Before:
  function! GenerateResults(buffer, output)
    return [
    \ {
    \   'lnum': 1,
    \   'col': 1,
    \   'type': 'E',
    \   'text': 'foo',
    \ },
    \ {
    \   'lnum': 2,
    \   'col': 1,
    \   'type': 'W',
    \   'text': 'bar',
    \ },
    \ {
    \   'lnum': 3,
    \   'col': 5,
    \   'type': 'E',
    \   'text': 'wat',
    \ },
    \]
  endfunction

  call ale#linter#Define('testft', {
  \ 'name': 'x',
  \ 'executable': 'echo',
  \ 'command': 'echo',
  \ 'callback': 'GenerateResults',
  \})
  highlight link SomeOtherGroup SpellBad

After:
  unlet! g:items

  delfunction GenerateResults
  call ale#linter#Reset()
  let g:ale_buffer_info = {}
  call clearmatches()
  highlight clear SomeOtherGroup

Given testft(A Javscript file with warnings/errors):
  foo
  bar
  baz wat
  line four

Execute(Highlights should be set when a linter runs):
  call ale#Lint()
  call ale#engine#WaitForJobs(2000)

  AssertEqual
  \ [
  \   {'group': 'ALEError', 'id': 4, 'priority': 10, 'pos1': [1, 1, 1]},
  \   {'group': 'ALEWarning', 'id': 5, 'priority': 10, 'pos1': [2, 1, 1]},
  \   {'group': 'ALEError', 'id': 6, 'priority': 10, 'pos1': [3, 5, 1]}
  \ ],
  \ getmatches()

  AssertEqual [[4], [5], [6]], map(copy(g:ale_buffer_info[bufnr('')].loclist), 'v:val.match_id_list')

Execute(Existing highlights should be kept):
  call matchaddpos('ALEError', [[1, 2, 1]], 10, 347)
  call matchaddpos('ALEWarning', [[2, 2, 1]], 10, 348)

  call ale#highlight#SetHighlights(bufnr('%'), [
  \ {'bufnr': bufnr('%'), 'match_id_list': [347], 'type': 'E', 'lnum': 1, 'col': 2},
  \ {'bufnr': bufnr('%'), 'match_id_list': [348], 'type': 'W', 'lnum': 2, 'col': 2},
  \ {'bufnr': bufnr('%'), 'type': 'E', 'lnum': 3, 'col': 2},
  \ {'bufnr': bufnr('%'), 'type': 'W', 'lnum': 4, 'col': 1},
  \])

  AssertEqual
  \ [
  \   {'group': 'ALEError', 'id': 347, 'priority': 10, 'pos1': [1, 2, 1]},
  \   {'group': 'ALEWarning', 'id': 348, 'priority': 10, 'pos1': [2, 2, 1]},
  \   {'group': 'ALEError', 'id': 7, 'priority': 10, 'pos1': [3, 2, 1]},
  \   {'group': 'ALEWarning', 'id': 8, 'priority': 10, 'pos1': [4, 1, 1]},
  \ ],
  \ getmatches()

" This test is important for preventing ALE from showing highlights for
" the wrong files.
Execute(Highlights set by ALE should be removed when buffer cleanup is done):
  call ale#engine#InitBufferInfo(bufnr('%'))

  call ale#highlight#SetHighlights(bufnr('%'), [
  \ {'bufnr': bufnr('%'), 'type': 'E', 'lnum': 3, 'col': 2},
  \])

  AssertEqual
  \ [{'group': 'ALEError', 'id': 9, 'priority': 10, 'pos1': [3, 2, 1]}],
  \ getmatches()

  call ale#cleanup#Buffer(bufnr('%'))

  AssertEqual [], getmatches()

Execute(Highlights should be cleared when buffers are hidden):
  call ale#engine#InitBufferInfo(bufnr('%'))
  let g:ale_buffer_info[bufnr('%')].loclist =  [
  \ {'bufnr': bufnr('%'), 'type': 'E', 'lnum': 3, 'col': 2},
  \]
  call ale#highlight#SetHighlights(
  \ bufnr('%'),
  \ g:ale_buffer_info[bufnr('%')].loclist
  \)

  AssertEqual 1, len(getmatches()), 'The highlights weren''t initially set!'

  call ale#highlight#BufferHidden(bufnr('%'))

  AssertEqual 0, len(getmatches()), 'The highlights weren''t cleared!'

  call ale#highlight#UpdateHighlights()

  AssertEqual 1, len(getmatches()), 'The highlights weren''t set again!'

