phpunit.xml

<?xml version="1.0" encoding="UTF-8"?>
<phpunit 
  backupGlobals="false"
  backupStaticAttributes="false"
  bootstrap="vendor/autoload.php"
  colors="true"
  convertErrorsToExceptions="true"
  convertNoticesToExceptions="true"
  convertWarningsToExceptions="true"
  processIsolation="false"
  stopOnFailure="false" >
<testsuites>
  <testsuite name="Your package's test suit">
    <directory>./tests/</directory>
  </testsuite>
</testsuites>
</phpunit>