MRG+1: BUG: info['bads'] order shouldn't matter in write_evokeds()

doc/changes/latest.inc

@@ -105,12 +105,14 @@ Changelog
 
 - Add ``'auto'`` option to :meth:`mne.preprocessing.ICA.find_bads_ecg` to automatically determine the threshold for CTPS method by `Yu-Han Luo`_
 
-- Add a ``notebook`` 3d backend for visualization in jupyter notebook with :func:`mne.viz.set_3d_backend` by`Guillaume Favelier`_
+- Add a ``notebook`` 3d backend for visualization in jupyter notebook with :func:`mne.viz.set_3d_backend` by `Guillaume Favelier`_
 
 - Add support for reading and writing surfaces in Wavefront .obj format to the :func:`mne.read_surface` and :func:`mne.write_surface` by `Marijn van Vliet`_
 
 - Add tutorial on how to manually fix BEM meshes in Blender by `Marijn van Vliet`_ and `Ezequiel Mikulan`_
 
+- :func:`mne.write_evokeds` will now accept :class:`mne.Evoked` objects with differing channel orders in ``info['bads']``, which would previously raise an exception by `Richard Höchenberger`_
+
 Bug
 ~~~
 

mne/epochs.py

@@ -2908,7 +2908,7 @@ def _compare_epochs_infos(info1, info2, name):
     info2._check_consistency()
     if info1['nchan'] != info2['nchan']:
         raise ValueError(f'{name}.info[\'nchan\'] must match')
-    if info1['bads'] != info2['bads']:
+    if set(info1['bads']) != set(info2['bads']):
         raise ValueError(f'{name}.info[\'bads\'] must match')
     if info1['sfreq'] != info2['sfreq']:
         raise ValueError(f'{name}.info[\'sfreq\'] must match')

mne/tests/test_evoked.py

@@ -208,6 +208,15 @@ def test_io_evoked(tmpdir):
     with pytest.warns(RuntimeWarning, match='-ave.fif'):
         read_evokeds(fname2)
 
+    # test writing when order of bads doesn't match
+    fname3 = tmpdir.join('test-bad-order-ave.fif')
+    condition = 'Left Auditory'
+    ave4 = read_evokeds(fname, condition)
+    ave4.info['bads'] = ave4.ch_names[:3]
+    ave5 = ave4.copy()
+    ave5.info['bads'] = ave4.info['bads'][::-1]
+    write_evokeds(fname3, [ave4, ave5])
+
     # constructor
     pytest.raises(TypeError, Evoked, fname)