remove ability to chain equality, less ambiguous if you need to reference constr…

…aint for animation or updating later on

@@ -158,12 +158,8 @@
             [self.delegate addConstraint:self];
             self.added = YES;
         }
-        for (id<MASConstraint> constraint in self.currentChildConstraints.copy) {
-            id<MASConstraint> newConstraint = block(constraint, attr);
-            if (newConstraint != constraint) {
-                [self.currentChildConstraints removeObject:constraint];
-                [self.currentChildConstraints addObject:newConstraint];
-            }
+        for (id<MASConstraint> constraint in self.currentChildConstraints) {
+            block(constraint, attr);
         }
         return self;
     };
@@ -199,7 +195,6 @@
     for (id<MASConstraint> constraint in self.completedChildConstraints) {
         [constraint commit];
     }
-    [self.currentChildConstraints removeAllObjects];
     [self.completedChildConstraints removeAllObjects];
 }
 

@@ -63,18 +63,6 @@
     }
 }
 
-- (instancetype)cloneIfNeeded {
-    if (self.hasLayoutRelation) {
-        MASViewAttribute *firstViewAttribute = [[MASViewAttribute alloc] initWithView:self.firstViewAttribute.view layoutAttribute:self.firstViewAttribute.layoutAttribute];
-        
-        MASViewConstraint *viewConstraint = [[MASViewConstraint alloc] initWithFirstViewAttribute:firstViewAttribute];
-        viewConstraint.delegate = self.delegate;
-        viewConstraint.layoutRelation = self.layoutRelation;
-        return viewConstraint;
-    }
-    return self;
-}
-
 #pragma mark - NSLayoutConstraint constant proxies
 
 - (id<MASConstraint> (^)(UIEdgeInsets))insets {
@@ -190,40 +178,34 @@
 
 - (id<MASConstraint> (^)(id))equalTo {
     return ^id(id attr) {
-        NSAssert(!self.hasBeenCommitted,
-                 @"Cannot modify constraint equal relation after it has been committed");
+        NSAssert(!self.hasLayoutRelation, @"Redefinition of constraint relation");
         
-        MASViewConstraint *viewConstraint = [self cloneIfNeeded];
-        viewConstraint.layoutRelation = NSLayoutRelationEqual;
-        viewConstraint.secondViewAttribute = attr;
-        [viewConstraint.delegate addConstraint:viewConstraint];
-        return viewConstraint;
+        self.layoutRelation = NSLayoutRelationEqual;
+        self.secondViewAttribute = attr;
+        [self.delegate addConstraint:self];
+        return self;
     };
 }
 
 - (id<MASConstraint> (^)(id))greaterThanOrEqualTo {
     return ^id(id attr) {
-        NSAssert(!self.hasBeenCommitted,
-                 @"Cannot modify constraint greaterThanOrEqual relation after it has been committed");
+        NSAssert(!self.hasLayoutRelation, @"Redefinition of constraint relation");
         
-        MASViewConstraint *viewConstraint = [self cloneIfNeeded];
-        viewConstraint.layoutRelation = NSLayoutRelationGreaterThanOrEqual;
-        viewConstraint.secondViewAttribute = attr;
-        [viewConstraint.delegate addConstraint:viewConstraint];
-        return viewConstraint;
+        self.layoutRelation = NSLayoutRelationGreaterThanOrEqual;
+        self.secondViewAttribute = attr;
+        [self.delegate addConstraint:self];
+        return self;
     };
 }
 
 - (id<MASConstraint> (^)(id))lessThanOrEqualTo {
     return ^id(id attr) {
-        NSAssert(!self.hasBeenCommitted,
-                 @"Cannot modify constraint lessThanOrEqual relation after it has been committed");
+        NSAssert(!self.hasLayoutRelation, @"Redefinition of constraint relation");
         
