In repo2docker we install jupyterlab for users as well as add some extensions. This works well until a repository lists
jupyterlab as a dependency in its
environment.yml. Then the user is greeted with a message that jupyterlab needs building because of extensions.
An example is https://mybinder.org/v2/gh/alanderex/pydata-pandas-workshop/master?urlpath=lab where we get told we need to build lab because of nbdime and offlinenotebooks.
I think this is because repo2docker installs jupyterlab, then builds extensions and then (later) updates jupyterlab because it is mentioned in the
Is there a command-line tool we could run as part of repo2docker after installing all the user specified packages to detect if lab needs rebuilding?