Before:
  runtime ale_linters/lua/luac.vim

After:
  call ale#linter#Reset()

Execute(The default command should be correct):
  AssertEqual ale#Escape('luac') . ' -p -',
  \ join(split(ale_linters#lua#luac#GetCommand(1)))

Execute(The luac executable should be configurable):
  let g:ale_lua_luac_executable = 'luac.sh'

  AssertEqual 'luac.sh', ale_linters#lua#luac#GetExecutable(1)
  AssertEqual ale#Escape('luac.sh') . ' -p -',
  \ join(split(ale_linters#lua#luac#GetCommand(1)))