ace editor causing errors

[matt]

i have recently come across these error messages ocurring together in sequence

copied from chrome console

ace.js:10276 Uncaught TypeError: Cannot read property 'row' of undefined

    at EditSession.$computeWidth (ace.js:10276)

    at EditSession.getScreenWidth (ace.js:10248)

    at VirtualRenderer.$getLongestLine (ace.js:17864)

    at VirtualRenderer.$computeLayerConfig (ace.js:17758)

    at VirtualRenderer.$renderChanges (ace.js:17639)

    at VirtualRenderer.onResize (ace.js:17319)

    at Array.<anonymous> (ace.js:17139)

    at Text.EventEmitter._signal (ace.js:4162)

    at Text.<anonymous> (ace.js:15661)

    at exports.FontMetrics.EventEmitter._emit.EventEmitter._dispatchEvent (ace.js:4146)

ace.js:15265 Uncaught TypeError: Cannot read property 'className' of undefined

    at Gutter.update (ace.js:15265)

    at VirtualRenderer.$renderChanges (ace.js:17664)

    at VirtualRenderer.onResize (ace.js:17319)

    at Array.<anonymous> (ace.js:17139)

    at Text.EventEmitter._signal (ace.js:4162)

    at Text.<anonymous> (ace.js:15661)

    at exports.FontMetrics.EventEmitter._emit.EventEmitter._dispatchEvent (ace.js:4146)

    at exports.FontMetrics.checkForSizeChanges (ace.js:16605)

    at ResizeObserver.<anonymous> (ace.js:16613)

ace.js:9851 Uncaught TypeError: Cannot read property 'length' of undefined

    at EditSession.getTokenAt (ace.js:9851)

    at new TokenIterator (ace.js:6688)

    at ace.js:13174

ace.js:15265 Uncaught TypeError: Cannot read property 'className' of undefined

    at Gutter.update (ace.js:15265)

    at VirtualRenderer.$renderChanges (ace.js:17664)

    at ace.js:16526

ace.js:15265 Uncaught TypeError: Cannot read property 'className' of undefined

    at Gutter.update (ace.js:15265)

    at VirtualRenderer.$renderChanges (ace.js:17697)

    at ace.js:16526

i am using only ace.js from src-noconflict, i just downladed the latest version from github today

i seem to recall having similar issues surrounding this error in the past, it seems to be caused by my code somehow,

previously i found an error in my code and it solved the issue, im bug hunting this one now, but im wondering how

my code is able to affect the editor in this way

thanks,matt

[Harutyun Amirjanyan]

I don't know what could cause this kind of error.

Could you share the relevant part of your code or create a simple page reproducing the error?

​

[matt]

hi harutyun,

i have found the offending line and created a codepen illustrating the error, it boils down to this erroneous piece of code :

          Array.prototype.unshift(arguments,'arbitrary string');

the line in my program was in a statement for debugging and was designed to prepend the module name before calling debugfn.apply(null,arguments) like this

function debug(){

   Array.prototype.unshift(arguments,'modulename');

  debugfn.apply(null,arguments);

}

ok i was writing this very quickly just to explain why i was using this rough construct :-o, the line "should" read Array.prototype.unshift.CALL(arguments,'modulename') should one so wish

anyways the codepen url demonstrating all this as succinctly as i can is :

https://codepen.io/anon/pen/YeoZML?editors=1000

it errs in chrome,firefox and edge

ace is a wonderful editor, thankyou harutyun for all your hardwork

matt