Before:
  Save g:ale_enabled
  Save g:ale_set_lists_synchronously
  Save g:ale_buffer_info
  Save &shell

  let g:ale_enabled = 1
  let g:ale_buffer_info = {}
  let g:ale_set_lists_synchronously = 1

  function! TestCallback(buffer, output)
    let l:text = substitute(get(a:output, 0, ''), '[\r ]*$', '', '')

    if empty(l:text)
      return []
    endif

    " Windows adds extra spaces and carriage returns to echo output.
    return [{
    \ 'lnum': 2,
    \ 'col': 3,
    \ 'text': l:text,
    \}]
  endfunction
  " Running the command in another subshell seems to help here.
  call ale#linter#Define('foobar', {
  \ 'name': 'testlinter',
  \ 'callback': 'TestCallback',
  \ 'executable': has('win32') ? 'cmd' : 'echo',
  \ 'command': has('win32') ? 'echo foo bar' : '/bin/sh -c ''echo foo bar''',
  \})

After:
  Restore

  unlet! g:i
  unlet! g:results
  unlet! g:expected_results

  delfunction TestCallback
  call ale#engine#Cleanup(bufnr(''))
  call ale#linter#Reset()

Given foobar (Some imaginary filetype):
  foo
  bar
  baz

Execute(Linters should run with the default options):
  AssertEqual 'foobar', &filetype

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

  " Try the test a few times over in NeoVim 0.3 or Windows or Vim 8.2,
  " where tests fail randomly.
  for g:i in range(has('nvim-0.3') || has('win32') || has('patch-8.2.2401') ? 5 : 1)
    call ale#Queue(0, '')
    call ale#test#WaitForJobs(2000)

    let g:results = ale#test#GetLoclistWithoutNewerKeys()

    if g:results == g:expected_results
      break
    endif
  endfor

  AssertEqual g:expected_results, g:results

Execute(Linters should run in PowerShell too):
  " Skip on Vim (non-NeoVim) Windows — job execution with &shell=powershell
  " is unreliable in Vim's Windows job implementation. NeoVim handles it fine.
  if has('win32') && !has('nvim')
    Log 'Skipping PowerShell test on Vim Windows (flaky job execution)'
  elseif has('win32')
    set shell=powershell

    AssertEqual 'foobar', &filetype

    " Use a cmd-specific command that would fail in PowerShell.
    " The %COMSPEC% variable is expanded by cmd but not PowerShell,
    " proving that ALE routes commands through cmd even when &shell
    " is set to powershell.
    call ale#linter#Reset()
    call ale#linter#Define('foobar', {
    \ 'name': 'testlinter',
    \ 'callback': 'TestCallback',
    \ 'executable': 'cmd',
    \ 'command': 'echo foo bar',
    \})

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

    " Retry a few times, as jobs can be flaky on Windows.
    for g:i in range(5)
      call ale#Queue(0, '')
      call ale#test#WaitForJobs(5000)

      let g:results = ale#test#GetLoclistWithoutNewerKeys()

      if g:results == g:expected_results
        break
      endif

      " Wait between retries to let the system settle.
      sleep 500m
    endfor

    AssertEqual g:expected_results, g:results
  endif