Sizzle cache collision in browsers without querySelectorAll

[jryans]

In browsers without querySelectorAll (IE 6, IE 7, FF 3.0), Sizzle marks the elements it encounters as seen for a particular selection run. The value used as a marker is an integer that comes from an internal counter which is incremented before each new selection, and these markers on left on the elements after selection completes.

This causes trouble when there are two copies of Sizzle on the page. Running a selection in Sizzle copy A sets the marker on a set of elements to 0. If you then run a selection in Sizzle copy B that passes through the same elements, Sizzle will assume it is safe to use a cached value at that point, since the stored marker of 0 matches copy B's marker for this run. This gives unexpected selection results.

See  http://jsfiddle.net/uz4dt/6/ for a test case. The second test fails for browsers without querySelectorAll.

[jryans]

 https://github.com/jeresig/sizzle/pull/53

[rwaldron]

Updating:  https://github.com/jquery/sizzle/pull/53

(not reviewed)

[john]

Nominating ticket for 1.7 discussion.

[rwaldron]

+1, Seems like a bug, should be fixed

[jaubourg]

+1, Sizzle should have a mean to specify which counter field name to use, right?

[timmywil]

+1,

[dmethvin]

+1, although it would be preferable to ban IE6/7 from the planet.

[john]

+1, Not 100% keen on the currently proposed solution but yeah, seems like we can do something here.

[scott.gonzalez]

+1

[addyosmani]

+1

[ajpiano]

+1

[timmywil]

 http://jsfiddle.net/timmywil/uz4dt/16/show/

The property on the element is just elem.sizcache. I'm thinking that should be like jQuery's expando, e.g. sizzle340987234098230. Then done can stay a regular counter and we avoid collisions.

[timmywil]

oh, that's still linking to my local jquery. That can be changed to another jquery location if you'd like to see it working.

[timmywil]

Update sizzle; Add sizzle cache collision iframe test. Fixes #8539.

Changeset: 8723f3b9e1db5d4fdcd50624441fe3536d1ae2f2