Open Radar

 
Summary:
When using a UILabel and sizeToFit(), the size returned appears incorrect for certain of the ‘new’ emoji. Specifically those emoji which use U+2764 HEAVY BLACK HEART return the size that would be expected if each emoji were rendered independently.

And actually it seems like in some scenarios they _are_ being rendered independently, although this issue remains even when they are not.

Steps to Reproduce:
insert the appropriate text into a UILabel and call sizeToFit().

Expected Results:
The size should be less then that of the joined emoji, unjoined.

Actual Results:
The size is roughly (n)x wider then expected, where n is the number of emoji in the joined group

Regression:
Describe circumstances where the problem occurs or does not occur, such as software versions and/or hardware configurations.

Notes:
Additionally, I would be _very_ curious about the following:
1) why it was decided to use two distinct joiners for the ’kiss on lips’ combos (👨‍❤️‍💋‍👨), (👨❤️💋👨) when it feels like the 💋
U+1F48B KISS MARK itself contains the semantic information required. 
2) why it was decided to use a heart which requires an emoji variation selector, which feels like basically just asking for trouble, and which probably has _something_ to do with this bug report (I might’ve gone with 💗 U+1F497 GROWING HEART, which has a certain poetry?) 

Anyway, deeply saddened not to have been in the room for this particular bike shed. 😢💭🚴🏠


I’ve included two screenshots: these are from a custom keyboard extension that reads the text before the cursor and then just displays the unicode scalars; it also displays the result of assigning the text and calling sizeToFit() on an otherwise unconfigured uilabel.