This package provides async features to the Symfony (+4.3) Kernel. This implementation uses ReactPHP Promise library and paradigm for this purposes.
Some first steps for you!
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In order to run the tests locally you must use one of the following snippet
composer update -n --prefer-dist
rm -Rf var/*
php vendor/bin/phpunit --testsuite=base --exclude-group=with-filesystem
Please note: phpunit caches the compiled container when it runs. Therefore, make sure to clear the cache from ./var/test, on any modification that causes the container to change.