`defaultDisplay()` may return inaccurate results

[mathias]

​https://github.com/jquery/jquery/blob/c0450f3c2aab7af902ccf4ba0537088fc26f065d/src/effects.js#L582

The new defaultDisplay() only uses the iframe when display === "none" or display === "".

A simple CSS rule like div { display: inline; } or div { display: inline-block; }will cause defaultDisplay('div') to return 'inline'.

It would probably be safer to always use the iframe technique.

[timmywil]

Hmm, even though that is not the real default display, isn't that the desired behavior? Considering the user wants all divs to be display: inline, shouldn't we set to display: inline when showing?

[Rick Waldron]

Just to clarify, the defaultDisplay() commits that I made were actually to address this very issue and to "force" the desired behaviour.

I'm going to bounce this back to @mathias - can you provide a reduced test case that shows the behaviour you describe above?

[mathias]

timmywil: Good point. But then I don’t think it should be named defaultDisplay but rather desiredDisplay or something like that.

[Rick Waldron]

@timmywil & @mathias

the code that creates an iframe, etc will only run when show() or hide() come up with the wrong display state for an element, which will only happen when the user does something absurd like: span { display: none; }

[Rick Waldron]

Also, this is awesome... someone has kindly provided us with a real case:

​http://bugs.jquery.com/ticket/9106

See, they REALLY do that :(

[mathias]

Feel free to close this bug as invalid, since defaultDisplay() actually works as intended (minor bugs like #8994 aside). At most, I would vouch to rename it to desiredDisplay() for clarity. Just say the word if you agree and I’ll add another commit to my pull request for #8994.