-        MASViewConstraint *viewConstraint = [self cloneIfNeeded];
-        viewConstraint.layoutRelation = NSLayoutRelationLessThanOrEqual;
-        viewConstraint.secondViewAttribute = attr;
-        [viewConstraint.delegate addConstraint:viewConstraint];
-        return viewConstraint;
+        self.layoutRelation = NSLayoutRelationLessThanOrEqual;
+        self.secondViewAttribute = attr;
+        [self.delegate addConstraint:self];
+        return self;
     };
 }
 

@@ -49,7 +49,6 @@
         [self.animatableConstraints addObjectsFromArray:@[
             make.edges.equalTo(superview).insets(paddingInsets).priorityLow(),
             make.bottom.equalTo(view3.mas_top).offset(-padding),
-            make.right.equalTo(view2.mas_left).offset(-padding),
         ]];
 
         make.size.equalTo(view2);
@@ -70,11 +69,8 @@
     [view3 mas_makeConstraints:^(MASConstraintMaker *make) {
         [self.animatableConstraints addObjectsFromArray:@[
             make.edges.equalTo(superview).insets(paddingInsets).priorityLow(),
-            make.top.equalTo(view1.mas_bottom).offset(padding),
         ]];
 
-        //TODO or pass an array
-        //constraints.height.equal(superview.subviews);
         make.height.equalTo(view1.mas_height);
         make.height.equalTo(view2.mas_height);
     }];
@@ -83,6 +79,7 @@
 }
 
 - (void)didMoveToSuperview {
+    [self layoutIfNeeded];
     [self startAnimatingWithInvertedInsets:NO];
 }
 

@@ -43,11 +43,9 @@
         make.bottom.equalTo(view3.top).offset(-padding);
         make.right.equalTo(view2.left).offset(-padding);
         make.width.equalTo(view2.width);
-        
-        //you can chain same attribute
-        make.height
-            .equalTo(view2.height)
-            .equalTo(view3.height);
+
+        make.height.equalTo(view2.height);
+        make.height.equalTo(view3.height);
     }];
 
     //with is semantic and option
@@ -58,7 +56,6 @@
         make.right.equalTo(superview.mas_right).offset(-padding);
         make.width.equalTo(view1.mas_width);
         
-        //or define it multiple times
         make.height.equalTo(view1.mas_height);
         make.height.equalTo(view3.mas_height);
     }];
@@ -69,12 +66,10 @@
         make.bottom.equalTo(superview.mas_bottom).offset(-padding);
         make.right.equalTo(superview.mas_right).offset(-padding);
         
-        //TODO or pass an array
-        //constraints.height.equal(superview.subviews);
         make.height.equalTo(view1.mas_height);
         make.height.equalTo(view2.mas_height);
     }];
-    
+
     return self;
 }
 

@@ -20,6 +20,7 @@
 @interface MASViewConstraint ()
 
 @property (nonatomic, assign) CGFloat layoutConstant;
+@property (nonatomic, assign) MASLayoutPriority layoutPriority;
 
 @end
 
@@ -100,9 +101,7 @@ it(@"should complete children", ^{
 
     //first equality statement
     composite.equalTo(newView).sizeOffset(CGSizeMake(90, 30));
-
-    [verify(delegate) addConstraint:(id)composite];
-
+    
     expect(composite.completedChildConstraints).to.haveCountOf(2);
     expect(composite.currentChildConstraints).to.haveCountOf(2);
 
@@ -110,38 +109,20 @@ it(@"should complete children", ^{
     expect(viewConstraint.secondViewAttribute.view).to.beIdenticalTo(newView);
     expect(viewConstraint.secondViewAttribute.layoutAttribute).to.equal(NSLayoutAttributeWidth);
     expect(viewConstraint.layoutConstant).to.equal(90);
+    expect(viewConstraint.layoutPriority).to.equal(MASLayoutPriorityRequired);
 
     viewConstraint = composite.completedChildConstraints[1];
     expect(viewConstraint.secondViewAttribute.view).to.beIdenticalTo(newView);
     expect(viewConstraint.secondViewAttribute.layoutAttribute).to.equal(NSLayoutAttributeHeight);
     expect(viewConstraint.layoutConstant).to.equal(30);
+    expect(viewConstraint.layoutPriority).to.equal(MASLayoutPriorityRequired);
 
