Before: Save g:ale_pattern_options, g:ale_pattern_options_enabled After: Restore unlet! b:ale_enabled unlet! b:some_option Execute(Buffer variables should be set when filename patterns match): let g:ale_pattern_options = {'baz.*\.js': { \ 'ale_enabled': 1, \ 'some_option': 347, \}} silent! file foobar.js call ale#pattern_options#SetOptions() Assert !exists('b:ale_enabled') Assert !exists('b:some_option') silent! file bazboz.js call ale#pattern_options#SetOptions() AssertEqual 1, b:ale_enabled AssertEqual 347, b:some_option