Before:
  call ale#assert#SetUpFixerTest('roc', 'roc_format')

After:
  call ale#assert#TearDownFixerTest()

Execute(The roc format callback should return the correct default values):
  AssertFixer {
  \    'command': 'roc format %t',
  \    'read_temporary_file': 1,
  \}

Execute(The roc format callback should allow a custom executable):
  let g:ale_roc_roc_format_executable = 'foo/bar'

  AssertFixer {
  \    'command': 'foo/bar format %t',
  \    'read_temporary_file': 1,
  \}