Is that server variable always going to be set? If it's not we will get an error there.

I've included @timacdonald's suggestion on how to delete the files. Now we can be sure none of the cached files can give us any trouble.

I've also refactored the bootstrap file as a PHPunit extension, this has the following benefits:

• We can now reuse the CreatesApplication trait
• We now delete the cached files after the last tests, instead of before all tests (which means they are never left on the disk, and that IDEs wont try to index them)
• It gives users a convenient place to put additional PHPunit hooks

I think this should probably be 2 PRs so discussion can happen independently for the two different changes, i.e.

1. to remove the cached files before the test run with....

array_map('unlink', glob('bootstrap/cache/*.phpunit.php'));

2. Refactoring to the extension.

But while it is here - a couple of thoughts on this approach:

We now delete the cached files after the last tests, instead of before all tests (which means they are never left on the disk, and that IDEs wont try to index them)

This isn't really an issue. The files are .gitignored and before the introduction of this feature, running your test suite would already generate packages.php and services.php.

We will also have to check how this plays with parallel test runners, i.e. that it only runs the extension hooks once per run and not once per thread.

So, is this ready to merge?

I think this PR can be merged. I'm pretty sure it works just like the old code, and it solves the problem described in this issue.

Like @timacdonald said, i don't know if these hooks work with parallel test runners. But since these hooks are normal phpunit features, i'm not sure if this is something we should worry about.

Looks like ParaTest is hitting some issues due to its multi threaded-ness, but I have a solution that I think can just go in the docs. Will send a follow up PR to the docs about it.

p.s. @SjorsO I dig the extension over the plain bootstrap file. Nice being able to have a specific before and after hooks.