Execute(Only ALE highlights should be restored when buffers are restored):
  call ale#engine#InitBufferInfo(bufnr('%'))
  let g:ale_buffer_info[bufnr('%')].loclist =  [
  \ {'bufnr': bufnr('%'), 'type': 'E', 'lnum': 3, 'col': 2},
  \]
  call ale#highlight#SetHighlights(
  \ bufnr('%'),
  \ g:ale_buffer_info[bufnr('%')].loclist
  \)

  call matchaddpos('SomeOtherGroup', [[1, 1, 1]])

  " We should have one more match here.
  AssertEqual 2, len(getmatches()), 'The highlights weren''t initially set!'

  call ale#highlight#BufferHidden(bufnr('%'))

  AssertEqual 0, len(getmatches()), 'The highlights weren''t cleared!'

  call ale#highlight#UpdateHighlights()

  " Only our matches should appear again.
  AssertEqual 1, len(getmatches()), 'The highlights weren''t set again!'

Execute(Higlight end columns should set an appropriate size):
  call ale#highlight#SetHighlights(bufnr('%'), [
  \ {'bufnr': bufnr('%'), 'type': 'E', 'lnum': 3, 'col': 2, 'end_col': 5},
  \ {'bufnr': bufnr('%'), 'type': 'W', 'lnum': 4, 'col': 1, 'end_col': 5},
  \])

  AssertEqual
  \ [
  \   {'group': 'ALEError', 'id': 15, 'priority': 10, 'pos1': [3, 2, 4]},
  \   {'group': 'ALEWarning', 'id': 16, 'priority': 10, 'pos1': [4, 1, 5]},
  \ ],
  \ getmatches()

Execute(Higlight end columns should set an appropriate size):
  call ale#highlight#SetHighlights(bufnr('%'), [
  \ {'bufnr': bufnr('%'), 'type': 'E', 'lnum': 1, 'col': 1},
  \ {'bufnr': bufnr('%'), 'type': 'E', 'lnum': 2, 'col': 1},
  \ {'bufnr': bufnr('%'), 'type': 'E', 'sub_type': 'style', 'lnum': 3, 'col': 1},
  \ {'bufnr': bufnr('%'), 'type': 'W', 'lnum': 4, 'col': 1},
  \ {'bufnr': bufnr('%'), 'type': 'W', 'lnum': 5, 'col': 1},
  \ {'bufnr': bufnr('%'), 'type': 'W', 'sub_type': 'style', 'lnum': 6, 'col': 1},
  \ {'bufnr': bufnr('%'), 'type': 'I', 'lnum': 7, 'col': 1},
  \])

  AssertEqual
  \ [
  \   {'group': 'ALEError', 'id': 17, 'priority': 10, 'pos1': [1, 1, 1]},
  \   {'group': 'ALEError', 'id': 18, 'priority': 10, 'pos1': [2, 1, 1]},
  \   {'group': 'ALEStyleError', 'id': 19, 'priority': 10, 'pos1': [3, 1, 1]},
  \   {'group': 'ALEWarning', 'id': 20, 'priority': 10, 'pos1': [4, 1, 1]},
  \   {'group': 'ALEWarning', 'id': 21, 'priority': 10, 'pos1': [5, 1, 1]},
  \   {'group': 'ALEStyleWarning', 'id': 22, 'priority': 10, 'pos1': [6, 1, 1]},
  \   {'group': 'ALEInfo', 'id': 23, 'priority': 10, 'pos1': [7, 1, 1]},
  \ ],
  \ getmatches()

Execute(Highlighting should support errors spanning many lines):
  let g:items = [
  \ {'bufnr': bufnr(''), 'type': 'E', 'lnum': 1, 'col': 1, 'end_lnum': 10, 'end_col': 3},
  \]

  call ale#highlight#SetHighlights(bufnr(''), g:items)

  " We should set 2 highlights for the item, as we can only add 8 at a time.
  AssertEqual
  \ [
  \   {
  \     'group': 'ALEError', 'id': 24, 'priority': 10, 'pos1': [1, 1, 1073741824],
  \     'pos2': [2], 'pos3': [3], 'pos4': [4], 'pos5': [5], 'pos6': [6],
  \     'pos7': [7], 'pos8': [8],
  \   },
  \   {
  \     'group': 'ALEError', 'id': 25, 'priority': 10,
  \     'pos1': [9], 'pos2': [10, 1, 3]
  \   },
  \ ],
  \ getmatches()

  AssertEqual [[24, 25]], map(copy(g:items), 'v:val.match_id_list')