cider-pprint-eval-last-sexp doesn't play nicely with infinite sequences

[johnwalker]

; CIDER 0.5.0alpha (Clojure 1.5.1, nREPL 0.2.3)

First, do something that won't terminate:

(interpose (repeat #{}) (list 1 2))

Evaluate the expression with cider-eval-last-sexp (C-x C-e). Wait a few seconds, and abort with cider-interrupt (C-c C-b). Emacs will not crash.

On the other hand, if you use cider-pprint-eval-last-sexp (C-c C-p), the cider-result buffer will start filling with evaluation results. Cider-interrupt appears to halt evaluation, but doesn't prevent cider-eval-last-sexp from printing. Finally, killing the cider-result buffer will prevent Emacs from crashing, but cider-pprint-eval-last-sexp will no longer print future evaluations to cider-result.

[bbatsov]

Hmm, that's nasty. Not sure what the best way to handle this would be. After all - printing infinite sequences is bound to be problematic. let binding print-length seems like the best idea to me, but that'll look kind of ugly in the Emacs Lisp code. A pretty printing middleware seems like a good alternative.

[johnwalker]

Wow thanks!