The new version contains some improvements in handling mocks (https://github.com/sebastianbergmann/phpunit/issues/3602) and will help identify some existing issues in DBAL 3.0 tests:

There were 2 warnings:

1) Doctrine\Tests\DBAL\Driver\OCI8\OCI8StatementTest::testExecute with data set #0 (array('test', null, 'value'))
Method bindValue may not return value of type boolean

2) Doctrine\Tests\DBAL\Driver\OCI8\OCI8StatementTest::testExecute with data set #1 (array(null, 'test', 'value'))
Method bindValue may not return value of type boolean