Speed up tests

[dfulu]

The tests take a long time to run on github. Some of this is unavoidable because we are doing end-to-end tests where we regrid NWP data and interpolate satellite data. However, we can likely reduce the time taken by the tests with more careful use of end-to-end and unit testing

[AswaniSahoo]

Hi @dfulu , I’m new to this repo and I’d like to help speed up the test suite (profiling → separating E2E from unit tests → CI improvements) and would love to contribute here.

Could you please:

• Assign me to this issue if that’s OK.
• Confirm whether any specific end‑to‑end tests must remain full‑data in PR CI (i.e., cannot be reduced or mocked).

[revaarathore11]

@dfulu @felix-e-h-p can i work on this issue ?
this is jow i am willing to solve this
1. Profiling slow tests
2. Converting unnecessary E2E tests → unit tests
3. Mocking heavy operations
4. Reducing dataset size for tests
5. Caching CI computations
6. Marking slow tests separately

[dfulu]

This is a open-ended issue and involves us deciding what we want from our test coverage to cover our operational use. This hasn't been marked with "contributions-welcome" and is an OCF internal issue