Layout constraint extensions for UIView

LayoutConstrainable.swift

import UIKit

protocol LayoutConstrainable {
    @discardableResult func height(_ height: CGFloat, priority: UILayoutPriority) -> Self
    @discardableResult func width(_ width: CGFloat, priority: UILayoutPriority) -> Self
    @discardableResult func size(_ size: CGSize, priority: UILayoutPriority) -> Self
    @discardableResult func top(to: Self, constant: CGFloat, priority: UILayoutPriority) -> Self
    @discardableResult func leading(to: Self, constant: CGFloat, priority: UILayoutPriority) -> Self
    @discardableResult func trailing(to: Self, constant: CGFloat, priority: UILayoutPriority) -> Self
    @discardableResult func bottom(to: Self, constant: CGFloat, priority: UILayoutPriority) -> Self
    @discardableResult func snap(to: Self, insets: UIEdgeInsets, priority: UILayoutPriority) -> Self
}

extension UIView: LayoutConstrainable {

    @discardableResult func height(_ height: CGFloat, priority: UILayoutPriority = .required) -> Self {
        translatesAutoresizingMaskIntoConstraints = false
        heightAnchor.constraint(equalToConstant: height).isActive = true
        return self
    }

    @discardableResult func width(_ width: CGFloat, priority: UILayoutPriority = .required) -> Self {
        translatesAutoresizingMaskIntoConstraints = false
        widthAnchor.constraint(equalToConstant: width).isActive = true
        return self
    }

    @discardableResult func size(_ size: CGSize, priority: UILayoutPriority = .required) -> Self {
        translatesAutoresizingMaskIntoConstraints = false
        widthAnchor.constraint(equalToConstant: size.width).isActive = true
        heightAnchor.constraint(equalToConstant: size.height).isActive = true
        return self
    }

    @discardableResult func top(to: UIView, constant: CGFloat = 0, priority: UILayoutPriority = .required) -> Self {
        translatesAutoresizingMaskIntoConstraints = false
        to.translatesAutoresizingMaskIntoConstraints = false
        topAnchor.constraint(equalTo: to.topAnchor, constant: constant).isActive = true
        return self
    }

    @discardableResult func leading(to: UIView, constant: CGFloat = 0, priority: UILayoutPriority = .required) -> Self {
        translatesAutoresizingMaskIntoConstraints = false
        to.translatesAutoresizingMaskIntoConstraints = false
        leadingAnchor.constraint(equalTo: to.leadingAnchor, constant: constant).isActive = true
        return self
    }

    @discardableResult func trailing(to: UIView, constant: CGFloat = 0, priority: UILayoutPriority = .required) -> Self {
        translatesAutoresizingMaskIntoConstraints = false
        to.translatesAutoresizingMaskIntoConstraints = false
        trailingAnchor.constraint(equalTo: to.trailingAnchor, constant: constant).isActive = true
        return self
    }

    @discardableResult func bottom(to: UIView, constant: CGFloat = 0, priority: UILayoutPriority = .required) -> Self {
        translatesAutoresizingMaskIntoConstraints = false
        to.translatesAutoresizingMaskIntoConstraints = false
        bottomAnchor.constraint(equalTo: to.bottomAnchor, constant: constant).isActive = true
        return self
    }

    @discardableResult func snap(to: UIView, insets: UIEdgeInsets = .zero, priority: UILayoutPriority = .required) -> Self {
        translatesAutoresizingMaskIntoConstraints = false
        to.translatesAutoresizingMaskIntoConstraints = false
        topAnchor.constraint(equalTo: to.topAnchor, constant: insets.top).isActive = true
        leadingAnchor.constraint(equalTo: to.leadingAnchor, constant: insets.left).isActive = true
        bottomAnchor.constraint(equalTo: to.bottomAnchor, constant: -insets.bottom).isActive = true
        trailingAnchor.constraint(equalTo: to.trailingAnchor, constant: -insets.right).isActive = true
        return self
    }
}