Unify cookiecutters?

[ianhi]

Problem

The js and ts cookiecutters can easily get out of sync, for example the js cookiecutter uses widgets.register while the ts cookiecutter does not. Looking through them there are several PRs that apply to one but not the other, even if the same changes would apply equally. For instance the cookiecutters ought to have the same packaging, so PRs such as jupyter-widgets/widget-cookiecutter#87 will require duplicated effort.

Proposed Solution

Create a single cookiecutter that has an option to choose ts or js.

[jtpio]

Thanks @ianhi for opening this issue.

This also came up for the JupyterLab cookiecutters when updating the JS cookiecutter to the new distribution system: jupyterlab/extension-cookiecutter-js#33 (comment)

Now extension-cookiecutter-js and extension-cookiecutter-ts are very similar. It was briefly discussed in this lab dev meeting whether or not they should be a single cookiecutter: jupyterlab/frontends-team-compass#117 (comment) (although there hasn't been any decision on this yet).