Phpunit has some functionality for raising flags for tests that might cause problems. "Risky" tests. This was previously strict mode which cased some problems but the more recent versions of phpunit provide more fine grained control. Such flags can help identify problematic tests before they cause problems.
Enable some sane strict flags but don't enforce any failures yet.
User interface changes
Beta phase evaluation
|Issue category||Bug because we decide to be strict but we are not.|
|Issue priority||Major because this was a regression and we decided to be strict|
|Disruption||Should be limited. Most phpunit tests do a good job already and we don't seem to be adding risky tests.|