# https://clang.llvm.org/extra/clang-tidy/checks/list.html
option(CMake_RUN_CLANG_TIDY "Run clang-tidy with the compiler." OFF)

if(CMake_RUN_CLANG_TIDY)
  if(CMake_SOURCE_DIR STREQUAL CMake_BINARY_DIR)
    message(FATAL_ERROR "CMake_RUN_CLANG_TIDY requires an out-of-source build!")
  endif()
  find_program(CLANG_TIDY_COMMAND NAMES clang-tidy)
  if(NOT CLANG_TIDY_COMMAND)
    message(FATAL_ERROR "CMake_RUN_CLANG_TIDY is ON but clang-tidy is not found!")
  endif()
  set(CMAKE_CXX_CLANG_TIDY "${CLANG_TIDY_COMMAND}")

  # Create a preprocessor definition that depends on .clang-tidy content so
  # the compile command will change when .clang-tidy changes.  This ensures
  # that a subsequent build re-runs clang-tidy on all sources even if they
  # do not otherwise need to be recompiled.  Nothing actually uses this
  # definition.  We add it to targets on which we run clang-tidy just to
  # get the build dependency on the .clang-tidy file.
  file(SHA1 ${CMAKE_CURRENT_SOURCE_DIR}/.clang-tidy clang_tidy_sha1)
  set(CLANG_TIDY_DEFINITIONS "CLANG_TIDY_SHA1=${clang_tidy_sha1}")
  unset(clang_tidy_sha1)

endif()
configure_file(.clang-tidy .clang-tidy COPYONLY)
