Jupytext: The JupyterLab extension for Jupytext only works for JupyterLab>=1.0

[mwouts]

Cf. #276

[mwouts]

I have reported the issue at https://github.com/jupyterlab/jupyterlab/issues/6764

[mwouts]

The dependency range for our extension is too large:

https://github.com/mwouts/jupytext/blob/b1b47ce59a0aa4e2f441ae3a37c72582afb29e62/packages/labextension/package.json#L32-L36

Consequently jupyter lab build picks the version 1.0 of @jupyterlab/application, which was released one week ago.

Maybe this means that I should prepare multiple versions of the extension: 0.19 to be used in JupyterLab beta, and 1.0 for use in JupyterLab 1.0? (the only difference being the dependencies...) I'll give it a try in the coming days.

[mwouts]

I have published a version 0.19.0 (that's the last version of jupyerlab on npm before 1.0) of the extension on npmjs. People who use Jupyter Lab 0.35 can install it with:

jupyter labextension install [email protected]

[mwouts]

In versions >=1.2.0 of Jupytext, the extension bundled with Jupytext will yield the following warning when Jupyter Lab < 1.0 is build:

[LabBuildApp] WARNING |
"[email protected]" is not compatible with the current JupyterLab
Conflicting Dependencies:
JupyterLab              Extension        Package
>=0.19.1 <0.20.0        >=1.0.0 <2.0.0   @jupyterlab/application
>=0.19.1 <0.20.0        >=1.0.0 <2.0.0   @jupyterlab/apputils
>=0.19.2 <0.20.0        >=1.0.0 <2.0.0   @jupyterlab/notebook

In that case the user should manually install the version 0.19 of the extension as documented above.