.new_check_name):
     return
 
   # Add check to the new module.
   adapt_cmake(new_module_path, new_check_name_camel)
   adapt_module(new_module_path, new_module, args.new_check_name,
                new_check_name_camel)
 
   os.system(os.path.join(clang_tidy_path, 'add_new_check.py')
             + ' --update-docs')
   add_release_notes(clang_tidy_path, args.old_check_name, args.new_check_name)
 
 
 if __name__ == '__main__':
   main()