Before:
  Save g:ale_pattern_options
  Save g:ale_pattern_options_enabled
  Save &filetype

After:
  Restore

  unlet! b:ale_enabled
  unlet! b:some_option

Execute(Buffer variables should be set when filename patterns match):
  let g:ale_pattern_options = {'baz.*\.js': {
  \ 'ale_enabled': 1,
  \ 'some_option': 347,
  \ '&filetype': 'pattern_option_set_filetype',
  \}}

  silent! file foobar.js

  call ale#pattern_options#SetOptions()

  Assert !exists('b:ale_enabled')
  Assert !exists('b:some_option')

  silent! file bazboz.js

  call ale#pattern_options#SetOptions()

  AssertEqual 1, b:ale_enabled
  AssertEqual 347, b:some_option
  AssertEqual 'pattern_option_set_filetype', &filetype