Why is runInSeparateProces removed in v4?

[dingo-d]

I was running some tests where I want to set, and then unset the define('WP_ADMIN', true); constant (to simulate being on the admin side), and noticed my lines not being covered, and the last test where this should be false failing.

When debugging the tests, I noticed that the

/**
 * @runInSeparateProces
 * @preserveGlobalState disabled
 */

Annotations are no longer working and then noticed in the changelog that this is removed in V4.

This is a super useful feature for WordPress, seeing how it messes around with globals. Any idea when this feature will be re-added in v4?

[lucatume]

I will provide an immediate fix and an explanation.

Fix - use the uopz extension to define and undefined constants.

Explanation - the way the feature was implemented was brittle and never really satisfied me. Different versions of PHPUnit would handle things differently and it was a real pain to debug. My idea is to make an API around what is, currently, a test trait; that function is used over and over in the project tests to achieve the same effect: the code executed in the Closure passed to the LoopIsolation::assertInIsolation method is executed in a separate process and the result is returned.

To avoid delaying the release of version 4 further, I had resolved to remove the feature to readd it only if really requested.

Could you provide an example of the kind of code you're currently running that leverages the @runInSeparateProcess annotation?

[dingo-d]

The uopz is an extension that I'd have to download separately and prepare the CI for. Will have to take a closer look at it.

I'll also try to see about that test trait.

The thing that is bothering me mostly is that I have a test where I need to check if the user is on the admin or not, so I set define('WP_ADMIN', true);, which will set is_admin() function to return true (and I can check for my branches).

For example, I have a code:

public function myCallback()
{
	if(is_admin()) {
		return;
	}

	// Do some logic only on the front.
}

So to cover the actual business logic of the method I need to set the WP_ADMIN constant to false. And to cover the if branch it needs to be true.

So far I've 'circumvented' this by placing that test at the end of the class so that other tests before it will have the WP_ADMIN set to false, but the main problem is that the test classes after the one where I've put this constant to true, will now have that constant also set to true, thereby polluting the rest of the tests basically.

I've confirmed that by running a debug on the test class that gets executed after the test where the WP_ADMIN is set to true, and I can see the is_admin() returning true when I evaluate it.

[dingo-d]

The LoopIsolation trait is specific for the wp-browser test as far as I can see. Do you have a plan to maybe expose something like that as a module or something that can be used in userland testing?

[lucatume]

You can check the project own workflow files to see how to setup the extension in CI. To set it up locally, install the uopz extension as any other extension, but take care to set uopz.exit=1 to let termination functions work correctly.

Re LoopIsolation: yes, the idea would be to expose an API to make its use convenient in testing. Codeception 5 removed what little support there was to support the @runInSeparateProcess annotation (link), so I will explore what venues are there to support it in the project.

[lucatume]

I'm closing this discussion since the feature has been reintroduced.