Before:
  call ale#assert#SetUpLinterTest('c', 'clangd')

  function! Hook1(buffer)
    return 'abc123'
  endfunction

After:
  let g:ale_lsp_root = {}
  unlet! b:ale_lsp_root
  delfunction Hook1

  call ale#assert#TearDownLinterTest()

Execute(The buffer-specific variable can be a string):
  let b:ale_lsp_root = '/some/path'
  call ale#test#SetFilename('other-file.c')

  AssertLSPProject '/some/path'

Execute(The buffer-specific variable can be a dictionary):
  let b:ale_lsp_root = {'clangd': '/some/path', 'golangserver': '/other/path'}
  call ale#test#SetFilename('other-file.c')

  AssertLSPProject '/some/path'

Execute(The buffer-specific variable can have funcrefs):
  let b:ale_lsp_root = {'clangd': function('Hook1'), 'golangserver': '/path'}
  call ale#test#SetFilename('other-file.c')

  AssertLSPProject 'abc123'

Execute(The global variable can be a dictionary):
  let g:ale_lsp_root = {'clangd': '/some/path', 'golangserver': '/other/path'}
  call ale#test#SetFilename('other-file.c')

  AssertLSPProject '/some/path'

Execute(The global variable can have funcrefs):
  let g:ale_lsp_root = {'clangd': function('Hook1'), 'golangserver': '/path'}
  call ale#test#SetFilename('other-file.c')

  AssertLSPProject 'abc123'

Execute(The buffer-specific variable overrides the global variable):
  let b:ale_lsp_root = {'clangd': '/some/path', 'golangserver': '/other/path'}
  let g:ale_lsp_root = {'clangd': '/not/this/path', 'golangserver': '/elsewhere'}
  call ale#test#SetFilename('other-file.c')

  AssertLSPProject '/some/path'

Execute(The global variable is queried if the buffer-specific has no value):
  let b:ale_lsp_root = {'golangserver': '/other/path'}
  let g:ale_lsp_root = {'clangd': '/some/path', 'golangserver': '/elsewhere'}
  call ale#test#SetFilename('other-file.c')

  AssertLSPProject '/some/path'

Execute(No path should be returned by default):
  call ale#test#SetFilename(tempname() . '/other-file.c')

  AssertLSPProject ''