scikit-learn/scikit-learn — pull request #4031 by amueller (2014-12-30 00:24:04+00:00)
Title: [WIP] fixes to check_scoring and regression tests. 

This changes the behavior of ``check_scoring``.
If scoring is provided, it MUST be used. Also, a scorer might not need predict, so that check is dropped.
Fixes remaining issues from #3848 and #2853.