How to recompile installed mix dependency (with :path option) without reconnecting runtime?

[linusdm]

I’ve got a mix project installed in a livebook with a :path dependency, to be able to reference modules from the mix project, like this:

root_path = Path.join(__DIR__, "..")

Mix.install(
  [
    {:my_app, path: root_path, env: :dev},
    ...
  ],
  config_path: Path.join(root_path, "config/config.exs"),
  lockfile: Path.join(root_path, "mix.lock")
)

Is there a way to recompile the project when there are code changes in the mix project, without reconnecting the livebook runtime? The turnaround time is quite big now, when reconnecting and running all previous code cells again.

Running IEx.Helpers.recompile() raises an error:

** (Mix.Error) Cannot access build without an application name, please ensure you are in a directory with a mix.exs file and it defines an :app name under the project configuration
    (mix 1.14.2) lib/mix.ex:513: Mix.raise/2

Using File.cd/1 before to change directory to the directory with the mix.exs file doesn't help either. So I don't think that's the way to go about it.

[josevalim]

It is not a possibility right now. We have plans to Mix.install/2 re-runnable but that will require changes in Elixir first.

[jonatanklosko]

Tip: the most convenient way to do this without moving back and forth is to restart the runtime with 00 and then run the focused cell with cmd + enter. If the cells themselves take long time, that's a separate issue.

Technically you could also do iex --sname project --cookie project -S mix, then use the attached runtime and do recompile in the console whenever needed (or IEx.Helpers.recompile() in Livebook). However, this way it's more burden if you need to actually restart the runtime and you can't add additional dependencies for the notebook.

[linusdm]

Those are great tips, thx! That list with shortcuts keeps getting better :)