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