'jump to definition' not working on cider-connect with remote embed repl server.

[soulawaker]

I don't know it is bug or not, yet.

Expected behavior

Jumping to the definition that required by ns.

Actual behavior

Not jumping. symbol: prompted.

Steps to reproduce the problem

Add [cider/cider-nrepl "0.17.0-SNAPSHOT"] dependency to project.clj.
Add [cider.nrepl :refer [cider-nrepl-handler]] to ns in clj file that send its handler to an embed REPL server.
Find remote project folder and files by Emacs Tramp.
cider-connect on any remote project file to remote embed REPL server.
Connection established. 'cider-repl buffer' worked fine.
Try jump to definition in any function from required external namespace.
Failed and symbol: prompted.

This is extremely important! Providing us with a reliable way to reproduce
a problem will expedite its solution.

Environment & Version information

CIDER version information

0.17.0-SNAPSHOT (20171228.1254), nREPL 0.2.12
Clojure 1.8.0, Java 1.8.0_151

Lein/Boot version

Lein 2.8.1

Emacs version

24.5

Operating system

Elementary OS Loki based on Ubuntu 16.04

[bbatsov]

Can you, please, post here the message exchange between CIDER and nREPL (as described here http://cider.readthedocs.io/en/latest/troubleshooting/)? This will give us a much better idea about the exact nature of the problem.

[soulawaker]

Sure. You mean *nREPL-messages* buffer?
I paste it below.
The remote REPL server run in docker container in remote machine.
I've tested the Luminus-framework example project, guestbook.

(-->
  id         "14"
  op         "info"
  session    "b046f262-bbe1-4926-bd39-1af0d21260be"
  time-stamp "2018-01-01 19:04:21.099183274"
  ns         "guestbook.db.core"
  symbol     "conman/bind-connection"
)
(<--
  id           "14"
  session      "b046f262-bbe1-4926-bd39-1af0d21260be"
  time-stamp   "2018-01-01 19:04:21.127424709"
  arglists-str "[conn & filenames]"
  column       1
  file         "jar:file:/root/.m2/repository/conman/conman/0.6.2/conman-0.6..."
  line         31
  macro        "true"
  name         "bind-connection"
  ns           "conman.core"
  resource     "conman/core.clj"
  status       ("done")
)

Add another sample

(-->
  id         "22"
  op         "info"
  session    "13085013-a158-41f6-ba4b-1f8ba37c72ac"
  time-stamp "2018-01-01 22:48:11.441079063"
  ns         "guestbook.test.db.core"
  symbol     "mount/start"
)
(<--
  id         "22"
  session    "13085013-a158-41f6-ba4b-1f8ba37c72ac"
  time-stamp "2018-01-01 22:48:11.457146616"
  status     ("done" "no-info")
)

[bbatsov]

The first example seems fine, so IMO this should take you to the source.

The second is odd - seems there's no metadata for mount/start. Is this var evaluated?

Regarding the first example - it'd be nice if you debugged the cider-find-var command as described here https://cider.readthedocs.io/en/latest/troubleshooting/#debugging-cider-commands

I'm pretty puzzled by the fact that you got all the data you needed but the lookup is not working.

[soulawaker]

What I found is that cider-find-file in cider--find-buffer-for-file is not working properly in its place. This happened only in remote machine with Tramp, not local repository.

For example, here is nrepl-messages.

(-->
  id         "30"
  op         "info"
  session    "57dd5648-730e-491a-a815-1cd30a676312"
  time-stamp "2018-01-02 23:52:54.496649712"
  ns         "guestbook.routes.home"
  symbol     "db/save-message!"
)
(<--
  id         "30"
  session    "57dd5648-730e-491a-a815-1cd30a676312"
  time-stamp "2018-01-02 23:52:54.556431954"
  doc        "creates a new message"
  file       "file:/root/guestbook/src/clj/guestbook/db/core.clj"
  name       "save-message!"
  ns         "guestbook.db.core"
  status     ("done")
)

I used the Edebugger to watch steps from cider-find-var.
Then I start jump to definition with the symbol db/save-message!
(Oh, I used Spacemacs based on Emacs 24.5. Sorry for late report if it is related.)
This takes the process to an weird prompt No comment syntax is defined. Use:.
Even it can't be canceled by C-g.

And some other weird things happened in cider-find-file.
I will test more sometimes.

[soulawaker]

In cider-find-file, match-string malfunctions.
It received sane parameters then evaluated it to nil.
According to my watch, all two parts used it do such abnormal behavior.

 (cond ((string-match "^file:\\(.+\\)" url)
         (when-let* ((file (cider--url-to-file (match-string 1 url)))  <---- Here, first!
                     (path (cider--file-path file)))
           (find-file-noselect path)))
        ((string-match "^\\(jar\\|zip\\):\\(file:.+\\)!/\\(.+\\)" url)
         (when-let* ((entry (match-string 3 url))                       <---- And second!
                     (file  (cider--url-to-file (match-string 2 url)))
                     (path  (cider--file-path file))
                     (name  (format "%s:%s" path entry)))

But those parts, not calling cider-find-file defun, are all fine on test in *scratch* buffer. The parameter is the same as my previous comment, "file:/root/guestbook/src/clj/guestbook/db/core.clj".
Why this happen? I can't reason out instantly.

[bbatsov]

So, basically you're saying (match-string 1/3 url) returns nil, right? I can't imagine how this might be happening if the string-match succeeds. The regular expression parentheses seem fine to me.

[soulawaker]

Yes, Edebugger shows that string-match return 0 but match-string return nil. Don't you reproduce it in remote environment?

[soulawaker]

Until yesterday I had tried just edebug-step-mode. Today I've tried edebug-set-breakpoint and edebug-forward-sexp. I thought two method show the same result but not. match-string returned nil with the former. With the latter, it returns normal result. But in the process, an error, "Error running timer `auto-revert-buffers': (wrong-type-argument stringp nil)", is occurred. Then, this takes me finally to an empty buffer which name is what I want.

[soulawaker]

I found and finally fixed it. After more examinations I would like to send PR.

[bbatsov]

@soulawaker Happy to hear this! Looking forward to that PR!