Recommit "[ClangTidy] Add UsingInserter and NamespaceAliaser"

Summary: This adds helper classes to add using declaractions and namespace aliases to function bodies. These help making function calls to deeply nested functions concise (e.g. when calling helpers in a refactoring)

Patch by Julian Bangert!

Reviewers: alexfh, hokein

Subscribers: beanz, mgorny, cfe-commits

Differential Revision: https://reviews.llvm.org/D24997

llvm-svn: 284368

1 files changed, 28 insertions, 0 deletions

diff --git a/clang-tools-extra/clang-tidy/utils/ASTUtils.cpp b/clang-tools-extra/clang-tidy/utils/ASTUtils.cpp
new file mode 100644
index 00000000000..cedac4f56f2
--- /dev/null
+++ b/clang-tools-extra/clang-tidy/utils/ASTUtils.cpp
@@ -0,0 +1,28 @@
+//===---------- ASTUtils.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 "ASTUtils.h"
+
+#include "clang/ASTMatchers/ASTMatchFinder.h"
+#include "clang/ASTMatchers/ASTMatchers.h"
+
+namespace clang {
+namespace tidy {
+namespace utils {
+using namespace ast_matchers;
+
+const FunctionDecl *getSurroundingFunction(ASTContext &Context,
+                                           const Stmt &Statement) {
+  return selectFirst<const FunctionDecl>(
+      "function", match(stmt(hasAncestor(functionDecl().bind("function"))),
+                        Statement, Context));
+}
+} // namespace utils
+} // namespace tidy
+} // namespace clang