I just bought Paul Hudson's Testing Swift, I hope that it keeps me writing TEST FIRST as I just finished a great 3 day course with James Grenning on Embedded C TDD.
https://www.hackingwithswift.com/store/testing-swift
James did a wonderful job of explaining how he codes and why he uses the TDD methods to make robust software. There was no, hard pitch - you have to do it this way or you're doomed... NONE of that. Just a very experienced master with insights and compassion for the new-kids coming along.
I would highly recommend you taking one of James' courses at Windman Software (and the P-38 logo is cool).
Here's a free sample of James' book I've not read it... I don't do embedded programming... that's the hard stuff.
This is a great book - I've got the ePub on my Mac and it has a great visual experience for the learner... along with code to try your self.
I highly recommend this book - SwiftUI Views Mastery