fix: crash of over-released when using Weak

Author: vnixx

Example/iOS_Example/iOS_Example/KeyboardManagerDemoViewController.swift

@@ -13,6 +13,7 @@ class KeyboardManagerDemoViewController: UIViewController {
 
     deinit {
         print(#function)
+        KeyboardManager.shared.removeObserver(self)
     }
 
     var defaultFrame: CGRect = .zero

Sources/ReerKit/Utility/Weak/Weak.swift

@@ -23,10 +23,18 @@
 public final class Weak<T: AnyObject> {
     public private(set) weak var object: T?
     private let hashKey: Int
+    
     public init(_ object: T) {
         self.object = object
         self.hashKey = ObjectIdentifier(object).hashValue
     }
+    
+    /// Creates a lookup-only instance that can be used for set operations
+    /// without storing a weak reference. Useful when the object may be deallocating.
+    public init(hashKeyOnly object: T) {
+        self.object = nil
+        self.hashKey = ObjectIdentifier(object).hashValue
+    }
 }
 
 extension Weak: Equatable, Hashable {

Sources/ReerKit/Utility/Weak/WeakSet.swift

@@ -53,7 +53,7 @@ public class WeakSet<T: AnyObject>: ExpressibleByArrayLiteral {
     }
 
     public func contains(_ object: T) -> Bool {
-        return objectSet.contains(Weak(object))
+        return objectSet.contains(Weak(hashKeyOnly: object))
     }
 
     public func add(_ object: T) {
@@ -74,11 +74,11 @@ public class WeakSet<T: AnyObject>: ExpressibleByArrayLiteral {
     }
 
     public func remove(_ object: T) {
-        objectSet.remove(Weak(object))
+        objectSet.remove(Weak(hashKeyOnly: object))
     }
 
     public func removeObjects(_ objects: [T]) {
-        objectSet.subtract(objects.map { Weak($0) })
+        objectSet.subtract(objects.map { Weak(hashKeyOnly: $0) })
     }
 
     public func removeAll() {