Before:
  call ale#assert#SetUpLinterTest('nix', 'statix')

After:
  call ale#assert#TearDownLinterTest()

Execute(The statix command should be correct):
  AssertLinter 'statix', ale#Escape('statix') . ' check -o errfmt --stdin'

Execute(Additional statix options should be configurable):
  let g:ale_nix_statix_check_options = '--foobar'

  AssertLinter 'statix',
  \ ale#Escape('statix') . ' check -o errfmt --stdin --foobar'

Execute(The statix command should be configurable):
  let g:ale_nix_statix_check_executable = 'foo/bar'

  AssertLinter 'foo/bar', ale#Escape('foo/bar') . ' check -o errfmt --stdin'