Before: call ale#assert#SetUpLinterTest('ruby', 'reek') After: call ale#assert#TearDownLinterTest() Execute(The reek callbacks should return the correct default values): WithChainResults ['reek 5.0.0'] AssertLinter 'reek', [ \ 'reek --version', \ 'reek -f json --no-progress --no-color --stdin-filename %s', \] " Try with older versions. call ale#semver#ResetVersionCache() WithChainResults ['reek 4.8.2'] AssertLinter 'reek', [ \ 'reek --version', \ 'reek -f json --no-progress --no-color', \] Execute(The reek version check should be cached): WithChainResults ['reek 5.0.0'] AssertLinter 'reek', [ \ 'reek --version', \ 'reek -f json --no-progress --no-color --stdin-filename %s', \] WithChainResults [] AssertLinter 'reek', [ \ '', \ 'reek -f json --no-progress --no-color --stdin-filename %s', \]