Before:
  Save g:ale_haskell_hdevtools_executable
  Save g:ale_haskell_hdevtools_options

  unlet! g:ale_haskell_hdevtools_executable
  unlet! b:ale_haskell_hdevtools_executable
  unlet! g:ale_haskell_hdevtools_options
  unlet! b:ale_haskell_hdevtools_options

  runtime ale_linters/haskell/hdevtools.vim

  let b:command_tail = ' check -g -Wall -p %s %t'

After:
  Restore
  unlet! b:command_tail
  unlet! b:ale_haskell_hdevtools_executable
  unlet! b:ale_haskell_hdevtools_options
  call ale#linter#Reset()

Execute(The executable should be configurable):
  AssertEqual 'hdevtools', ale_linters#haskell#hdevtools#GetExecutable(bufnr(''))

  let b:ale_haskell_hdevtools_executable = 'foobar'

  AssertEqual 'foobar', ale_linters#haskell#hdevtools#GetExecutable(bufnr(''))

Execute(The executable should be used in the command):
  AssertEqual
  \ ale#Escape('hdevtools') . b:command_tail,
  \ ale_linters#haskell#hdevtools#GetCommand(bufnr(''))

  let b:ale_haskell_hdevtools_executable = 'foobar'

  AssertEqual
  \ ale#Escape('foobar') . b:command_tail,
  \ ale_linters#haskell#hdevtools#GetCommand(bufnr(''))