Before:
  Save g:ale_haskell_ghc_options

  unlet! g:ale_haskell_ghc_options
  unlet! b:ale_haskell_ghc_options

  runtime ale_linters/haskell/ghc.vim

After:
  Restore
  unlet! b:ale_haskell_ghc_options
  call ale#linter#Reset()

Execute(The options should be used in the command):
  AssertEqual
  \ 'ghc -fno-code -v0 %t',
  \ ale_linters#haskell#ghc#GetCommand(bufnr(''))

  let b:ale_haskell_ghc_options = 'foobar'

  AssertEqual
  \ 'ghc foobar %t',
  \ ale_linters#haskell#ghc#GetCommand(bufnr(''))