Added -isEqual: and -hash to MASViewAttribute

@@ -7,6 +7,8 @@
 	objects = {
 
 /* Begin PBXBuildFile section */
+		4490B5BD1805A4AE00C7D494 /* MASViewAttributeSpec.m in Sources */ = {isa = PBXBuildFile; fileRef = 4490B5BB1805A41A00C7D494 /* MASViewAttributeSpec.m */; };
+		4490B5BE1805A4AF00C7D494 /* MASViewAttributeSpec.m in Sources */ = {isa = PBXBuildFile; fileRef = 4490B5BB1805A41A00C7D494 /* MASViewAttributeSpec.m */; };
 		81A5AEFE5B9041ABBC74F614 /* libPods-Masonry Mac Tests.a in Frameworks */ = {isa = PBXBuildFile; fileRef = 8A66D49D177E45D1B8059268 /* libPods-Masonry Mac Tests.a */; };
 		9C61C40117CCF3F0001A124A /* Cocoa.framework in Frameworks */ = {isa = PBXBuildFile; fileRef = 9C61C40017CCF3F0001A124A /* Cocoa.framework */; };
 		9CEFD2D917CCF7210014B0FF /* UIKit.framework in Frameworks */ = {isa = PBXBuildFile; fileRef = 9CEFD2D817CCF7210014B0FF /* UIKit.framework */; };
@@ -102,6 +104,7 @@
 
 /* Begin PBXFileReference section */
 		3FF61518EB0044E0A00EB62E /* libPods-Masonry iOS Tests.a */ = {isa = PBXFileReference; explicitFileType = archive.ar; includeInIndex = 0; path = "libPods-Masonry iOS Tests.a"; sourceTree = BUILT_PRODUCTS_DIR; };
+		4490B5BB1805A41A00C7D494 /* MASViewAttributeSpec.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = MASViewAttributeSpec.m; sourceTree = "<group>"; };
 		8A66D49D177E45D1B8059268 /* libPods-Masonry Mac Tests.a */ = {isa = PBXFileReference; explicitFileType = archive.ar; includeInIndex = 0; path = "libPods-Masonry Mac Tests.a"; sourceTree = BUILT_PRODUCTS_DIR; };
 		9C61C40017CCF3F0001A124A /* Cocoa.framework */ = {isa = PBXFileReference; lastKnownFileType = wrapper.framework; name = Cocoa.framework; path = Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.9.sdk/System/Library/Frameworks/Cocoa.framework; sourceTree = DEVELOPER_DIR; };
 		9CC1B90117CCE7BA0032BB18 /* Masonry-Info.plist */ = {isa = PBXFileReference; lastKnownFileType = text.plist.xml; path = "Masonry-Info.plist"; sourceTree = "<group>"; };
@@ -280,6 +283,7 @@
 				DDF0BE9417C9D6DA00DEA237 /* MASConstraintMakerSpec.m */,
 				DDB682AC17DC484900159454 /* View+MASAdditionsSpec.m */,
 				DDB4A51417DC492F0055EDFE /* NSLayoutConstraint+MASDebugAdditionsSpec.m */,
+				4490B5BB1805A41A00C7D494 /* MASViewAttributeSpec.m */,
 			);
 			name = Specs;
 			sourceTree = "<group>";
@@ -627,6 +631,7 @@
 				DDF0BE9517C9D6DA00DEA237 /* MASConstraintMakerSpec.m in Sources */,
 				DDB682AD17DC484900159454 /* View+MASAdditionsSpec.m in Sources */,
 				DDB4A51517DC492F0055EDFE /* NSLayoutConstraint+MASDebugAdditionsSpec.m in Sources */,
+				4490B5BE1805A4AF00C7D494 /* MASViewAttributeSpec.m in Sources */,
 			);
 			runOnlyForDeploymentPostprocessing = 0;
 		};
@@ -654,6 +659,7 @@
 				DDF0BE9617C9D6DA00DEA237 /* MASConstraintMakerSpec.m in Sources */,
 				DDB682AE17DC484900159454 /* View+MASAdditionsSpec.m in Sources */,
 				DDB4A51617DC492F0055EDFE /* NSLayoutConstraint+MASDebugAdditionsSpec.m in Sources */,
+				4490B5BD1805A4AE00C7D494 /* MASViewAttributeSpec.m in Sources */,
 			);
 			runOnlyForDeploymentPostprocessing = 0;
 		};

@@ -24,4 +24,23 @@
     return self.layoutAttribute == NSLayoutAttributeWidth || self.layoutAttribute == NSLayoutAttributeHeight;
 }
 
