In a certain app state, Array.prototype.filter() returns incorrect results in Safari 8

Originator:ryan
Number:rdar://17186034 Date Originated:05-Jun-2014 03:03 PM
Status:Closed Resolved:Duplicate of 17019752
Product:Safari Product Version:8.0 (10538.35.8)
Classification:Serious Reproducible:Always
 
Summary:
The Router component in the YUI JS library somehow induces a certain state that temporarily causes Array.prototype.filter() to return incorrect results (an empty array instead of a correctly filtered array).

I've been unable to track down the precise cause of this state, but it's at least consistently reproducible using the attached test case, which is also visible at http://jsbin.com/potewaye/13/edit?js,console

The test succeeds in all browsers except Safari 8. I don't think the problem lies with YUI, since YUI's router has been in wide production use for several years and this problem only surfaced in Safari 8.

http://www.smugmug.com/ is one such production website affected by this bug.

Steps to Reproduce:
1. Run the attached test case.

Expected Results:
Three separate arrays should be logged to the console: ["started"], ["finished"], and ["foo"].

Actual Results:
In Safari 8, the logged arrays are ["started"], ["finished"], and [], and you'll see the error message "Array.prototype.filter() failed!" indicating that Array.prototype.filter() returned incorrect results.

Version:
Safari Version 8.0 (10538.35.8)
OS X 10.10 (14A238x)

Notes:


Configuration:
Occurs in Safari 8 on OS X 10.10.

Does not occur in Safari 7 on OS X 10.9, in Google Chrome 35.0.1916.114, or in Firefox 29.0.1.

Attachments:

Comments

Apple closed this as a duplicate of rdar://17019752

By ryan at June 11, 2014, 7:07 p.m. (reply...)

Also filed this at https://bugs.webkit.org/show_bug.cgi?id=133577 since it occurs in WebKit nightlies as well.

By ryan at June 6, 2014, 5:03 p.m. (reply...)

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