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diff --git a/clang-tools-extra/clang-tidy/readability/ContainerSizeEmptyCheck.h b/clang-tools-extra/clang-tidy/readability/ContainerSizeEmptyCheck.h
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+++ b/clang-tools-extra/clang-tidy/readability/ContainerSizeEmptyCheck.h
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+//===--- ContainerSizeEmptyCheck.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_READABILITY_CONTAINERSIZEEMPTYCHECK_H
+#define LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_READABILITY_CONTAINERSIZEEMPTYCHECK_H
+
+#include "../ClangTidy.h"
+
+namespace clang {
+namespace tidy {
+namespace readability {
+
+/// \brief Checks whether a call to the \c size() method can be replaced with a
+/// call to \c empty().
+///
+/// The emptiness of a container should be checked using the \c empty() method
+/// instead of the \c size() method. It is not guaranteed that \c size() is a
+/// constant-time function, and it is generally more efficient and also shows
+/// clearer intent to use \c empty(). Furthermore some containers may implement
+/// the \c empty() method but not implement the \c size() method. Using \c
+/// empty() whenever possible makes it easier to switch to another container in
+/// the future.
+class ContainerSizeEmptyCheck : public ClangTidyCheck {
+public:
+  ContainerSizeEmptyCheck(StringRef Name, ClangTidyContext *Context);
+  void registerMatchers(ast_matchers::MatchFinder *Finder) override;
+  void check(const ast_matchers::MatchFinder::MatchResult &Result) override;
+};
+
+} // namespace readability
+} // namespace tidy
+} // namespace clang
+
+#endif // LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_READABILITY_CONTAINERSIZEEMPTYCHECK_H