+- (BOOL)isEqual:(id)object
+{
+    if ([object isKindOfClass:self.class]) {
+        MASViewAttribute *attr = object;
+        return ([self.view isEqual:attr.view] && self.layoutAttribute == attr.layoutAttribute);
+    }
+    return [super isEqual:object];
+}
+
+// Based on http://www.mikeash.com/pyblog/friday-qa-2010-06-18-implementing-equality-and-hashing.html
+
+#define NSUINT_BIT (CHAR_BIT * sizeof(NSUInteger))
+#define NSUINTROTATE(val, howmuch) ((((NSUInteger)val) << howmuch) | (((NSUInteger)val) >> (NSUINT_BIT - howmuch)))
+
+- (NSUInteger)hash
+{
+    return NSUINTROTATE([self.view hash], NSUINT_BIT / 2) ^ self.layoutAttribute;
+}
+
 @end

+//
+//  MASViewAttributeSpec.m
+//  Masonry
+//
+//  Created by Craig Siemens on 2013-10-09.
+//  Copyright 2013 Jonas Budelmann. All rights reserved.
+//
+
+#import "MASViewAttribute.h"
+
+SpecBegin(MASViewAttributeSpec)
+
+__block UIView *view;
+__block MASViewAttribute *viewAttribute;
+
+beforeEach(^{
+    view = [UIView new];
+    viewAttribute = [[MASViewAttribute alloc] initWithView:view layoutAttribute:NSLayoutAttributeLeft];
+});
+
+context(@"isEqual", ^{
+    
+    it(@"should return YES whe the view and layoutAttribute are the same", ^{
+        MASViewAttribute *otherViewAttribute = [[MASViewAttribute alloc] initWithView:viewAttribute.view
+                                                                      layoutAttribute:viewAttribute.layoutAttribute];
+        expect([viewAttribute isEqual:otherViewAttribute]).to.equal(YES);
+    });
+    
+    it(@"should return NO when the view is different but the layoutAttribute is the same", ^{
+        UIView *otherView = [UIView new];
+        MASViewAttribute *otherViewAttribute = [[MASViewAttribute alloc] initWithView:otherView
+                                                                      layoutAttribute:viewAttribute.layoutAttribute];
+        expect([viewAttribute isEqual:otherViewAttribute]).to.equal(NO);
+    });
+    
+    it(@"should return NO when the view is the same but the layoutAttribute is different", ^{
+        MASViewAttribute *otherViewAttribute = [[MASViewAttribute alloc] initWithView:viewAttribute.view
+                                                                      layoutAttribute:NSLayoutAttributeRight];
+        expect([viewAttribute isEqual:otherViewAttribute]).to.equal(NO);
+    });
+
+    it(@"should return NO when the view is different and the layoutAttribute is different", ^{
+        UIView *otherView = [UIView new];
+        MASViewAttribute *otherViewAttribute = [[MASViewAttribute alloc] initWithView:otherView
+                                                                      layoutAttribute:NSLayoutAttributeRight];
+        expect([viewAttribute isEqual:otherViewAttribute]).to.equal(NO);
+    });
+});
+
+context(@"hash", ^{
+    
+    it(@"should return the same hash when the view and layoutAttribute are the same", ^{
+        MASViewAttribute *otherViewAttribute = [[MASViewAttribute alloc] initWithView:viewAttribute.view
+                                                                      layoutAttribute:viewAttribute.layoutAttribute];
+        expect([viewAttribute hash]).to.equal([otherViewAttribute hash]);
+    });
+    
+    it(@"should return a different hash when the view is different but the layoutAttribute is the same", ^{
+        UIView *otherView = [UIView new];
+        MASViewAttribute *otherViewAttribute = [[MASViewAttribute alloc] initWithView:otherView
+                                                                      layoutAttribute:viewAttribute.layoutAttribute];
+        expect([viewAttribute hash]).toNot.equal([otherViewAttribute hash]);
+    });
+    
+    it(@"should return a different hash when the view is the same but the layoutAttribute is different", ^{
+        MASViewAttribute *otherViewAttribute = [[MASViewAttribute alloc] initWithView:viewAttribute.view
+                                                                      layoutAttribute:NSLayoutAttributeRight];
+        expect([viewAttribute hash]).toNot.equal([otherViewAttribute hash]);
+    });
+    
+    it(@"should return a different hash when the view is different and the layoutAttribute is different", ^{
+        UIView *otherView = [UIView new];
+        MASViewAttribute *otherViewAttribute = [[MASViewAttribute alloc] initWithView:otherView
+                                                                      layoutAttribute:NSLayoutAttributeRight];
+        expect([viewAttribute hash]).toNot.equal([otherViewAttribute hash]);
+    });
+});
+
+SpecEnd