From fc3ad86b6b9a5e90072e27398231d07c20c886fb Mon Sep 17 00:00:00 2001
From: Dieter Baron <dillo@nih.at>
Date: Thu, 26 May 2016 01:04:11 +0200
Subject: [PATCH] Avoid duplicating keys in will/did method calls.

Add accessingValueForKey() that takes a key and a block and wraps the block in willAccessValueForKey()/didAccessValueForKey(); same for will/didChangeValueForKey.

This allows writing:

var foo {
    return accessingValueForKey(Keys.Foo) { primitiveFoo }
}
---
 SharedCode/KeyCodable.swift | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/SharedCode/KeyCodable.swift b/SharedCode/KeyCodable.swift
index 511afd8..3bbff62 100644
--- a/SharedCode/KeyCodable.swift
+++ b/SharedCode/KeyCodable.swift
@@ -22,6 +22,12 @@ extension KeyCodable where Self: ManagedObject, Keys.RawValue == String {
         didAccessValueForKey(key.rawValue)
     }
 
+    public func accessingValueForKey(key: Keys, @noescape block: () -> ()) {
+        willAccessValueForKey(key)
+        block()
+        didAccessValueForKey(key)
+    }
+
     public func willChangeValueForKey(key: Keys) {
         (self as ManagedObject).willChangeValueForKey(key.rawValue)
     }
@@ -42,6 +48,12 @@ extension KeyCodable where Self: ManagedObject, Keys.RawValue == String {
         return changedValues()[key.rawValue]
     }
 
+    public func changingValueForKey(key: Keys, @noescape block: () -> ()) {
+        willChangeValueForKey(key)
+        block()
+        didChangeValueForKey(key)
+    }
+
     public func committedValueForKey(key: Keys) -> AnyObject? {
         return committedValuesForKeys([key.rawValue])[key.rawValue]
     }