1068430 - window.scroll to a number outside the signed 32-bit integer range has odd behavior

Status: UNCONFIRMED

(Core :: DOM: Core & HTML, defect, P5)

Description

[7cc]

User Agent: Mozilla/5.0 (Windows NT 6.0; rv:32.0) Gecko/20100101 Firefox/32.0
Build ID: 20140911151253

Steps to reproduce:

1. scroll to the bottom of a page
2. run window.scroll, 
   passing the second argument a number greater than (Math.pow(2, 31) - window.scrollMaxY + window.pageYOffset)

window.scroll(0, 2147483648 - window.scrollMaxY + window.pageYOffset)


Actual results:

It acts as if window.scroll(0, 0)


Expected results:

no scroll

Comment 1

[7cc]

window.scroll(2147483648 - window.scrollMaxX + window.pageXOffset, 0) behaves the same.

Comment 2

[Boris Zbarsky [:bzbarsky]]

This has nothing to do with pageYOffset.

What's going on is you're calling:

  window.scroll(0, 2147483648)

and internally the arguments to window.scroll are coerced to a 32-bit integer.  The result of this coercion is a negative number.

Comment 3

[7cc]

This has to do with pageYOffset.

the code window.scroll(0, 2147483648 - window.scrollMaxY + window.pageYOffset)
- not at the bottom, scroll down
- only at the bottom, scroll up to the top

whereas window.scroll(0, 2147483648)
- always scroll up to the top

Anyway, yes, it is about a 32-bit integer.

Comment 4

[7cc]

ah... sorry, at first I tested scrollBy.

scrollBy(0, 2147483648 - window.scrollMaxY)

I now realized `scrollBy` calls `scroll` internally. plz ignore the comment 3. thanks.

Comment 5

[Firefox Bug Husbandry Bot]

https://bugzilla.mozilla.org/show_bug.cgi?id=1472046

Move all DOM bugs that haven’t been updated in more than 3 years and has no one currently assigned to P5.

If you have questions, please contact :mdaly.