From c1adfa327d5a35d696e91c210caa98265f835a58 Mon Sep 17 00:00:00 2001
From: Lily Vulcano <millenomi@apple.com>
Date: Thu, 14 Feb 2019 17:15:40 -0800
Subject: [PATCH] Add additional shims for Operation that mimic the KeyPath<>
 KVC methods.

---
 Foundation/Operation.swift | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/Foundation/Operation.swift b/Foundation/Operation.swift
index a393ef59a3..7147a08642 100644
--- a/Foundation/Operation.swift
+++ b/Foundation/Operation.swift
@@ -186,6 +186,16 @@ extension Operation {
             finish()
         }
     }
+    
+    public func willChangeValue<Value>(for keyPath: KeyPath<Operation, Value>) {
+        // do nothing
+    }
+    
+    public func didChangeValue<Value>(for keyPath: KeyPath<Operation, Value>) {
+        if keyPath == \Operation.isFinished {
+            finish()
+        }
+    }
 }
 
 extension Operation {