This test suite runs tests the same way as `test/CommonMarkTestWeak.php`, but uses a cached set of CommonMark spec examples in `test/commonmark/`. It is executed along with Parsedown's default test suite and runs various CommonMark spec examples, which are expected to pass. If they don't pass, the Parsedown build fails. The intention of this test suite is to make sure, that previously passed CommonMark spec examples don't fail due to unwanted side-effects of code changes.
You can re-create the `test/commonmark/` directory by executing the PHPUnit group `update`. The test suite will then run `test/CommonMarkTestWeak.php` and create files with the Markdown source and the resulting HTML markup of all passed tests. The command to execute looks like the following:
$ phpunit --group update
