KeyError: 'execution_count'

[kernc]

Attached minimal Jupyter notebook (strip ".txt"), given the following two commands, applied in series, results in the following error:

$ jupytext --to py error\ example2.ipynb
$ jupytext --test --update --to ipynb error\ example2.py

Traceback (most recent call last):
  File "/home/user/testing/venv/bin/jupytext", line 11, in <module>
    sys.exit(jupytext())
  File "/home/user/testing/venv/lib/python3.5/site-packages/jupytext/cli.py", line 129, in jupytext
    preserve_outputs=args.update)
  File "/home/user/testing/venv/lib/python3.5/site-packages/jupytext/cli.py", line 38, in convert_notebook_files
    test_round_trip_conversion(notebook, ext, preserve_outputs)
  File "/home/user/testing/venv/lib/python3.5/site-packages/jupytext/compare.py", line 88, in test_round_trip_conversion
    test_outputs=True)
  File "/home/user/testing/venv/lib/python3.5/site-packages/jupytext/compare.py", line 65, in compare_notebooks
    ref_cell = filtered_cell(ref_cell, preserve_outputs=test_outputs)
  File "/home/user/testing/venv/lib/python3.5/site-packages/jupytext/compare.py", line 16, in filtered_cell
    filtered['execution_count'] = cell['execution_count']
KeyError: 'execution_count'

error example2.ipynb.txt

Jupytext 0.6.5

[mwouts]

Thanks @kernc for reporting this. This is very useful. Let me try to turn your example into an additional test...

[mwouts]

The fix is on branch v0.7.0, but that branch is not stable yet, so I do not recommend that you use it now. Please wait a few more days before I can release it... Thanks

[mwouts]

A prerelease is available. Try it with:

pip install jupytext==0.7.0rc0

[kernc]

Verified works great. Thanks!