Before:
  call ale#assert#SetUpLinterTest('elixir', 'mix')

  let g:env_prefix = has('win32')
  \ ? 'set MIX_BUILD_PATH=' . ale#Escape('TEMP_DIR') . ' && '
  \ : 'MIX_BUILD_PATH=' . ale#Escape('TEMP_DIR') . ' '

After:
  unlet! g:env_prefix

  call ale#assert#TearDownLinterTest()

Execute(The default mix command should be correct):
  call ale#test#SetFilename('elixir_paths/mix_project/lib/app.ex')

  AssertLinter 'mix',
  \ ale#path#CdString(ale#path#Simplify(g:dir . '/elixir_paths/mix_project'))
  \ . g:env_prefix
  \ . 'mix compile %s'

Execute(FindMixProjectRoot should detect the project root directory via mix.exs):
  silent execute 'file ' . fnameescape(g:dir . '/elixir_paths/mix_project/lib/app.ex')

  AssertEqual
  \ ale#path#Simplify(g:dir . '/elixir_paths/mix_project'),
  \ ale#handlers#elixir#FindMixProjectRoot(bufnr(''))

Execute(FindMixUmbrellaRoot should detect the umbrella root directory via mix.exs):
  silent execute 'file ' . fnameescape(g:dir . '/elixir_paths/umbrella_project/apps/app1/lib/app.ex')

  AssertEqual
  \ ale#path#Simplify(g:dir . '/elixir_paths/umbrella_project'),
  \ ale#handlers#elixir#FindMixUmbrellaRoot(bufnr(''))