wp-cli/wp-cli — pull request #1193 by danielbachhuber (2014-05-21 20:09:16+00:00)
Title: Throw warning on `wp rewrite flush` and no permalink structure

`wp rewrite flush` is successful, even when you don't have a permalink structure, and results in an empty rewrite rules option. To make this more user-friendly, let's throw a warning.