*cider-error* buffer seem to have buffer-undo activated

[Arcanum-XIII]

I have this error quite often :

Warning (undo): Buffer cider-error' undo info was 14111968 bytes long. The undo info was discarded because it exceededundo-outer-limit'.

(Origin of the error seem to be an issue between piggieback/weasel | boot-cljs-repl | cider, filling the cider-error buffer)

I don't think this buffer need the undo to be activated ?

[cichli]

I don't think there should ever be that much data in the error buffer... we should definitely disable undo regardless.

Can you share the versions of cider/cider-nrepl/clojurescript/piggieback/weasel, or (even better) a project that will let me replicate? Or share what happens if you try do what you were trying to do in a normal lein repl?

[Arcanum-XIII]

latest cider from melpa | cider nrepl 9.0-snapshot | piggieback should be 0.16-snapshot and weasel-6.0 (if my understanding of the boot-cljs-repl is correct - meaning I override piggieback/weasel in my local build.boot)
Boot is updated daily with 'boot -u'

I agree that something fishy is going on - especially since most of the time the cider-error buffer is "looking" empty - the joy of clojurescript ?

[noprompt]

I think this happens because it is getting hung up on dumping the exception info which contains the entire ClojureScript compiler analyzer data (this can be enormous).

1. Unhandled clojure.lang.ExceptionInfo
   #<TypeError: Cannot read property 'call' of undefined>
   {:type :js-eval-exception,
    :error
    {:status :exception,
     :value "#<TypeError: Cannot read property 'call' of undefined>",
     :stacktrace
     "TypeError: Cannot read property 'call' of undefined\n    at eval (eval at <anonymous> (file:///Users/noprompt/git/outpace/glimpse-dev/resources/public/js/out/weasel/repl.js:25:470), <anonymous>:8:36)\n    at eval (eval at <anonymous> (file:///Users/noprompt/git/outpace/glimpse-dev/resources/public/js/out/weasel/repl.js:25:470), <anonymous>:22:3)\n    at eval (eval at <anonymous> (file:///Users/noprompt/git/outpace/glimpse-dev/resources/public/js/out/weasel/repl.js:25:470), <anonymous>:30:3)\n    at file:///Users/noprompt/git/outpace/glimpse-dev/resources/public/js/out/weasel/repl.js:25:465\n    at file:///Users/noprompt/git/outpace/glimpse-dev/resources/public/js/out/weasel/repl.js:34:4\n    at cljs.core.MultiFn.call.G__11305__2 (file:///Users/noprompt/git/outpace/glimpse-dev/resources/public/js/out/cljs/core.js:31473:113)\n    at cljs.core.MultiFn.call.G__11305 [as call] (file:///Users/noprompt/git/outpace/glimpse-dev/resources/public/js/out/cljs/core.js:32177:20)\n    at null.<anonymous> (file:///Users/noprompt/git/outpace/glimpse-dev/resources/public/js/out/weasel/repl.js:153:71)\n    at goog.events.EventTarget.fireListeners (file:///Users/noprompt/git/outpace/glimpse-dev/resources/public/js/out/goog/events/eventtarget.js:285:23)\n    at Function.goog.events.EventTarget.dispatchEventInternal_ (file:///Users/noprompt/git/outpace/glimpse-dev/resources/public/js/out/goog/events/eventtarget.js:382:26)"},
    :repl-env
    {:cljs.env/compiler
     #<Atom@638db3d7: 
       {:cljs.compiler/compiled-cljs
...

The total number of lines is 1741812...

[cichli]

@noprompt you're right - cljs.repl/evaluate-form, which piggieback relies upon, used to print a stacktrace and return nil when an exception was thrown. It now throws an ExceptionInfo whose data map includes (amongst other things) the entire CLJS REPL environment (and by extension the analyzer/compiler environment). The middleware pprints this to a string here, which pegs a Java process at 100% until I kill it (I didn't stick around for it to start killing emacs).

A workaround for now is to set cider-stacktrace-print-level to a low number like 5. Adding an equivalent option for setting *print-length* helps a bit but at a depth of 13 you hit what appears to be all of the non-minified Closure library in a single string.

@bbatsov a prudent solution for now is probably to blacklist the :repl-env key. Maybe in the long term we should use the inspector for optional browsing of this data rather than always printing it.

[bbatsov]

@bbatsov a prudent solution for now is probably to blacklist the :repl-env key. Maybe in the long term we should use the inspector for optional browsing of this data rather than always printing it.

Fine by me.