Before: call ale#assert#SetUpLinterTest('python', 'pycodestyle') After: call ale#assert#TearDownLinterTest() Execute(The pycodestyle command callback should return default string): AssertLinter 'pycodestyle', ale#Escape('pycodestyle') . ' -' Execute(The pycodestyle command callback should allow options): let g:ale_python_pycodestyle_options = '--exclude=test*.py' AssertLinter 'pycodestyle', \ ale#Escape('pycodestyle') . ' --exclude=test*.py -' Execute(The pycodestyle executable should be configurable): let g:ale_python_pycodestyle_executable = '~/.local/bin/pycodestyle' AssertLinter '~/.local/bin/pycodestyle', \ ale#Escape('~/.local/bin/pycodestyle') . ' -' Execute(Setting executable to 'pipenv' appends 'run pycodestyle'): let g:ale_python_pycodestyle_executable = 'path/to/pipenv' AssertLinter 'path/to/pipenv', \ ale#Escape('path/to/pipenv') . ' run pycodestyle -' Execute(Pipenv is detected when python_pycodestyle_auto_pipenv is set): let g:ale_python_pycodestyle_auto_pipenv = 1 call ale#test#SetFilename('../test-files/python/pipenv/whatever.py') AssertLinter 'pipenv', \ ale#Escape('pipenv') . ' run pycodestyle -' Execute(Setting executable to 'poetry' appends 'run pycodestyle'): let g:ale_python_pycodestyle_executable = 'path/to/poetry' AssertLinter 'path/to/poetry', \ ale#Escape('path/to/poetry') . ' run pycodestyle -' Execute(Poetry is detected when python_pycodestyle_auto_poetry is set): let g:ale_python_pycodestyle_auto_poetry = 1 call ale#test#SetFilename('../test-files/python/poetry/whatever.py') AssertLinter 'poetry', \ ale#Escape('poetry') . ' run pycodestyle -'