SnapKit/Tests/SnapKitTests/Tests.swift

#if os(iOS) || os(tvOS)
import UIKit
typealias View = UIView
extension View {
    var snp_constraints: [AnyObject] {
        return self.constraints
            .filter { $0 is LayoutConstraint }
            .filter { $0.isActive }
    }
}
#else
import AppKit
typealias View = NSView
extension View {
    var snp_constraints: [AnyObject] {
        return self.constraints
            .filter { $0 is LayoutConstraint }
            .filter { $0.isActive }
    }
}
#endif

import XCTest
@testable import SnapKit

class SnapKitTests: XCTestCase {
    
    let container = View()
    
    override func setUp() {
        super.setUp()
        // Put setup code here. This method is called before the invocation of each test method in the class.
    }
    
    override func tearDown() {
        // Put teardown code here. This method is called after the invocation of each test method in the class.
        super.tearDown()
    }
    
    func testMakeConstraints() {
        let v1 = View()
        let v2 = View()
        self.container.addSubview(v1)
        self.container.addSubview(v2)
        
        v1.snp.makeConstraints { (make) -> Void in
            make.top.equalTo(v2.snp.top).offset(50)
            make.left.equalTo(v2.snp.top).offset(50)
            return
        }
        
        XCTAssertEqual(self.container.snp_constraints.count, 2, "Should have 2 constraints installed")
        
        v2.snp.makeConstraints { (make) -> Void in
            make.edges.equalTo(v1)
            return
        }
        
        XCTAssertEqual(self.container.snp_constraints.count, 6, "Should have 6 constraints installed")
        
    }
    
    func testGuideMakeConstraints() {
        guard #available(iOS 9.0, OSX 10.11, *) else { return }
        let v1 = View()

        let g1 = ConstraintLayoutGuide()
        self.container.addSubview(v1)
        self.container.addLayoutGuide(g1)
            
        v1.snp.makeConstraints { (make) -> Void in
            make.top.equalTo(g1).offset(50)
            make.left.equalTo(g1.snp.top).offset(50)
            return
        }
            
        XCTAssertEqual(self.container.snp_constraints.count, 2, "Should have 2 constraints installed")
        
        g1.snp.makeConstraints { (make) -> Void in
            make.edges.equalTo(v1)
            return
        }
        
        XCTAssertEqual(self.container.snp_constraints.count, 6, "Should have 6 constraints installed")
    }
    
    func testMakeImpliedSuperviewConstraints() {
        let v1 = View()
        let v2 = View()
        self.container.addSubview(v1)
        self.container.addSubview(v2)
        
        v1.snp.makeConstraints { (make) -> Void in
            make.top.equalTo(50.0)
            make.left.equalTo(50.0)
            return
        }
        
        XCTAssertEqual(self.container.snp_constraints.count, 2, "Should have 2 constraints installed")
        
        v2.snp.makeConstraints { (make) -> Void in
            make.edges.equalTo(v1)
            return
        }
        
        XCTAssertEqual(self.container.snp_constraints.count, 6, "Should have 6 constraints installed")
    }
    
    func testUpdateConstraints() {
        let v1 = View()
        let v2 = View()
        self.container.addSubview(v1)
        self.container.addSubview(v2)
        
        v1.snp.makeConstraints { (make) -> Void in
            make.top.equalTo(v2.snp.top).offset(50)
            make.left.equalTo(v2.snp.top).offset(50)
            return
        }
        
        XCTAssertEqual(self.container.snp_constraints.count, 2, "Should have 2 constraints installed")
        
        v1.snp.updateConstraints { (make) -> Void in
            make.top.equalTo(v2.snp.top).offset(15)
            return
        }
        
        XCTAssertEqual(self.container.snp_constraints.count, 2, "Should still have 2 constraints installed")
        
    }
    
    func testRemakeConstraints() {
        let v1 = View()
        let v2 = View()
        self.container.addSubview(v1)
        self.container.addSubview(v2)
        
        v1.snp.makeConstraints { (make) -> Void in
            make.top.equalTo(v2.snp.top).offset(50)
            make.left.equalTo(v2.snp.top).offset(50)
            return
        }
        
