         x = view1[.Width] <= 12 * view2[.Width] + 34
         XCTAssertTrue(x.isKindOfClass(NSLayoutConstraint))
         XCTAssertTrue(view1.isEqual(x.firstItem))
-        XCTAssertEqual(x.firstAttribute, .Width)
-        XCTAssertEqual(x.relation, .LessThanOrEqual)
+        XCTAssertEqual(x.firstAttribute, NSLayoutAttribute.Width)
+        XCTAssertEqual(x.relation, NSLayoutRelation.LessThanOrEqual)
         XCTAssertTrue(view2.isEqual(x.secondItem))
-        XCTAssertEqual(x.secondAttribute, .Width)
+        XCTAssertEqual(x.secondAttribute, NSLayoutAttribute.Width)
         XCTAssertEqual(x.multiplier, CGFloat(12))
         XCTAssertEqual(x.constant, CGFloat(34))
     }

        x = 1234 >= view1[.Width]
        XCTAssertTrue(x.isKindOfClass(NSLayoutConstraint))
        XCTAssertTrue(view1.isEqual(x.firstItem))
        XCTAssertEqual(x.firstAttribute, .Width)
        XCTAssertEqual(x.relation, .LessThanOrEqual)
        XCTAssertNil(x.secondItem)
        XCTAssertEqual(x.secondAttribute, .NotAnAttribute)
        XCTAssertEqual(x.multiplier, CGFloat(1))
        XCTAssertEqual(x.constant, CGFloat(1234))
    }

        x = view1[.Width] == 12 * view2[.Width] + 34
        XCTAssertTrue(x.isKindOfClass(NSLayoutConstraint))
        XCTAssertTrue(view1.isEqual(x.firstItem))
        XCTAssertEqual(x.firstAttribute, NSLayoutAttribute.Width)
        XCTAssertEqual(x.relation, NSLayoutRelation.Equal)
        XCTAssertTrue(view2.isEqual(x.secondItem))
        XCTAssertEqual(x.secondAttribute, NSLayoutAttribute.Width)
        XCTAssertEqual(x.multiplier, CGFloat(12))
        XCTAssertEqual(x.constant, CGFloat(34))
    }
