Cannot read property 'length' of undefined

[MorelSerge]

I'm stumbling on an error: Cannot read property 'length' of undefined

It occurs at dist/muuri.module.js in _updateDragDirection at line 2241:21, meaning right here:

muuri/src/AutoScroller/AutoScroller.js

Line 649 in ebe6eb0

if (dragPositions.length) {

Any help is appreciated!

[niklasramo]

Hi @Vluf ! Can you give specific steps how to reproduce this error? A reduced test case would be nice.

[MorelSerge]

Hi @niklasramo, thanks for getting back to me!
Unfortunately I cannot reproduce this error, it is merely happening in our production SPA and only on Android mobile.

This issue happens during dragging tiles. We happen to log the dragging, so right before crashing it's still logging the drag events.
E.g.

[{"clientX":269,"clientY":496.6666870117187,"screenX":322.3333435058594,"isFirst":false,"distance":0,"deltaX":0,"deltaY":0,"isFinal":false,"deltaTime":0,"srcEvent":"[object TouchEvent]","pageX":322.3333435058594,"pageY":340,"pointerType":"touch","screenY":421,"identifier":0,"type":"move","target":"[object HTMLDivElement]"}]

I'm more than happy to investigate further or deploy some logging for this, but as of right now I cannot reproduce.

Any guidance in how to proceed from here?
Thanks!

[niklasramo]

@Vluf I think I fixed this in the latest version v0.9.2, let me know if you still encounter this issue with that version.

[MorelSerge]

@niklasramo According to Sentry, this is indeed fixed in v0.9.2. Thanks!