        XCTAssertEqual(self.container.snp_constraints.count, 2, "Should have 2 constraints installed")
        
        v1.snp.remakeConstraints { (make) -> Void in
            make.edges.equalTo(v2)
            return
        }
        
        XCTAssertEqual(self.container.snp_constraints.count, 4, "Should have 4 constraints installed")
        
    }
    
    func testRemoveConstraints() {
        let v1 = View()
        let v2 = View()
        self.container.addSubview(v1)
        self.container.addSubview(v2)
        
        v1.snp.makeConstraints { (make) -> Void in
            make.top.equalTo(v2).offset(50)
            make.left.equalTo(v2).offset(50)
            return
        }
        
        XCTAssertEqual(self.container.snp_constraints.count, 2, "Should have 2 constraints installed")
        
        print(self.container.snp_constraints)
        
        v1.snp.removeConstraints()
        
        print(self.container.snp_constraints)
        
        XCTAssertEqual(self.container.snp_constraints.count, 0, "Should have 0 constraints installed")
        
    }
    
    func testPrepareConstraints() {
        let v1 = View()
        let v2 = View()
        self.container.addSubview(v1)
        self.container.addSubview(v2)
        
        let constraints = v1.snp.prepareConstraints { (make) -> Void in
            make.edges.equalTo(v2)
            return
        }
        
        XCTAssertEqual(self.container.snp_constraints.count, 0, "Should have 0 constraints installed")
        
        for constraint in constraints {
            constraint.activate()
        }
        
        XCTAssertEqual(self.container.snp_constraints.count, 4, "Should have 4 constraints installed")
        
        for constraint in constraints {
            constraint.deactivate()
        }
        
        XCTAssertEqual(self.container.snp_constraints.count, 0, "Should have 0 constraints installed")
        
    }
    
    func testReactivateConstraints() {
        let v1 = View()
        let v2 = View()
        self.container.addSubview(v1)
        self.container.addSubview(v2)
        
        let constraints = v1.snp.prepareConstraints { (make) -> Void in
            make.edges.equalTo(v2)
            return
        }
        
        
        XCTAssertEqual(self.container.snp_constraints.count, 0, "Should have 0 constraints installed")
        
        for constraint in constraints {
            constraint.activate()
        }
        
        XCTAssertEqual(self.container.snp_constraints.count, 4, "Should have 4 constraints installed")
        
        for constraint in constraints {
            constraint.deactivate()
        }
        
        XCTAssertEqual(self.container.snp_constraints.count, 0, "Should have 0 constraints installed")
    }
    
    func testActivateDeactivateConstraints() {
        let v1 = View()
        let v2 = View()
        self.container.addSubview(v1)
        self.container.addSubview(v2)
        
        var c1: Constraint? = nil
        var c2: Constraint? = nil
        
        v1.snp.prepareConstraints { (make) -> Void in
            c1 = make.top.equalTo(v2.snp.top).offset(50).constraint
            c2 = make.left.equalTo(v2.snp.top).offset(50).constraint
            return
        }
        
        XCTAssertEqual(self.container.snp_constraints.count, 0, "Should have 0 constraints")
        
        c1?.activate()
        c2?.activate()
        
        XCTAssertEqual(self.container.snp_constraints.count, 2, "Should have 2 constraints")
        
        c1?.deactivate()
        c2?.deactivate()
        
        XCTAssertEqual(self.container.snp_constraints.count, 0, "Should have 0 constraints")
        
        c1?.activate()
        c2?.activate()
        
        XCTAssertEqual(self.container.snp_constraints.count, 2, "Should have 2 constraints")
        
    }
    
    func testSetIsActivatedConstraints() {
        let v1 = View()
        let v2 = View()
        self.container.addSubview(v1)
        self.container.addSubview(v2)
        
        var c1: Constraint? = nil
        var c2: Constraint? = nil
        
        v1.snp.prepareConstraints { (make) -> Void in
            c1 = make.top.equalTo(v2.snp.top).offset(50).constraint
            c2 = make.left.equalTo(v2.snp.top).offset(50).constraint
            return
        }
        
