Before: Save g:typescript_tslint_executable Save g:typescript_tslint_config_path Save g:typescript_tslint_use_global unlet! g:typescript_tslint_executable unlet! g:typescript_tslint_config_path unlet! g:typescript_tslint_use_global runtime ale_linters/typescript/tslint.vim call ale#test#SetDirectory('/testplugin/test/command_callback') After: Restore call ale#test#RestoreDirectory() call ale#linter#Reset() Execute(The default tslint command should be correct): AssertEqual \ 'cd ''' . expand('%:p:h') . ''' && ' \ . 'tslint --format json %t', \ ale_linters#typescript#tslint#GetCommand(bufnr(''))