How can I enable IDE integration (autocomplete) for WordPress test suite

Question

When testing a theme or plugin, you can use WP-CLI to scaffold the test suite setup, wp scaffold plugin-test plugin.

So is there a good way to integrate an editor/IDE (VS Code in my case) so that autocompletion (method signatures, etc) works within the tests? Since the test library is installed in /tmp/ the editor is not indexing those files and thus thinks classes and functions are missing.

Answer 1

In order of preference:

1. composer require wp-phpunit/wp-phpunit --dev. Depending on the IDE you use you might need to mark the package in vendor/ as a source directory.
2. Each IDE allows you to add definitions from external libraries. In PHPStorm it's Settings → Languages & Frameworks → PHP → Include Path.
3. Just copy the files over to some directory in your project and exclude them with .gitignore (if you use Git for version control).