        XCTAssertEqual(self.container.snp_constraints.count, 0, "Should have 0 constraints")
        
        c1?.isActive = true
        c2?.isActive = false
        
        XCTAssertEqual(self.container.snp_constraints.count, 1, "Should have 1 constraint")
        
        c1?.isActive = true
        c2?.isActive = true
        
        XCTAssertEqual(self.container.snp_constraints.count, 2, "Should have 2 constraints")
        
        c1?.isActive = false
        c2?.isActive = false
        
        XCTAssertEqual(self.container.snp_constraints.count, 0, "Should have 0 constraints")
        
    }
    
    func testEdgeConstraints() {
        let view = View()
        self.container.addSubview(view)
        
        view.snp.makeConstraints { (make) -> Void in
            make.edges.equalTo(self.container).offset(50.0)
        }
        
        XCTAssertEqual(self.container.snp_constraints.count, 4, "Should have 4 constraints")
        
        
        let constraints = self.container.snp_constraints as! [NSLayoutConstraint]
        
        XCTAssertEqual(constraints[0].constant, 50, "Should be 50")
        XCTAssertEqual(constraints[1].constant, 50, "Should be 50")
        XCTAssertEqual(constraints[2].constant, 50, "Should be 50")
        XCTAssertEqual(constraints[3].constant, 50, "Should be 50")
    }
    
    func testUpdateReferencedConstraints() {
        let v1 = View()
        let v2 = View()
        self.container.addSubview(v1)
        self.container.addSubview(v2)
        
        var c1: Constraint! = nil
        var c2: Constraint! = nil
        
        v1.snp.makeConstraints { (make) -> Void in
            c1 = make.top.equalTo(v2).offset(50).constraint
            c2 = make.bottom.equalTo(v2).offset(25).constraint
            return
        }
        
        XCTAssertEqual(self.container.snp_constraints.count, 2, "Should have 2 constraints")
        
        let constraints = (self.container.snp_constraints as! [NSLayoutConstraint]).sorted { $0.constant > $1.constant }
        
        XCTAssertEqual(constraints[0].constant, 50, "Should be 50")
        XCTAssertEqual(constraints[1].constant, 25, "Should be 25")
        
        c1.update(offset: 15)
        c2.update(offset: 20)
        
        XCTAssertEqual(self.container.snp_constraints.count, 2, "Should have 2 constraints")
        
        XCTAssertEqual(constraints[0].constant, 15, "Should be 15")
        XCTAssertEqual(constraints[1].constant, 20, "Should be 20")
        
        c1.update(inset: 15)
        c2.update(inset: 20)
        
        XCTAssertEqual(self.container.snp_constraints.count, 2, "Should have 2 constraints")
        
        XCTAssertEqual(constraints[0].constant, 15, "Should be 15")
        XCTAssertEqual(constraints[1].constant, -20, "Should be -20")
        
    }
    
    func testInsetsAsConstraintsConstant() {
        let view = View()
        self.container.addSubview(view)
        
        view.snp.makeConstraints { (make) -> Void in
            make.edges.equalTo(self.container).inset(50.0)
        }
        
        XCTAssertEqual(self.container.snp_constraints.count, 4, "Should have 4 constraints")
        
        let constraints = (self.container.snp_constraints as! [NSLayoutConstraint]).sorted { $0.constant > $1.constant }
        
        XCTAssertEqual(constraints[0].constant, 50, "Should be 50")
        XCTAssertEqual(constraints[1].constant, 50, "Should be 50")
        XCTAssertEqual(constraints[2].constant, -50, "Should be -50")
        XCTAssertEqual(constraints[3].constant, -50, "Should be -50")
    }
    
    func testConstraintInsetsAsImpliedEqualToConstraints() {
        let view = View()
        self.container.addSubview(view)
        
        view.snp.makeConstraints { (make) -> Void in
            make.edges.equalTo(ConstraintInsets(top: 25, left: 25, bottom: 25, right: 25))
        }
        
        XCTAssertEqual(self.container.snp_constraints.count, 4, "Should have 4 constraints")
        
        
        let constraints = (self.container.snp_constraints as! [NSLayoutConstraint]).sorted { $0.constant > $1.constant }
        
