[clang-tidy] new google-default-arguments check

Summary:
To check the google style guide rule here:
https://google.github.io/styleguide/cppguide.html#Default_Arguments

Patch by Clement Courbet!

Reviewers: hokein

Subscribers: cfe-commits

Differential Revision: http://reviews.llvm.org/D19534

llvm-svn: 268919

1 files changed, 36 insertions, 0 deletions

diff --git a/clang-tools-extra/clang-tidy/google/DefaultArgumentsCheck.cpp b/clang-tools-extra/clang-tidy/google/DefaultArgumentsCheck.cpp
new file mode 100644
index 00000000000..ccbd870a6ec
--- /dev/null
+++ b/clang-tools-extra/clang-tidy/google/DefaultArgumentsCheck.cpp
@@ -0,0 +1,36 @@
+//===--- DefaultArgumentsCheck.cpp - clang-tidy----------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include "DefaultArgumentsCheck.h"
+#include "clang/AST/ASTContext.h"
+#include "clang/ASTMatchers/ASTMatchFinder.h"
+
+using namespace clang::ast_matchers;
+
+namespace clang {
+namespace tidy {
+namespace google {
+
+void DefaultArgumentsCheck::registerMatchers(MatchFinder *Finder) {
+  Finder->addMatcher(
+      cxxMethodDecl(anyOf(isOverride(), isVirtual()),
+                    hasAnyParameter(parmVarDecl(hasInitializer(expr()))))
+          .bind("Decl"),
+      this);
+}
+
+void DefaultArgumentsCheck::check(const MatchFinder::MatchResult &Result) {
+  const auto *MatchedDecl = Result.Nodes.getNodeAs<CXXMethodDecl>("Decl");
+  diag(MatchedDecl->getLocation(),
+       "default arguments on virtual or override methods are prohibited");
+}
+
+} // namespace google
+} // namespace tidy
+} // namespace clang