From 29e4bcffabf6d3de06d57cda4dc229dbcc1e45d7 Mon Sep 17 00:00:00 2001
From: "blehner@10.100.20.62" <blehner@regencybeauty.com>
Date: Fri, 17 Oct 2014 10:41:53 -0500
Subject: [PATCH] Added the 'sum' operation to the NSArray method extensions
 and unit tests.

---
 .../LinqToObjectiveCTestTests/NSArrayLinqExtensionsTest.m | 8 ++++++++
 NSArray+LinqExtensions.h                                  | 6 ++++++
 NSArray+LinqExtensions.m                                  | 4 ++++
 3 files changed, 18 insertions(+)

diff --git a/LinqToObjectiveCTest/LinqToObjectiveCTestTests/NSArrayLinqExtensionsTest.m b/LinqToObjectiveCTest/LinqToObjectiveCTestTests/NSArrayLinqExtensionsTest.m
index 4c008f5..c25a0ce 100755
--- a/LinqToObjectiveCTest/LinqToObjectiveCTestTests/NSArrayLinqExtensionsTest.m
+++ b/LinqToObjectiveCTest/LinqToObjectiveCTestTests/NSArrayLinqExtensionsTest.m
@@ -478,4 +478,12 @@ - (void) testReverse
     STAssertEqualObjects(result[1], @25, nil);
 }
 
+- (void) testSum
+{
+    NSArray* input = @[@25, @35];
+    
+    NSNumber* sum = [input linq_sum];
+    STAssertEqualObjects(sum, @60, nil);
+}
+
 @end
diff --git a/NSArray+LinqExtensions.h b/NSArray+LinqExtensions.h
index 8d51020..10478ba 100644
--- a/NSArray+LinqExtensions.h
+++ b/NSArray+LinqExtensions.h
@@ -194,4 +194,10 @@ typedef id (^LINQAccumulator)(id item, id aggregate);
  */
 - (NSArray*) linq_reverse;
 
+/** Sums the elements in the array.
+ 
+ @return The sum of elements within this array.
+ */
+- (NSNumber*)linq_sum;
+
 @end
diff --git a/NSArray+LinqExtensions.m b/NSArray+LinqExtensions.m
index ceba6b8..9801d8d 100644
--- a/NSArray+LinqExtensions.m
+++ b/NSArray+LinqExtensions.m
@@ -237,5 +237,9 @@ - (NSArray *)linq_reverse
     return result;
 }
 
+- (NSNumber *)linq_sum
+{
+    return [self valueForKeyPath: @"@sum.self"];
+}
 
 @end