Given javascript (Some JavaScript with problems):
  var y = 3+3;
  var y = 3

Before:
  let g:expected_data = [
  \ {
  \   'lnum': 1,
  \   'bufnr': bufnr('%'),
  \   'vcol': 0,
  \   'linter_name': 'eslint',
  \   'nr': -1,
  \   'type': 'W',
  \   'col': 10,
  \   'text': 'Infix operators must be spaced. [Warning/space-infix-ops]',
  \ },
  \ {
  \   'lnum': 2,
  \   'bufnr': bufnr('%'),
  \   'vcol': 0,
  \   'linter_name': 'eslint',
  \   'nr': -1,
  \   'type': 'E',
  \   'col': 10,
  \   'text': 'Missing semicolon. [Error/semi]',
  \ }
  \]

After:
  unlet g:expected_data

Execute(The loclist should be updated after linting is done):
  call ale#Lint()
  call ale#engine#WaitForJobs(2000)

  AssertEqual ['' . bufnr('%')], keys(g:ale_buffer_info)
  AssertEqual g:expected_data, g:ale_buffer_info[bufnr('%')].loclist