-    //chain another equality statement
-    composite.greaterThanOrEqualTo(@6);
-    expect(composite.completedChildConstraints).to.haveCountOf(4);
-    expect(composite.currentChildConstraints).to.haveCountOf(2);
-
-    viewConstraint = composite.completedChildConstraints[2];
-    expect(viewConstraint.secondViewAttribute.view).to.beNil();
-    expect(viewConstraint.secondViewAttribute.layoutAttribute).to.equal(0);
-    expect(viewConstraint.layoutConstant).to.equal(6);
-
-    viewConstraint = composite.completedChildConstraints[2];
-    expect(viewConstraint.secondViewAttribute.view).to.beNil();
-    expect(viewConstraint.secondViewAttribute.layoutAttribute).to.equal(0);
-    expect(viewConstraint.layoutConstant).to.equal(6);
-
-    //still referencing same view
-    viewConstraint = composite.currentChildConstraints[0];
-    expect(viewConstraint.firstViewAttribute.view).to.beIdenticalTo(composite.view);
-    expect(viewConstraint.firstViewAttribute.layoutAttribute).to.equal(NSLayoutAttributeWidth);
-
-    viewConstraint = composite.currentChildConstraints[1];
-    expect(viewConstraint.firstViewAttribute.view).to.beIdenticalTo(composite.view);
-    expect(viewConstraint.firstViewAttribute.layoutAttribute).to.equal(NSLayoutAttributeHeight);
+    //new current
+    expect(composite.completedChildConstraints[0]).to.beIdenticalTo(composite.currentChildConstraints[0]);
+    expect(composite.completedChildConstraints[1]).to.beIdenticalTo(composite.currentChildConstraints[1]);
 });
 
-it(@"should remove all on commit", ^{
+it(@"should remove completed on commit", ^{
     composite = [[MASCompositeConstraint alloc] initWithView:view type:MASCompositeViewConstraintTypeSize];
     composite.delegate = delegate;
     UIView *newView = UIView.new;
@@ -158,7 +139,7 @@ it(@"should remove all on commit", ^{
     [composite commit];
 
     expect(composite.completedChildConstraints).to.haveCountOf(0);
-    expect(composite.currentChildConstraints).to.haveCountOf(0);
+    expect(composite.currentChildConstraints).to.haveCountOf(2);
 });
 
 SpecEnd
\ No newline at end of file

@@ -43,9 +43,9 @@ beforeEach(^{
     [superview addSubview:otherView];
 });
 
-describe(@"equality chaining", ^{
+describe(@"create equality constraint", ^{
     
-    it(@"should return same constraint when encountering equal for first time", ^{
+    it(@"should create equal constraint", ^{
         MASViewAttribute *secondViewAttribute = otherView.mas_top;
         MASViewConstraint *newConstraint = constraint.equalTo(secondViewAttribute);
         
@@ -55,17 +55,7 @@ describe(@"equality chaining", ^{
         expect(constraint.layoutRelation).to.equal(NSLayoutRelationEqual);
     });
     
-    it(@"should start new constraint when encountering equal subsequently", ^{
-        MASViewAttribute *secondViewAttribute = otherView.mas_top;
-        constraint.greaterThanOrEqualTo(secondViewAttribute);
-        MASViewConstraint *newConstraint = constraint.equalTo(secondViewAttribute);
-        
-        [verify(constraint.delegate) addConstraint:(id)constraint];
-        [verify(constraint.delegate) addConstraint:(id)newConstraint];
-        expect(newConstraint).notTo.beIdenticalTo(constraint);
-    });
-    
-    it(@"should return same constraint when encountering greaterThanOrEqual for first time", ^{
+    it(@"should create greaterThanOrEqual constraint", ^{
         MASViewAttribute *secondViewAttribute = otherView.mas_top;
         MASViewConstraint *newConstraint = constraint.greaterThanOrEqualTo(secondViewAttribute);
         
