Cider should inject its own dependencies/plugins automatically at cider-jack-in

[phillord]

Currently, cider complains when the dependencies are wrong in profile.clj. I understand the reasons for this, but it would be nice if Cider offered the ability to update your profile for you.

Another possibility would be for cider to check whether pomegranate is present and if not, inject the correct dependencies. Don't know if that is possible with plugins, but worth thinking about.

This would be great for me when I am switching Emacs' -- sometimes using melpa-stable, sometimes melpa normal. Then I have to continually re-edit my profile.clj. Painful.

[benedekfazekas]

I've been thinking along the same lines (for clj-refactor as well) lately so +1

also we should be able to figure out if given setup uses lein or boot

[stardiviner]

+1 for this, don't want to continuously monitor version change update.

[Malabarba]

I mentioned this on slack. I'll be glad to provide this if lein (or boot) has a way to specify deps on the command line. Otherwise it would involve manually parsing the project.clj file in elisp, which is not something I'm super excited to do. =)

One thing that would be easier to do is to offer a "new project" command, which would create the project with the right deps. However, this wouldn't solve any of the complaints here.

[phillord]

I've been thinking about it -- a "cider shim" plugin which pulls the middleware into the JVM with pomegranate really seems possible to me. It should be possible to write it once and rarely update it. I guess it needs to inject both into the repl and the leiningen JVM?

I've been watching a new colleague of mine trying to install cider, and this step really isn't nice.

[benedekfazekas]

We do something like this in refactor-nrepl eg. add dependency to a running REPL. My worry is tho that these artifacts are not simple deps but nrepl middlewares there could be some extra steps to register them. No idea if this works dynamically.

[phillord]

I think it works. Can someone give this a go: https://github.com/phillord/plugin-inject

You launch with lein plugin-inject repl :headless and it pushes the nrepl middleware plugin in first, then passes execution to repl task. End result, cider works despite there not being any cider middleware plugin around.

Might not work for anyone else, but seems a reasonable start. It's only a few lines of code.

[Malabarba]

@phillord do you think it would be possible to specify the version of the cider middleware?

[phillord]

Hmmm, think I've made a mistake. I had an old "cider-nrepl" dependency left in my .lein. So, it's not working. Try again.

I think more generally this is a leiningen issue -- if cider could specify it's own profile.clj which was merged with the users, this would solve the problem. A shim is a bit of a cheap plastic solution (bad pun).

[expez]

It might be easier to just check if profiles.clj contains a matching version and if not offer to update the text specifying the version, before starting the repl at all. This would be far simpler than the proposed solutions so far.

I don't think we need more indirection (a shim) or any magic happening in the background (injecting the right stuff into a running repl).

[phillord]

I don't think would help with the new install. I agree, the shim is rather complex. Having support in lein would be the easiest.

[benedekfazekas]

this seems to be working for me:

lein update-in :plugins conj "[cider/cider-nrepl \"0.11.0-SNAPSHOT\"]" -- repl

[benedekfazekas]

it seems to me that boot has even better support for this via their boot.repl/*default-dependencies* and boot.repl/*default-middleware* atoms, see details and 1a765793

[benedekfazekas]

more on leiningen:

in fact it is doable even now with setting cider-lein-parameters:
(setq cider-lein-parameters "update-in :plugins conj \"[cider/cider-nrepl \\\"0.11.0-SNAPSHOT\\\"]\" -- repl")

so I guess we could introduce a variable listing all nrepl middleware plugins (so clj-refactor can add its own) and then update those in as plugins by default with perhaps an opt out config in case somebody wants to start up cider without this.

[Malabarba]

lein update-in :plugins conj "[cider/cider-nrepl "0.11.0-SNAPSHOT"]" -- repl

Nice! If it's as simple as that, I'd like to start using this as soon as the next release.
I've set a milestone so that we at least give it a try and see if it's feasible.