Before:
  call ale#assert#SetUpLinterTest('php', 'phpmd')

After:
  call ale#assert#TearDownLinterTest()

Execute(Custom executables should be used for the executable and command):
  let g:ale_php_phpmd_executable = 'phpmd_test'

  AssertLinter 'phpmd_test',
  \ ale#Escape('phpmd_test')
  \ . ' %t text cleancode,codesize,controversial,design,naming,unusedcode --ignore-violations-on-exit'