[change-namepsace] make it possible to whitelist symbols so they don't get updated.

Reviewers: hokein

Reviewed By: hokein

Subscribers: cfe-commits

Differential Revision: https://reviews.llvm.org/D30328

3 files changed, 39 insertions, 1 deletions

diff --git a/clang-tools-extra/change-namespace/ChangeNamespace.cpp b/clang-tools-extra/change-namespace/ChangeNamespace.cpp
index ebd6daeebc5..ad1c22afcdb 100644
--- a/clang-tools-extra/change-namespace/ChangeNamespace.cpp
+++ b/clang-tools-extra/change-namespace/ChangeNamespace.cpp
@@ -290,6 +290,7 @@ AST_MATCHER(EnumDecl, isScoped) {
 
 ChangeNamespaceTool::ChangeNamespaceTool(
     llvm::StringRef OldNs, llvm::StringRef NewNs, llvm::StringRef FilePattern,
+    llvm::ArrayRef<std::string> WhiteListedSymbolPatterns,
     std::map<std::string, tooling::Replacements> *FileToReplacements,
     llvm::StringRef FallbackStyle)
     : FallbackStyle(FallbackStyle), FileToReplacements(*FileToReplacements),
@@ -308,6 +309,9 @@ ChangeNamespaceTool::ChangeNamespaceTool(
   }
   DiffOldNamespace = joinNamespaces(OldNsSplitted);
   DiffNewNamespace = joinNamespaces(NewNsSplitted);
+
+  for (const auto &Pattern : WhiteListedSymbolPatterns)
+    WhiteListedSymbolRegexes.emplace_back(Pattern);
 }
 
 void ChangeNamespaceTool::registerMatchers(ast_matchers::MatchFinder *Finder) {
@@ -736,6 +740,9 @@ void ChangeNamespaceTool::replaceQualifiedSymbolInDeclContext(
           Result.SourceManager->getSpellingLoc(End)),
       *Result.SourceManager, Result.Context->getLangOpts());
   std::string FromDeclName = FromDecl->getQualifiedNameAsString();
+  for (llvm::Regex &RE : WhiteListedSymbolRegexes)
+    if (RE.match(FromDeclName))
+      return;
   std::string ReplaceName =
       getShortestQualifiedNameInNamespace(FromDeclName, NewNs);
   // Checks if there is any using namespace declarations that can shorten the
diff --git a/clang-tools-extra/change-namespace/ChangeNamespace.h b/clang-tools-extra/change-namespace/ChangeNamespace.h
index 5161591db37..cfe3cbc729d 100644
--- a/clang-tools-extra/change-namespace/ChangeNamespace.h
+++ b/clang-tools-extra/change-namespace/ChangeNamespace.h
@@ -50,6 +50,7 @@ public:
   // files matching `FilePattern`.
   ChangeNamespaceTool(
       llvm::StringRef OldNs, llvm::StringRef NewNs, llvm::StringRef FilePattern,
+      llvm::ArrayRef<std::string> WhiteListedSymbolPatterns,
       std::map<std::string, tooling::Replacements> *FileToReplacements,
       llvm::StringRef FallbackStyle = "LLVM");
 
@@ -164,6 +165,9 @@ private:
   // CallExpr and one as DeclRefExpr), we record all DeclRefExpr's that have
   // been processed so that we don't handle them twice.
   llvm::SmallPtrSet<const clang::DeclRefExpr*, 16> ProcessedFuncRefs;
+  // Patterns of symbol names whose references are not expected to be updated
+  // when changing namespaces around them.
+  std::vector<llvm::Regex> WhiteListedSymbolRegexes;
 };
 
 } // namespace change_namespace
diff --git a/clang-tools-extra/change-namespace/tool/ClangChangeNamespace.cpp b/clang-tools-extra/change-namespace/tool/ClangChangeNamespace.cpp
index b49a78d6e87..02a97839f15 100644
--- a/clang-tools-extra/change-namespace/tool/ClangChangeNamespace.cpp
+++ b/clang-tools-extra/change-namespace/tool/ClangChangeNamespace.cpp
@@ -73,6 +73,25 @@ cl::opt<std::string> Style("style",
                            cl::desc("The style name used for reformatting."),
                            cl::init("LLVM"), cl::cat(ChangeNamespaceCategory));
 
+cl::opt<std::string> WhiteListFile(
+    "whitelist_file",
+    cl::desc("A file containing regexes of symbol names that are not expected "
+             "to be updated when changing namespaces around them."),
+    cl::init(""), cl::cat(ChangeNamespaceCategory));
+
+llvm::ErrorOr<std::vector<std::string>> GetWhiteListedSymbolPatterns() {
+  llvm::SmallVector<StringRef, 8> Lines;
+  if (!WhiteListFile.empty()) {
+    llvm::ErrorOr<std::unique_ptr<llvm::MemoryBuffer>> File =
+        llvm::MemoryBuffer::getFile(WhiteListFile);
+    if (!File)
+      return File.getError();
+    llvm::StringRef Content = File.get()->getBuffer();
+    Content.split(Lines, '\n', /*MaxSplit=*/-1, /*KeepEmpty=*/false);
+  }
+  return std::vector<std::string>(Lines.begin(), Lines.end());
+}
+
 } // anonymous namespace
 
 int main(int argc, const char **argv) {
@@ -81,8 +100,16 @@ int main(int argc, const char **argv) {
                                              ChangeNamespaceCategory);
   const auto &Files = OptionsParser.getSourcePathList();
   tooling::RefactoringTool Tool(OptionsParser.getCompilations(), Files);
+  llvm::ErrorOr<std::vector<std::string>> WhiteListPatterns =
+      GetWhiteListedSymbolPatterns();
+  if (!WhiteListPatterns) {
+    llvm::errs() << "Failed to open whitelist file " << WhiteListFile << ". "
+                 << WhiteListPatterns.getError().message() << "\n";
+    return 1;
+  }
   change_namespace::ChangeNamespaceTool NamespaceTool(
-      OldNamespace, NewNamespace, FilePattern, &Tool.getReplacements(), Style);
+      OldNamespace, NewNamespace, FilePattern, *WhiteListPatterns,
+      &Tool.getReplacements(), Style);
   ast_matchers::MatchFinder Finder;
   NamespaceTool.registerMatchers(&Finder);
   std::unique_ptr<tooling::FrontendActionFactory> Factory =