Swizzlie a process to warn of breaking autolayout.

UIView+BreakedLayout.swift

import UIKit

extension UIView {                                                                                        
                                                                                                          
    /// Swizzlie a process to warn of breaking autolayout.                                                
   static func swizzleBreakedLayoutWarning() {                                                            
        let anyClass: AnyClass = UIView.self                                                              
        let originalSelector = Selector(("engine:willBreakConstraint:dueToMutuallyExclusiveConstraints:"))
        let swizzledSelector = #selector(swizzledEngine(_:willBreak:dueTo:))                              
        guard let originalMethod = class_getInstanceMethod(anyClass, originalSelector),                   
            let swizzledMethod = class_getInstanceMethod(anyClass, swizzledSelector) else { return }      
        method_exchangeImplementations(originalMethod, swizzledMethod)                                    
    }                                                                                                     
                                                                                                          
    /// Swizzled the autolayout engin method.                                                             
    ///                                                                                                   
    /// - Parameters:                                                                                     
    ///   - engine: NSISEngine (Private Class)                                                            
    ///   - constraint: NSLayoutConstraint                                                                
    ///   - mutuallyExclusiveConstraints: [NSLayoutConstraint]                                            
    @objc private func swizzledEngine(                                                                    
        _ engine: Any,                                                                                    
        willBreak constraint: NSLayoutConstraint,                                                         
        dueTo mutuallyExclusiveConstraints: [NSLayoutConstraint]) {                                       
        NSLog("Breaked Constraint: %@", constraint)                                                       
        if let view = constraint.firstItem as? UIView {                                                   
            addWarningLayer(to: view)                                                                     
        }                                                                                                 
        if let view = constraint.secondItem as? UIView {                                                  
            addWarningLayer(to: view)                                                                     
        }                                                                                                 
    }                                                                                                     
                                                                                                          
    /// Adds warning red layer to view's sub layer.                                                       
    ///                                                                                                   
    /// - Parameter view: Warned View                                                                     
    private func addWarningLayer(to view: UIView) {                                                       
        let layer = CALayer()                                                                             
        layer.frame = CGRect(origin: .zero, size: view.frame.size)                                        
        layer.backgroundColor = UIColor.red.withAlphaComponent(0.1).cgColor                               
        view.layer.addSublayer(layer)                                                                     
    }                                                                                                     
}