Add database ready check before calling $controller->doInit()

[timkung]

Affected Version

SS4.x

Description

In SapphireTest::start() there is a call to $controller->doInit();, however this causes issues if there are any DB calls in a custom init() method or if using the onBeforeInit hook as the DB is not ready at the point this is called.

Steps to Reproduce

Create a unit test for a class that is using the onBeforeInit hook and make a DB call in that method, e.g.

<?php

class TestMe extends DataExtension
{
    public function onBeforeInit()
    {
        // this will cause the unit test to fail as DB is not setup yet
        $pages = Page::get();
    }
}

[mlewis-everley]

This can happen outside of testing as well, for example I added some code to Controller::onBeforeInit() that gets from values from SiteConfig and it causes a Table not found error when the site first builds.