nREPL server: missing namespace prompt in CIDER

[ikappaki]

Issue Description

When connecting to the jank nREPL server from CIDER, the REPL buffer does not display the usual ns prompt user>. Input can still be sent, and evaluation works, but the user never sees a prompt indicating readiness for input.

This is caused by CIDER not handling nREPL messages that include both :value and :status keys in the same response, see clojure-emacs/cider#3869.

A PR will follow. The workaround is straightforward (just don't pack value and status on the same response), but since there are currently no nREPL tests, I am first adding some tests leading to this fix, which may take some time to commit.

Reproduction Steps

1. Start the jank REPL:

   jank repl

   Output should indicate the nREPL server is running on a port, e.g.:

   jank nREPL server is running on nrepl://127.0.0.1:45517
   

2. In Emacs:

   • Open a scratch buffer and switch to clojure-mode.

   • Connect to the running jank nREPL server:

     M-x cider-connect-clj
     

     Enter host localhost and the port shown in step 1.

3. Observe the REPL buffer:

   • The buffer opens but no prompt (user>) is shown initially.
   • Typing 5 and pressing Enter will print 5 but still does not show the prompt.
   • The prompt only appears after pressing Enter again.

jank health check

─ system ───────────────────────────────────────────────────────────────────────
─ ✅ operating system: linux
─ ✅ default triple: x86_64-unknown-linux-gnu

─ jank install ─────────────────────────────────────────────────────────────────
─ ✅ jank version: jank-0.1-alpha
─ ✅ jank resource dir: ../lib/jank/0.1 
─ ✅ jank resolved resource dir: /usr/local/bin/../lib/jank/0.1 (found)
─ ✅ jank user cache dir: /home/chaos/.cache/jank/x86_64-unknown-linux-gnu-3f3f53385c890ae1047dabebf6a51d50696c54bc3f3672891e0b3c861b84a2fd (found)

Stack trace

No response

OS Version Information

Ubuntu 24.4, MS-Windows 11

I acknowledge that:

• I have searched the jank repository (both open and closed Discussions and Issues) and confirm this is not a duplicate of an existing issue or discussion.
• I have checked the "Preview" tab on all text fields to ensure that everything looks right, and have wrapped all configuration and code in code blocks with a group of three backticks (```) on separate lines.

[jeaye]

Thank you for the report!

A PR will follow. The workaround is straightforward (just don't pack value and status on the same response), but since there are currently no nREPL tests, I am first adding some tests leading to this fix, which may take some time to commit.

I am very interested in a strong test suite for the REPL server. However, I didn't tackle this yet because I would prefer to unify Clojure's nREPL server test suites in the same way that we're building https://github.com/jank-lang/clojure-test-suite. I have started the discussion here: https://clojurians.slack.com/archives/C17JYSA3H/p1771274659778899

Rather than building some tests specific to jank's nREPL server, I think we're better off taking this time to unify. If that means jank goes without tests for its nREPL server for longer, that's acceptable to me. We've done the same with the clojure-test-suite.

[ikappaki]

Hi @jeaye, I agree that building a general nREPL test suite is a strong direction and could benefit the ecosystem much like the clojure-test-suite.

That said, I still see value in unit testing the individual functions that make up the jank nREPL server, as a complement to protocol level testing and to support development more directly.

While fixing the issue above (only a couple of lines), I added some scaffolding tests (unit level rather than nREPL protocol tests) and addressed a couple of related issues that surfaced in the process: handling partial message reads and supporting negative numbers in the bencode parser.

I’ll open a PR soon with these changes and the tests included. Feel free to keep or discard the unit tests as you see fit.

Thanks

[ikappaki]

#743

[ikappaki]

Fixed with #743