Open Radar

 
Summary:
The problem comes up when using a "mono-spaced-digit" version of the System font, for example in a count-down timer. When that is used in a UITextField which has auto-resizing enabled, then it switches to flexible-width-digits after auto-resizing kicks in.

Steps to Reproduce:
1. Setup a UITextField with auto-resizing enabled and mono-spaced digits. For example:

UITextField *field = [[UITextField alloc] initWithFrame:frame];
field.minimumFontSize = 20;
field.font = [UIFont monospacedDigitSystemFontOfSize:44 weight:UIFontWeightSemibold];
field.adjustsFontSizeToFitWidth = YES;

2. Put some text with digits in the field
3. Resize the field such that the text does not fit anymore with the original font size. 


Expected Results:
The digits to keep an identical width for all digits. 

Actual Results:
The digits switch to dynamic font width, such that a number that is counting will wiggle around because of the varying digit widths. 

Version:
9.2 (13C75)

Notes:
Code tested with XCode Version 7.2 (7C68).
See also http://stackoverflow.com/questions/34594614/auto-resize-a-monospaceddigit-font-in-ios-9

Configuration:
iPhone 6