Before:
  let g:testlinter1 = {'name': 'testlinter1', 'executable': 'testlinter1', 'command': 'testlinter1', 'callback': 'testCB1', 'output_stream': 'stdout'}
  let g:testlinter2 = {'name': 'testlinter2', 'executable': 'testlinter2', 'command': 'testlinter2', 'callback': 'testCB2', 'output_stream': 'stdout'}

  call ale#linter#Reset()
  let g:ale_linters = {}
  let g:ale_linter_aliases = {}

Execute (Define a linter):
  call ale#linter#Define('testft', g:testlinter1)
Then (Get the defined linter):
  AssertEqual [g:testlinter1], ale#linter#Get('testft')

Execute (Define a couple linters, filtering one):
  call ale#linter#Define('testft', g:testlinter1)
  call ale#linter#Define('testft', g:testlinter2)
  let g:ale_linters = {'testft': ['testlinter1']}
Then (Only the configured linter should be returned):
  AssertEqual [g:testlinter1], ale#linter#Get('testft')

Execute (Define a linter for a filetype, and create a filetype alias):
  call ale#linter#Define('testft1', g:testlinter1)
  let g:ale_linter_aliases = {'testft2': 'testft1'}
Then (Linters should be transparently aliased):
  AssertEqual [g:testlinter1], ale#linter#Get('testft2')

Execute (Define multiple linters, with filters and aliases):
  call ale#linter#Define('testft1', g:testlinter1)
  call ale#linter#Define('testft1', g:testlinter2)
  let g:ale_linters = {'testft1': ['testlinter1'], 'testft2': ['testlinter2']}
  let g:ale_linter_aliases = {'testft2': 'testft1'}
Then (Linters should be transparently filtered and aliased):
  AssertEqual [g:testlinter1], ale#linter#Get('testft1')
  AssertEqual [g:testlinter2], ale#linter#Get('testft2')

Execute (Define multiple linters for different filetypes):
  call ale#linter#Define('testft1', g:testlinter1)
  call ale#linter#Define('testft2', g:testlinter2)
Then (Linters for dot-seperated filetypes should be properly handled):
  AssertEqual [g:testlinter1, g:testlinter2], ale#linter#Get('testft1.testft2')

Execute (Try to load a linter from disk):
  AssertEqual [{'name': 'testlinter', 'output_stream': 'stdout', 'executable': 'testlinter', 'command': 'testlinter', 'callback': 'testCB'}], ale#linter#Get('testft')