        XCTAssertEqual(constraints[0].constant, 25, "Should be 25")
        XCTAssertEqual(constraints[1].constant, 25, "Should be 25")
        XCTAssertEqual(constraints[2].constant, -25, "Should be -25")
        XCTAssertEqual(constraints[3].constant, -25, "Should be -25")
    }
    
    func testConstraintInsetsAsConstraintsConstant() {
        let view = View()
        self.container.addSubview(view)
        
        view.snp.makeConstraints { (make) -> Void in
            make.edges.equalTo(self.container).inset(ConstraintInsets(top: 25, left: 25, bottom: 25, right: 25))
        }
        
        XCTAssertEqual(self.container.snp_constraints.count, 4, "Should have 4 constraints")
        
        
        let constraints = (self.container.snp_constraints as! [NSLayoutConstraint]).sorted { $0.constant > $1.constant }
        
        XCTAssertEqual(constraints[0].constant, 25, "Should be 25")
        XCTAssertEqual(constraints[1].constant, 25, "Should be 25")
        XCTAssertEqual(constraints[2].constant, -25, "Should be -25")
        XCTAssertEqual(constraints[3].constant, -25, "Should be -25")
    }
    
    #if os(iOS) || os(tvOS)
    @available(iOS 11.0, tvOS 11.0, *)
    func testConstraintDirectionalInsetsAsImpliedEqualToConstraints() {
        let view = View()
        self.container.addSubview(view)

        view.snp.makeConstraints { (make) -> Void in
            make.top.leading.bottom.trailing.equalTo(self.container).inset(ConstraintDirectionalInsets(top: 25, leading: 25, bottom: 25, trailing: 25))
        }

        XCTAssertEqual(self.container.snp_constraints.count, 4, "Should have 4 constraints")


        let constraints = (self.container.snp_constraints as! [NSLayoutConstraint]).sorted { $0.firstAttribute.rawValue < $1.firstAttribute.rawValue }

        let verify: (NSLayoutConstraint, NSLayoutConstraint.Attribute, CGFloat) -> Void = { constraint, attribute, constant in
          XCTAssertEqual(constraint.firstAttribute, attribute, "First attribute \(constraint.firstAttribute.rawValue) is not \(attribute.rawValue)")
          XCTAssertEqual(constraint.secondAttribute, attribute, "Second attribute \(constraint.secondAttribute.rawValue) is not \(attribute.rawValue)")
          XCTAssertEqual(constraint.constant, constant, "Attribute \(attribute.rawValue) should have constant \(constant)")
        }

        verify(constraints[0], .top, 25)
        verify(constraints[1], .bottom, -25)
        verify(constraints[2], .leading, 25)
        verify(constraints[3], .trailing, -25)
    }
    #endif

    #if os(iOS) || os(tvOS)
    @available(iOS 11.0, tvOS 11.0, *)
    func testConstraintDirectionalInsetsAsConstraintsConstant() {
        let view = View()
        self.container.addSubview(view)

        view.snp.makeConstraints { (make) -> Void in
            make.top.leading.bottom.trailing.equalTo(self.container).inset(ConstraintDirectionalInsets(top: 25, leading: 25, bottom: 25, trailing: 25))
        }

        XCTAssertEqual(self.container.snp_constraints.count, 4, "Should have 4 constraints")


        let constraints = (self.container.snp_constraints as! [NSLayoutConstraint]).sorted { $0.firstAttribute.rawValue < $1.firstAttribute.rawValue }

        let verify: (NSLayoutConstraint, NSLayoutConstraint.Attribute, CGFloat) -> Void = { constraint, attribute, constant in
            XCTAssertEqual(constraint.firstAttribute, attribute, "First attribute \(constraint.firstAttribute.rawValue) is not \(attribute.rawValue)")
            XCTAssertEqual(constraint.secondAttribute, attribute, "Second attribute \(constraint.secondAttribute.rawValue) is not \(attribute.rawValue)")
            XCTAssertEqual(constraint.constant, constant, "Attribute \(attribute.rawValue) should have constant \(constant)")
        }

        verify(constraints[0], .top, 25)
        verify(constraints[1], .bottom, -25)
        verify(constraints[2], .leading, 25)
        verify(constraints[3], .trailing, -25)
    }
    #endif

