Before:
  runtime ale_linters/dockerfile/hadolint.vim

After:
  call ale#linter#Reset()

Execute(The hadolint handler should handle an empty string response):
  AssertEqual
  \ [],
  \ ale_linters#dockerfile#hadolint#Handle(bufnr(''), [])

Execute(The hadolint handler should handle a normal example):
  AssertEqual
  \ [
  \   {
  \     'lnum': 1,
  \     'col': 0,
  \     'type': 'W',
  \     'text': "Always tag the version of an image explicitly",
  \     'detail': "DL3006 ( https://github.com/hadolint/hadolint/wiki/DL3006 )\n\nAlways tag the version of an image explicitly",
  \   },
#  \   {
#  \     'lnum': 2,
#  \     'col': 0,
#  \     'type': 'E',
#  \     'text': "MAINTAINER is deprecated",
#  \     'detail': "DL4000 ( https://github.com/hadolint/hadolint/wiki/DL4000 )\n\nMAINTAINER is deprecated",
#  \   },
#  \   {
#  \     'lnum': 4,
#  \     'col': 0,
#  \     'type': 'W',
#  \     'text': "Specify version with `yum install -y <package>-<version>`.",
#  \     'detail': "DL3033 ( https://github.com/hadolint/hadolint/wiki/DL3033 )\n\nSpecify version with `yum install -y <package>-<version>`.",
#  \   },
#  \   {
#  \     'lnum': 12,
#  \     'col': 0,
#  \     'type': 'W',
#  \     'text': "In POSIX sh, brace expansion is undefined.",
#  \     'detail': "SC2039 ( https://github.com/koalaman/shellcheck/wiki/SC2039 )\n\nIn POSIX sh, brace expansion is undefined.",
#  \   },
  \ ],
  \ ale_linters#dockerfile#hadolint#Handle(bufnr(''), [
  \ '/dev/stdin:1 DL3006 warning: Always tag the version of an image explicitly',
#  \ '/dev/stdin:2 DL4000 error: MAINTAINER is deprecated',
#  \ '/dev/stdin:4 DL3033 warning: Specify version with `yum install -y <package>-<version>`.',
#  \ '/dev/stdin:12 SC2039 warning: In POSIX sh, brace expansion is undefined.'
  \ ])