composer/composer — pull request #3291 by boombatower (2014-09-21 05:51:26+00:00)
Title: Remove extra ? from repositories regex in config command.

This looks like a typo or perhaps the author thought you needed `?` on both sides of optional group? Either way in its current state the regex matches the following. The last one does not look intentional.

repositories.foo
repos.foo
repoitories.bar

The corrected regex does not match the last entry.