Behat/Gherkin — comment on commit 79d3475337304c717335c82d7bd80bbcb6866ca7
File: src/Behat/Gherkin/Keywords/ArrayKeywords.php line 113
By stof:

btw, returning ``null`` will probably break the keyword dumper when trying to use ``explode`` on it. So if you want to keep the check in the methods, you should return an empty string otherwise.

And the question about the checks remains as ``step_types`` is not the only one skipping the check