FIX, TST: Try to get test_export_epochs_eeeglab passing again

[scott-huberty]

• Needs Handle special cases from MNE-Python jackz314/eeglabio#18

This test has been marked as failing for a while now:

mne-python/mne/export/tests/test_export.py

Lines 539 to 559 in 936bfae

	def test_export_epochs_eeglab(tmp_path, preload):
	"""Test saving an Epochs instance to EEGLAB's set format."""
	eeglabio = pytest.importorskip("eeglabio")
	raw, events = _get_data()[:2]
	raw.load_data()
	epochs = Epochs(raw, events, preload=preload)
	temp_fname = tmp_path / "test.set"
	# TODO: eeglabio 0.2 warns about invalid events
	if _compare_version(eeglabio.__version__, "==", "0.0.2-1"):
	ctx = _record_warnings
	else:
	ctx = nullcontext
	with ctx():
	epochs.export(temp_fname)
	epochs.drop_channels([ch for ch in ["epoc", "STI 014"] if ch in epochs.ch_names])
	epochs_read = read_epochs_eeglab(temp_fname, verbose="error") # head radius
	assert epochs.ch_names == epochs_read.ch_names
	cart_coords = np.array([d["loc"][:3] for d in epochs.info["chs"]]) # just xyz
	cart_coords_read = np.array([d["loc"][:3] for d in epochs_read.info["chs"]])
	assert_allclose(cart_coords, cart_coords_read)
	assert_array_equal(epochs.events[:, 0], epochs_read.events[:, 0]) # latency

Specifically right now the test on Line 559 is failing, i.e. the event latencies change across an IO trip.

The culprit is this block of code:

https://github.com/jackz314/eeglabio/blob/cf92efeb92f6ac45f28df50014b4f23ffe622d47/eeglabio/epochs.py#L104-L109

Basically, I think that eeglabio needs to be able to handle 1) the first_samp of a file and 2) the true number of trials before epochs get dropped. AFAICT, the direct path forward is to add a new parameter export_kwargs to epochs.export, that gets threaded to eeglabio.epochs.export_set. Then we can pass a first_samp and n_trials argument, which I am proposing to add over at jackz314/eeglabio#18

Reference issue (if any)

What does this implement/fix?

Additional information

[scott-huberty]

OK After 3 years, test_export_epochs_eeglab is passing : )

https://github.com/mne-tools/mne-python/actions/runs/17961850120/job/51086635335?pr=13428#step:19:3897

I am going to leave this PR in draft mode as a safeguard because I change the dependencies to point eeglabio to my branch over at https://github.com/jackz314/eeglabio/pull/18/files, which this PR depends on. The bulk of the fix is happening over there.

[larsoner]

Okay: https://pypi.org/project/eeglabio/0.1.2/

Should be able to revert the special-branch stuff and continue

[larsoner]

Other than one reST issue, LGTM +1 for merge! Feel free to commit the fix, mark as ready for review, and mark for merge-when-green @scott-huberty