@@ -75,17 +65,7 @@ describe(@"equality chaining", ^{
         expect(constraint.layoutRelation).to.equal(NSLayoutRelationGreaterThanOrEqual);
     });
     
-    it(@"should start new constraint when encountering greaterThanOrEqual subsequently", ^{
-        MASViewAttribute *secondViewAttribute = otherView.mas_top;
-        constraint.lessThanOrEqualTo(secondViewAttribute);
-        MASViewConstraint *newConstraint = constraint.greaterThanOrEqualTo(secondViewAttribute);
-        
-        [verify(constraint.delegate) addConstraint:(id)constraint];
-        [verify(constraint.delegate) addConstraint:(id)newConstraint];
-        expect(newConstraint).notTo.beIdenticalTo(constraint);
-    });
-    
-    it(@"should return same constraint when encountering lessThanOrEqual for first time", ^{
+    it(@"create lessThanOrEqual constraint", ^{
         MASViewAttribute *secondViewAttribute = otherView.mas_top;
         MASViewConstraint *newConstraint = constraint.lessThanOrEqualTo(secondViewAttribute);
         
@@ -95,37 +75,27 @@ describe(@"equality chaining", ^{
         expect(constraint.layoutRelation).to.equal(NSLayoutRelationLessThanOrEqual);
     });
     
-    it(@"should start new constraint when encountering lessThanOrEqual subsequently", ^{
+    it(@"should not allow update of equal", ^{
         MASViewAttribute *secondViewAttribute = otherView.mas_top;
-        constraint.equalTo(secondViewAttribute);
-        MASViewConstraint *newConstraint = constraint.lessThanOrEqualTo(secondViewAttribute);
-        
-        [verify(constraint.delegate) addConstraint:(id)constraint];
-        [verify(constraint.delegate) addConstraint:(id)newConstraint];
-        expect(newConstraint).notTo.beIdenticalTo(constraint);
-    });
-    
-    it(@"should not allow update of equal once layoutconstraint is created", ^{
-        MASViewAttribute *secondViewAttribute = otherView.mas_top;
-        [constraint commit];
+        constraint.lessThanOrEqualTo(secondViewAttribute);
         
         expect(^{
             constraint.equalTo(secondViewAttribute);
         }).to.raise(@"NSInternalInconsistencyException");
     });
     
-    it(@"should not allow update of lessThanOrEqual once layoutconstraint is created", ^{
+    it(@"should not allow update of lessThanOrEqual", ^{
         MASViewAttribute *secondViewAttribute = otherView.mas_top;
-        [constraint commit];
+        constraint.equalTo(secondViewAttribute);
         
         expect(^{
             constraint.lessThanOrEqualTo(secondViewAttribute);
         }).to.raise(@"NSInternalInconsistencyException");
     });
     
-    it(@"should not allow update of greaterThanOrEqual once layoutconstraint is created", ^{
+    it(@"should not allow update of greaterThanOrEqual", ^{
         MASViewAttribute *secondViewAttribute = otherView.mas_top;
-        [constraint commit];
+        constraint.greaterThanOrEqualTo(secondViewAttribute);
         
         expect(^{
             constraint.greaterThanOrEqualTo(secondViewAttribute);

@@ -114,7 +114,6 @@ if you want view.left to be greater than or equal to label.left :
 ```obj-c
 //these two constraints are exactly the same
 make.left.greaterThanOrEqualTo(label);
-
 make.left.greaterThanOrEqualTo(label.mas_left);
 ```
 
@@ -123,9 +122,8 @@ make.left.greaterThanOrEqualTo(label.mas_left);
 if you want to set view to have a minimum and maximum width you could pass a number to the equality blocks:
 
 ```obj-c
-make.width
-    .greaterThanOrEqualTo(@200)
-    .lessThanOrEqualTo(@400)
+make.width.greaterThanOrEqualTo(@200);
+make.width.lessThanOrEqualTo(@400)
 ```
 
 ## Learn to prioritize