Ondřej Mirtes have just announced the availability of PHPStan 0.10.6 with full support for PHP 7.3, which should be available in the next few days. The new release added support for is_countable(), JSON_THROW_ON_ERROR and array_key_first()/array_key_last(). In addition to a bug that prevent using symfony/console with broken exit code handling have been fixed.
PHPStan is a static analysis code for PHP, that allow you to discover bugs in your code without running it. It catches whole classes of bugs even before you write tests for the code. PHPStan moves PHP closer to compiled languages in the sense that the correctness of each line of the code can be checked before you run the actual line.
Update 6/12/2018 : Ondřej have just announced PHPStan pro edition, the SaaS version of PHPStan. The pro version will offer Instant feedback, support for legacy projects, latest updated version of PHPStan in the cloud, reporting errors directly on GitLab/GitHub, and automatic pull requests with fixes.
