Before:
  Save g:ale_buffer_info

  let g:ale_buffer_info = {}

  let g:expected_loclist = [{
  \ 'bufnr': bufnr('%'),
  \ 'lnum': 2,
  \ 'vcol': 0,
  \ 'col': 3,
  \ 'text': 'foo bar',
  \ 'type': 'E',
  \ 'nr': -1,
  \ 'pattern': '',
  \ 'valid': 1,
  \}]

  function! ToggleTestCallback(buffer, output)
    return [{
    \ 'bufnr': a:buffer,
    \ 'lnum': 2,
    \ 'vcol': 0,
    \ 'col': 3,
    \ 'text': join(split(a:output[0])),
    \ 'type': 'E',
    \ 'nr': -1,
    \}]
  endfunction

  call ale#linter#Define('foobar', {
  \ 'name': 'testlinter',
  \ 'callback': 'ToggleTestCallback',
  \ 'executable': has('win32') ? 'cmd' : 'echo',
  \ 'command': 'echo foo bar',
  \})

After:
  Restore

  unlet! g:expected_loclist

  let g:ale_buffer_info = {}
  call ale#linter#Reset()

  delfunction ToggleTestCallback

Given foobar (Some imaginary filetype):
  foo
  bar
  baz

Execute(ALELint should run the linters):
  AssertEqual 'foobar', &filetype

  ALELint
  call ale#engine#WaitForJobs(2000)

  if !has('nvim')
    " Sleep so the delayed list function can run.
    " This breaks the tests in NeoVim for some reason.
    sleep 1ms
  endif

  " Check the loclist
  AssertEqual g:expected_loclist, getloclist(0)