Printing in lazy-evaluated code sends output to babashka process instead of the nrepl client

[llacom]

It seems I stumbled upon a bug: when using babashka as an nrepl server, printing something will correctly send the output to the nrepl client, however printing something inside something lazy-evaluated will instead send the result to babashka process itself:

user=> (mapv (fn [x] (println "It works" x) (inc x)) [10 20])
It works 10
It works 20
[11 21]
user=> (map (fn [x] (println "It prints in babashka process" x) (inc x)) [10 20])
(11 21)

Tested with

`--> bb --version
babashka v0.2.10

[borkdude]

@bbatsov Could you point me to how this is handled in nrepl/nrepl? Do you change the root binding of *out*, or do you force lazy sequences before sending?

[bbatsov]

I think the relevant code starts here https://github.com/nrepl/nrepl/blob/master/src/clojure/nrepl/middleware/interruptible_eval.clj#L81 There's no special handling for lazy sequences, but we do rebind the output streams in the evaluation logic.

[bbatsov]

I think the relevant code starts here https://github.com/nrepl/nrepl/blob/master/src/clojure/nrepl/middleware/interruptible_eval.clj#L81 There's no special handling for lazy sequences, but we do rebind the output streams in the evaluation logic.

[borkdude]

Fixed.