Support html language

[technic]

Hi,
%%html cell magic is not converted to py:percent correctly.
%%javascript, %%bash and others seem to work well.
I think we just need to add it to languages.py.

[mwouts]

Hello @technic , thanks for reporting this. I will cover this with an additional test, and hopefully fix it soon! By the way, are you aware of an explicit list of all languages that one can have in a notebook cell?

[technic]

Thanks!
@mwouts
Well, this is ipython cell magic, and in principle additional plugins, or users can add their custom languages.
So, unfortunately the complete list is not possible, but html is upstream. The upstream list is in the documentation.
Maybe we can have a metadata field as a hint for jupytext, that the field is not a valid python code (or is there one already?).

[mwouts]

Interesting! Well there is a large majority of cell magics for which the content of the cell should be escaped... I will have a look at this.

Maybe we can have a metadata field as a hint for jupytext, that the field is not a valid python code (or is there one already?).

Yes! You can tag your cells with the active="ipynb" metadata, as documented here.

[mwouts]

I plan to do the following

1. In the percent and light format, comment out all cells that start with a cell magics. @dsblank , are you aware of any cell magic that should not turn the cell into an inactive one in scripts?
2. In the hydrogen format, cells magics should appear verbatim in the text representation. I have tested a few of them and they all work!

[mwouts]

1. In the percent and light format, comment out all cells that start with a cell magics. @dsblank , are you aware of any cell magic that should not turn the cell into an inactive one in scripts?

I found one: %%time! So I will still check that the cell magic is a Jupyter language, and just allow html and latex there...

[mwouts]

Hello @technic , I expect this to be fixed in the latest RC:

pip install jupytext==1.0.0-rc5

Can you please test and confirm that it now works as expected? Thanks