Is `create_test_data()` public API?

We want to encourage people to use and extend xarray, and we already provide testing functions as public API to help with this.

One function I keep using when writing code which uses xarray is xarray.tests.test_dataset.create_test_data(). This is very useful for quickly writing tests for the same reasons that it's useful in xarray's internal tests, but it's not explicitly public API. This means that there's no guarantee it won't change/disappear, which is not ideal if you're trying to write a test suite for separate software. But so many tests in xarray rely on it that presumably it's not going to get changed.

Is there any reason why it shouldn't be public API? Is there something I should use instead?

Start by reviewing the public-API status of xarray.tests.test_dataset.create_test_data() and the existing testing-function guidance referenced in the issue. Done means the project has a documented decision about whether this helper is public API, including what external test authors should use or expect.