CocoaPods/CocoaPods — pull request #2917 by segiddins (2014-12-07 22:01:31+00:00)
Title: Validate that a specification's `public_header_files` and `private_header_files` file patterns only match header files.

Also, validate that all file patterns, if given, match at least one file.

Closes https://github.com/CocoaPods/CocoaPods/issues/2914.