[NREPL-20] Stray "#" in session-out is breaking (.println out)

Sat, 9 Jun 2012 10:54:01 -0500

There's a stray "#" in clojure.tools.nrepl.middleware.session/session-out which is turning the body of the (not off) case into a lambda that's never executed:

(cond
(number? x) (.append buf (char x))
(not off) #(.append buf x) ; <----
(instance? CharSequence x) (.append buf ^CharSequence x off len)
:else (.append buf ^chars x off len))

https://github.com/clojure/tools.nrepl/blob/master/src/main/clojure/clojure/tools/nrepl/middleware/session.clj#L34

This is causing the newline character in (.println out) and (.println err) to be lost:

user=> (with-open [conn (repl/connect :port 7888)]
(-> (repl/client conn 1000)
(repl/message {:op :eval :code "(do (.println out \"1\") (.println out \"2\") (.println out \"3\")(flush))"})
doall
pprint))
({:out "123", ;; <--- where are my "\n"s?
...}, ...)

Removing the stray "#" fixes the problem:

{:out "1\n2\n3\n",
...}

Reported downstream by jaceklaskowski in https://github.com/technomancy/leiningen/issues/631

Patch with the trivial fix and unit test here: https://wok.meshy.org/~ato/0001-Remove-stray-hash-in-session-out-that-breaks-println-out.patch

Couldn't attach the patch to this issue as JIRA told me I don't have permission. I (Alex Osborne) have signed the Clojure CA and contribute this patch as per the terms of it.

Clojure JIRA

[NREPL-20] Stray "#" in session-out is breaking (.println *out*)

[NREPL-20] Stray "#" in session-out is breaking (.println out)