When I run tests with PhpUnit on a new package I'm creating for Laravel, it generates the file .phpunit.result.cache.
What to do with that? Do I add it to my .gitignore file or not?
I'm using PHPUnit 8.0.4
This file helps PHPUnit remember which tests previously failed, which can speed up your testing flow if you only re-run failed tests during development. This is useful for test-driven workflows in which you have configured tests to run automatically, such as on file save, and the same collection of tests is being run repeatedly.
It is also a good idea to add the cache file .phpunit.result.cache to your .gitignore so that it does not end up being committed to your repository.
If you would prefer not to generate the file then you can run phpunit with the --do-not-cache-result option, as pointed out by @Slack Undertow in the comments. This might be desired when running tests as part of a build pipeline, for example. Or, as @codekandis pointed out, the same option is available as the cacheResult attribute in phpunit.xml.