utils.merge() does not save filter information

[obergmartin]

When making a merged epoch object I would expect the high/low pass filter information to be the same. Or do I not understand the intended behaviour?

Here's some code that reproduces the result I'm finding:

data_path = Path(mne.datasets.sample.data_path(verbose=False))
sample_dir = data_path / "MEG" / "sample"
subjects_dir = data_path / "subjects"
raw_path = sample_dir / "sample_audvis_filt-0-40_raw.fif"
raw = mne.io.read_raw(raw_path).crop(10)
e = mne.make_fixed_length_epochs(raw, duration=1, preload=True)
# use the same data just for the example
e_merge = utils.merge(e,e)
print(e_merge.info['highpass'], e.info['highpass'])
print(e_merge.info['lowpass'], e.info['lowpass'])
# the output:
# (0.0, 0.10000000149011612)
# (75.07687377929688, 40.0)

I think the that can be fixed here:? https://github.com/ppsp-team/HyPyP/blob/8ecb507b40378aa839fa90d4a0b874a48b8e4162/hypyp/utils.py#L173

[obergmartin]

Is it safe to do this?

with info._unlock():
    info["lowpass"] = the_original_value