[clang-tidy] Add non-constant references in function parameters check.

Summary: This is implemented originally by Alexander Kornienko.

Reviewers: alexfh

Subscribers: cfe-commits


Patch by Haojian Wu!

Differential Revision: http://reviews.llvm.org/D16717

llvm-svn: 259530
diff --git a/clang-tools-extra/clang-tidy/google/NonConstReferences.h b/clang-tools-extra/clang-tidy/google/NonConstReferences.h
new file mode 100644
index 0000000..3adb1f9
--- /dev/null
+++ b/clang-tools-extra/clang-tidy/google/NonConstReferences.h
@@ -0,0 +1,36 @@
+//===--- NonConstReferences.h - clang-tidy ----------------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_GOOGLE_NON_CONST_REFERENCES_H
+#define LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_GOOGLE_NON_CONST_REFERENCES_H
+
+#include "../ClangTidy.h"
+
+namespace clang {
+namespace tidy {
+namespace google {
+namespace runtime {
+
+/// \brief Checks the usage of non-constant references in function parameters.
+///
+/// https://google.github.io/styleguide/cppguide.html#Reference_Arguments
+class NonConstReferences : public ClangTidyCheck {
+public:
+  NonConstReferences(StringRef Name, ClangTidyContext *Context)
+      : ClangTidyCheck(Name, Context) {}
+  void registerMatchers(ast_matchers::MatchFinder *Finder) override;
+  void check(const ast_matchers::MatchFinder::MatchResult &Result) override;
+};
+
+} // namespace runtime
+} // namespace google
+} // namespace tidy
+} // namespace clang
+
+#endif // LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_GOOGLE_NON_CONST_REFERENCES_H