Before: call ale#assert#SetUpLinterTest('asm', 'gcc') call ale#test#SetFilename('test.cpp') let b:command_tail = ' -x assembler' \ . ' -o ' . (has('win32') ? 'nul': '/dev/null') \ . '-iquote %s:h' \ . ' -Wall -' After: unlet! b:command_tail call ale#assert#TearDownLinterTest() Execute(The default command should be correct): AssertLinter 'gcc', ale#Escape('gcc') . b:command_tail Execute(The executable should be configurable): let b:ale_asm_gcc_executable = 'foobar' AssertLinter 'foobar', ale#Escape('foobar') . b:command_tail