https://velog.io/@chappi/GO-Test-code-1%EC%9D%BC%EC%B0%A8-golang%EC%97%90%EC%84%9C-%ED%85%8C%EC%8A%A4%ED%8A%B8-%EC%BD%94%EB%93%9C-%EC%9E%91%EC%84%B1-coverage-%ED%99%95%EC%9D%B8-%EB%B0%A9%EB%B2%95
