plataformatec/devise — pull request #1563 by marioaquino (2012-01-11 21:00:07+00:00)
Title: Allow regex to avoid string conversion for parameter filtering

We've run into a problem where we want to do a case-insensitive username lookup. We cannot use the built-in case-insensitivity capabilities, because they do not preserve case on the username, which our customer requires.

This commit simply lets us pass a Regexp as a param filter, allowing us to implement the feature we require.