[Error Fix] 'CMake find_package' 문제 해결(feat. MacOS Qt5 FindQt5.cmake)

# 문제 상황

'brew install qt5'로 qt5는 설치하였으나 find_package로 내부 파일을 찾지 못하여 다음과 같은 메시지가 떴다.

CMake Error at src/CMakeLists.txt:2 (find_package):
  By not providing "FindQt5.cmake" in CMAKE_MODULE_PATH this project has
  asked CMake to find a package configuration file provided by "Qt5", but
  CMake did not find one.

  Could not find a package configuration file provided by "Qt5" with any of
  the following names:

    Qt5Config.cmake
    qt5-config.cmake

  Add the installation prefix of "Qt5" to CMAKE_PREFIX_PATH or set "Qt5_DIR"
  to a directory containing one of the above files.  If "Qt5" provides a
  separate development package or SDK, be sure it has been installed.

# 해결 방안

% brew --prefix qt5
/opt/homebrew/opt/qt@5

CMakeLists.txt 파일에서 find_package 전에 CMAKE_PREFIX_PATH를 위의 경로로 지정하여 해당 패키지를 찾을 수 있도록 한다.

set(CMAKE_PREFIX_PATH "/opt/homebrew/opt/qt@5")
...
find_package(Qt5 COMPONENTS Widgets Charts DataVisualization REQUIRED)

# 참고

• [StackOverFlow] MacOS Sierra - cmake failed with qt5: https://stackoverflow.com/questions/40081327/macos-sierra-cmake-failed-with-qt5