UILabel is not auto-shrinking text to fit label size

Question

I have this strange issue, and im dealing with it for more than 8 hours now.. Depending on situation i have to calculate UILabels size dynamically,
e.g

Answer 1

Swift 4, Xcode 9.4.1

The solution that worked for me: I had a label within a collection view cell, and the label text was getting trimmed. Set the attributes as below on Storyboard

Lines = 0
LineBreak = Word Wrap
Set yourlabel's leading and trailing constraint = 0 (using Autolayout)