    #if os(iOS) || os(tvOS)
    @available(iOS 11.0, tvOS 11.0, *)
    func testConstraintDirectionalInsetsFallBackForNonDirectionalConstraints() {
        let view = View()
        self.container.addSubview(view)

        view.snp.makeConstraints { (make) -> Void in
            make.edges.equalTo(self.container).inset(ConstraintDirectionalInsets(top: 25, leading: 25, bottom: 25, trailing: 25))
        }

        XCTAssertEqual(self.container.snp_constraints.count, 4, "Should have 4 constraints")


        let constraints = (self.container.snp_constraints as! [NSLayoutConstraint]).sorted { $0.firstAttribute.rawValue < $1.firstAttribute.rawValue }

        let verify: (NSLayoutConstraint, NSLayoutConstraint.Attribute, CGFloat) -> Void = { constraint, attribute, constant in
            XCTAssertEqual(constraint.firstAttribute, attribute, "First attribute \(constraint.firstAttribute.rawValue) is not \(attribute.rawValue)")
            XCTAssertEqual(constraint.secondAttribute, attribute, "Second attribute \(constraint.secondAttribute.rawValue) is not \(attribute.rawValue)")
            XCTAssertEqual(constraint.constant, constant, "Attribute \(attribute.rawValue) should have constant \(constant)")
        }

        verify(constraints[0], .left, 25)
        verify(constraints[1], .right, -25)
        verify(constraints[2], .top, 25)
        verify(constraints[3], .bottom, -25)
    }
    #endif

    func testSizeConstraints() {
        let view = View()
        self.container.addSubview(view)
        
        view.snp.makeConstraints { (make) -> Void in
            make.size.equalTo(CGSize(width: 50, height: 50))
            make.left.top.equalTo(self.container)
        }
        
        XCTAssertEqual(view.snp_constraints.count, 2, "Should have 2 constraints")
        
        XCTAssertEqual(self.container.snp_constraints.count, 2, "Should have 2 constraints")
        
        let constraints = view.snp_constraints as! [NSLayoutConstraint]

        // no guarantee which order the constraints are in, but we should test their couple
        let widthHeight = (LayoutAttribute.width.rawValue, LayoutAttribute.height.rawValue)
        let heightWidth = (widthHeight.1, widthHeight.0)
        let firstSecond = (constraints[0].firstAttribute.rawValue, constraints[1].firstAttribute.rawValue)

        // constraint values are correct in either width, height or height, width order
        XCTAssertTrue(firstSecond == widthHeight || firstSecond == heightWidth, "2 contraint values should match")
        XCTAssertEqual(constraints[0].constant, 50, "Should be 50")
        XCTAssertEqual(constraints[1].constant, 50, "Should be 50")
    }
    
    func testCenterConstraints() {
        let view = View()
        self.container.addSubview(view)
        
        view.snp.makeConstraints { (make) -> Void in
            make.center.equalTo(self.container).offset(50.0)
        }
        
        XCTAssertEqual(self.container.snp_constraints.count, 2, "Should have 2 constraints")
        
        
        if let constraints = self.container.snp_constraints as? [NSLayoutConstraint], constraints.count > 0 {
        
            XCTAssertEqual(constraints[0].constant, 50, "Should be 50")
            XCTAssertEqual(constraints[1].constant, 50, "Should be 50")
        }
    }
    
    func testConstraintIdentifier() {
        let identifier = "Test-Identifier"
        let view = View()
        self.container.addSubview(view)
        
        view.snp.makeConstraints { (make) -> Void in
            make.top.equalTo(self.container.snp.top).labeled(identifier)
        }
        
        let constraints = container.snp_constraints as! [NSLayoutConstraint]
        XCTAssertEqual(constraints[0].identifier, identifier, "Identifier should be 'Test'")
    }
    
    func testEdgesToEdges() {
        var fromAttributes = Set<LayoutAttribute>()
        var toAttributes = Set<LayoutAttribute>()
        
        let view = View()
        self.container.addSubview(view)
        
        view.snp.remakeConstraints { (make) -> Void in
            make.edges.equalTo(self.container.snp.edges)
        }
        
