Before: call ale#assert#SetUpLinterTest('bicep', 'bicep') After: call ale#assert#TearDownLinterTest() Execute(The default command should be correct): if has('win32') AssertLinter 'bicep', ale#Escape('bicep') . ' build --outfile NUL %s' else AssertLinter 'bicep', ale#Escape('bicep') . ' build --outfile /dev/null %s' endif Execute(The executable should be configurable): let g:ale_bicep_bicep_executable = 'foobar' if has('win32') AssertLinter 'foobar', ale#Escape('foobar') . ' build --outfile NUL %s' else AssertLinter 'foobar', ale#Escape('foobar') . ' build --outfile /dev/null %s' endif