on at least some form elements .hide(0) acts as a toggle instead of simply hiding

[randy@…]

If .hide() is applied with duration 0 (I haven't actually tried other values yet), either as a single argument or an object {duration: 0}, to some elements within a form (at least the label & radio buttons will work this way), it acts as a toggle instead of just hiding the element regardless of its former state.

Without arguments, it behaves correctly.

If you switch to jQuery-1.10.2, it behaves as expected.

It seems to (mis)behave the same in Firefox & Chrome. I don't know about IE yet.

​http://jsfiddle.net/KarMannJRO/YTGvH/

Click the "hide it" button repeatedly. The <p> element disappears, and stays hidden; the label & associated input toggle between hidden & shown.

[randy@…]

Also, for a slightly more reduced case, it works similarly if you remove the label element but leave the input, and update the JS .hide() line appropriately, except that then it's only the button itself that toggles, of course, and the text remains shown throughout.

​http://jsfiddle.net/KarMannJRO/YTGvH/3/

[KarMannJRO]

Biggest, less reduced case shows that it affects all type of input elements (except hidden, I suppose) and textareas & labels alike.

​http://jsfiddle.net/KarMannJRO/YTGvH/4/

[KarMannJRO]

Also, I've tried it with other values for duration, and it looks like it doesn't matter what the value is, just that it's specified. Also, the showing is always instant regardless of duration value. Handy test cases here: ​http://jsfiddle.net/KarMannJRO/YTGvH/6/

[Richard Gibson]

Effects: Don't overwrite display:none when .hide()ing hidden elements

Fixes #14848 Closes gh-1548

Changeset: 890d441aa5d319e49951ba6f0ec719cd4cb96759