Before:
  runtime autoload/ale/handlers/fecs.vim

After:
  call ale#linter#Reset()

Execute(fecs should parse lines correctly):
  AssertEqual
  \ [
  \   {
  \     'lnum': 20,
  \     'col': 25,
  \     'text': 'Unexpected console statement.',
  \     'code': 'no-console',
  \     'type': 'W',
  \   },
  \   {
  \     'lnum': 24,
  \     'col': 36,
  \     'text': 'Missing radix parameter.',
  \     'code': 'radix',
  \     'type': 'E',
  \   },
  \   {
  \     'lnum': 25,
  \     'col': 6,
  \     'text': 'Missing static property value.',
  \     'type': 'E',
  \   },
  \ ],
  \ ale#handlers#fecs#Handle(347, [
  \   'fecs  WARN → line 20, col 25: Unexpected console statement.     (no-console)',
  \   'fecs ERROR → line 24, col 36: Missing radix parameter.  (radix)',
  \   'fecs ERROR → line 25, col 6: Missing static property value.',
  \ ])