llvm-project/clang-tools-extra/clang-tidy/readability/ContainerSizeEmptyCheck.h

//===--- 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 {

/// Checks whether a call to the `size()` method can be replaced with a call to
/// `empty()`.
///
/// The emptiness of a container should be checked using the `empty()` method
/// instead of the `size()` method. It is not guaranteed that `size()` is a
/// constant-time function, and it is generally more efficient and also shows
/// clearer intent to use `empty()`. Furthermore some containers may implement
/// the `empty()` method but not implement the `size()` method. Using `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