Improved external test data file handling

[bourque]

This PR changes how external test data files are defined -- I moved the list (which has grown quite large and may continue to grow) to its own file which is then imported into conftest.py. I also added some CoDICE validation files so that they can be stored in S3 instead of within the repo.

Closes #1537

[Copilot]

Pull Request Overview

Moves the growing list of external test data file paths into a dedicated config file and updates fixtures and tests to use it.

• Extracted the external test data list into external_test_data_config.py
• Updated _download_external_data fixture in conftest.py to import and iterate over EXTERNAL_TEST_DATA
• Cleaned up test_codice_l1a.py by removing manual download calls and adjusting the fixture return type

Reviewed Changes

Copilot reviewed 20 out of 20 changed files in this pull request and generated 2 comments.

File	Description
imap_processing/tests/external_test_data_config.py	New config module listing external test data files
imap_processing/tests/conftest.py	Fixture now uses EXTERNAL_TEST_DATA, removed old helper method
imap_processing/tests/codice/test_codice_l1a.py	Fixture signature updated to return list[xr.Dataset]

Comments suppressed due to low confidence (2)

imap_processing/tests/conftest.py:110

• The docstring still refers to a test_data_paths parameter which no longer exists. Update it to describe that EXTERNAL_TEST_DATA is used directly.

    """This fixture downloads externally-located test data files into a specific

imap_processing/tests/codice/test_codice_l1a.py:121

• [nitpick] Ensure your project runs on a Python version that supports built-in generic annotations (list[xr.Dataset]), or switch to from typing import List if compatibility is needed.

def test_l1a_data() -> list[xr.Dataset]:

[tech3371]

LGTM

[tmplummer]

I am happy with this as is, but made one recommendation for a slight tweak to further reduce clutter in the new config file.

[tmplummer]

Overall, this looks like a nice improvement. I'm wondering if it would be worth taking it a step further to make the tuple for a single file contain (<s3_filename>, <parent_test_dir_relative_to_imap_module_dir>). That would clean up this configuration by removing the imap_module_directory as well as the target path filename. The later part would require that the filename remains the same when downloaded.

For this line, it would look like:

Suggested change

	("imap_codice_l0_raw_20241110_v001.pkts", imap_module_directory / "tests" / "codice" / "data" / "imap_codice_l0_raw_20241110_v001.pkts"),
	("imap_codice_l0_raw_20241110_v001.pkts", "tests/codice/data"),

[bourque]

Good idea, I like it.