Before:
  Save g:ale_completion_enabled
  Save g:ale_completion_delay
  Save g:ale_completion_max_suggestions
  Save &l:omnifunc
  Save &l:completeopt

  let g:ale_completion_enabled = 1
  let g:get_completions_called = 0
  let g:feedkeys_calls = []
  let g:fake_mode = 'i'

  let &l:completeopt = 'menu,menuone,preview,noselect,noinsert'

  runtime autoload/ale/util.vim

  function! ale#util#FeedKeys(string, mode) abort
    call add(g:feedkeys_calls, [a:string, a:mode])
  endfunction

  " Pretend we're in insert mode for most tests.
  function! ale#util#Mode(...) abort
    return g:fake_mode
  endfunction

  function! CheckCompletionCalled(expect_success) abort
    let g:get_completions_called = 0

    " We just want to check if the function is called.
    function! ale#completion#GetCompletions()
      let g:get_completions_called = 1
    endfunction

    let g:ale_completion_delay = 0
    call ale#completion#Queue()
    sleep 1m

    AssertEqual a:expect_success, g:get_completions_called
  endfunction

After:
  Restore

  unlet! g:fake_mode
  unlet! g:get_completions_called
  unlet! b:ale_old_omnifunc
  unlet! b:ale_old_completopt
  unlet! b:ale_completion_info
  unlet! b:ale_completion_response
  unlet! b:ale_completion_parser
  unlet! b:ale_complete_done_time

  delfunction CheckCompletionCalled

  " Stop any timers we left behind.
  " This stops the tests from failing randomly.
  call ale#completion#StopTimer()

  " Reset the function. The runtime command below should fix this, but doesn't
  " seem to fix it.
  function! ale#util#Mode(...) abort
    return call('mode', a:000)
  endfunction

  runtime autoload/ale/completion.vim
  runtime autoload/ale/util.vim

Execute(ale#completion#GetCompletions should be called when the cursor position stays the same):
  call CheckCompletionCalled(1)

Given typescript():
  let abc = y.
  let foo = ab
  let foo = (ab)

Execute(ale#completion#GetCompletions should not be called when the cursor position changes):
  call setpos('.', [bufnr(''), 1, 2, 0])

  " We just want to check if the function is called.
  function! ale#completion#GetCompletions()
    let g:get_completions_called = 1
  endfunction

  let g:ale_completion_delay = 0
  call ale#completion#Queue()

  " Change the cursor position before the callback is triggered.
  call setpos('.', [bufnr(''), 2, 2, 0])

  sleep 1m

  Assert !g:get_completions_called

Execute(ale#completion#GetCompletions should not be called if you switch to normal mode):
  let &l:completeopt = 'menu,preview'
  let g:fake_mode = 'n'

  " We just want to check if the function is called.
  function! ale#completion#GetCompletions()
    let g:get_completions_called = 1
  endfunction

  let g:ale_completion_delay = 0
  call ale#completion#Queue()

  sleep 1m

  Assert !g:get_completions_called

Execute(Completion should not be done shortly after the CompleteDone function):
  call CheckCompletionCalled(1)
  call ale#completion#Done()
  call CheckCompletionCalled(0)

Execute(ale#completion#Show() should remember the omnifunc setting and replace it):
  let &l:omnifunc = 'FooBar'

  call ale#completion#Show('Response', 'Parser')

  AssertEqual 'FooBar', b:ale_old_omnifunc
  AssertEqual 'ale#completion#OmniFunc', &l:omnifunc

Execute(ale#completion#Show() should remember the completeopt setting and replace it):
  let &l:completeopt = 'menu'

  call ale#completion#Show('Response', 'Parser')

  AssertEqual 'menu', b:ale_old_completopt
  AssertEqual 'menu,menuone,noselect,noinsert', &l:completeopt

Execute(ale#completion#Show() should set the preview option if it's set):
  let &l:completeopt = 'menu,preview'

  call ale#completion#Show('Response', 'Parser')

  AssertEqual 'menu,preview', b:ale_old_completopt
  AssertEqual 'menu,menuone,preview,noselect,noinsert', &l:completeopt

Execute(ale#completion#OmniFunc() should also remember the completeopt setting and replace it):
  let &l:completeopt = 'menu'

  call ale#completion#OmniFunc(0, '')

  AssertEqual 'menu', b:ale_old_completopt
  AssertEqual 'menu,menuone,noselect,noinsert', &l:completeopt

Execute(ale#completion#OmniFunc() should set the preview option if it's set):
  let &l:completeopt = 'menu,preview'

  call ale#completion#OmniFunc(0, '')

  AssertEqual 'menu,preview', b:ale_old_completopt
  AssertEqual 'menu,menuone,preview,noselect,noinsert', &l:completeopt

Execute(ale#completion#Show() should make the correct feedkeys() call):
  call ale#completion#Show('Response', 'Parser')

  AssertEqual [["\<C-x>\<C-o>", 'n']], g:feedkeys_calls

Execute(ale#completion#Show() shouldn't do anything if you switch back to normal mode):
  let &l:completeopt = 'menu,preview'
  let g:fake_mode = 'n'

  call ale#completion#Show('Response', 'Parser')

  AssertEqual 'menu,preview', &l:completeopt
  Assert !exists('b:ale_old_omnifunc')
  Assert !exists('b:ale_old_completopt')
  Assert !exists('b:ale_completion_response')
  Assert !exists('b:ale_completion_parser')
  AssertEqual [], g:feedkeys_calls

Execute(ale#completion#Show() should set up the response and parser):
  call ale#completion#Show('Response', 'Parser')

  AssertEqual 'Response', b:ale_completion_response
  AssertEqual 'Parser', b:ale_completion_parser

Execute(ale#completion#Done() should restore old omnifunc values):
  let b:ale_old_omnifunc = 'FooBar'

  call ale#completion#Done()

  " We reset the old omnifunc setting and remove the buffer variable.
  AssertEqual 'FooBar', &l:omnifunc
  Assert !has_key(b:, 'ale_old_omnifunc')

Execute(ale#completion#Done() should restore the old completeopt setting):
  let b:ale_old_completopt = 'menu'

  call ale#completion#Done()

  AssertEqual 'menu', &l:completeopt
  Assert !has_key(b:, 'ale_old_completopt')

Execute(ale#completion#Done() should leave settings alone when none were remembered):
  let &l:omnifunc = 'BazBoz'
  let &l:completeopt = 'menu'

  call ale#completion#Done()

  AssertEqual 'BazBoz', &l:omnifunc
  AssertEqual 'menu', &l:completeopt

Execute(The completion request_id should be reset when queuing again):
  let b:ale_completion_info = {'request_id': 123}

  let g:ale_completion_delay = 0
  call ale#completion#Queue()
  sleep 1m

  AssertEqual 0, b:ale_completion_info.request_id

Execute(b:ale_completion_info should be set up correctly when requesting completions):
  call setpos('.', [bufnr(''), 3, 14, 0])
  call ale#completion#GetCompletions()

  AssertEqual
  \ {
  \   'request_id': 0,
  \   'conn_id': 0,
  \   'column': 14,
  \   'line_length': 14,
  \   'line': 3,
  \   'prefix': 'ab',
  \ },
  \ b:ale_completion_info