        XCTAssertEqual(self.container.snp_constraints.count, 4, "Should have 4 constraints")
        
        for constraint in (container.snp_constraints as! [NSLayoutConstraint]) {
            fromAttributes.insert(constraint.firstAttribute)
            toAttributes.insert(constraint.secondAttribute)
        }
        
        XCTAssert(fromAttributes == [.top, .left, .bottom, .right])
        XCTAssert(toAttributes == [.top, .left, .bottom, .right])
    }

    func testDirectionalEdgesToDirectionalEdges() {
        var fromAttributes = Set<LayoutAttribute>()
        var toAttributes = Set<LayoutAttribute>()
        
        let view = View()
        self.container.addSubview(view)
        
        view.snp.remakeConstraints { (make) -> Void in
            make.directionalEdges.equalTo(self.container.snp.directionalEdges)
        }
        
        XCTAssertEqual(self.container.snp_constraints.count, 4, "Should have 4 constraints")
        
        for constraint in (container.snp_constraints as! [NSLayoutConstraint]) {
            fromAttributes.insert(constraint.firstAttribute)
            toAttributes.insert(constraint.secondAttribute)
        }
        
        XCTAssert(fromAttributes == [.top, .leading, .bottom, .trailing])
        XCTAssert(toAttributes == [.top, .leading, .bottom, .trailing])
    }
    
    #if os(iOS) || os(tvOS)
    func testEdgesToMargins() {
        var fromAttributes = Set<LayoutAttribute>()
        var toAttributes = Set<LayoutAttribute>()
        
        let view = View()
        self.container.addSubview(view)
        
        view.snp.remakeConstraints { (make) -> Void in
            make.edges.equalTo(self.container.snp.margins)
        }
        
        XCTAssertEqual(self.container.snp_constraints.count, 4, "Should have 4 constraints")
        
        for constraint in (container.snp_constraints as! [NSLayoutConstraint]) {
            fromAttributes.insert(constraint.firstAttribute)
            toAttributes.insert(constraint.secondAttribute)
        }
        
        XCTAssert(fromAttributes == [.top, .left, .bottom, .right])
        XCTAssert(toAttributes == [.topMargin, .leftMargin, .bottomMargin, .rightMargin])
        
        fromAttributes.removeAll()
        toAttributes.removeAll()
        
        view.snp.remakeConstraints { (make) -> Void in
            make.margins.equalTo(self.container.snp.edges)
        }
        
        XCTAssertEqual(self.container.snp_constraints.count, 4, "Should have 4 constraints")
        
        for constraint in (container.snp_constraints as! [NSLayoutConstraint]) {
            fromAttributes.insert(constraint.firstAttribute)
            toAttributes.insert(constraint.secondAttribute)
        }
        
        XCTAssert(toAttributes == [.top, .left, .bottom, .right])
        XCTAssert(fromAttributes == [.topMargin, .leftMargin, .bottomMargin, .rightMargin])
        
    }

    func testDirectionalEdgesToDirectionalMargins() {
        var fromAttributes = Set<LayoutAttribute>()
        var toAttributes = Set<LayoutAttribute>()
        
        let view = View()
        self.container.addSubview(view)
        
        view.snp.remakeConstraints { (make) -> Void in
            make.directionalEdges.equalTo(self.container.snp.directionalMargins)
        }
        
        XCTAssertEqual(self.container.snp_constraints.count, 4, "Should have 4 constraints")
        
        for constraint in (container.snp_constraints as! [NSLayoutConstraint]) {
            fromAttributes.insert(constraint.firstAttribute)
            toAttributes.insert(constraint.secondAttribute)
        }
        
        XCTAssert(fromAttributes == [.top, .leading, .bottom, .trailing])
        XCTAssert(toAttributes == [.topMargin, .leadingMargin, .bottomMargin, .trailingMargin])
        
        fromAttributes.removeAll()
        toAttributes.removeAll()
        
        view.snp.remakeConstraints { (make) -> Void in
            make.directionalMargins.equalTo(self.container.snp.directionalEdges)
        }
        
        XCTAssertEqual(self.container.snp_constraints.count, 4, "Should have 4 constraints")
        
        for constraint in (container.snp_constraints as! [NSLayoutConstraint]) {
            fromAttributes.insert(constraint.firstAttribute)
            toAttributes.insert(constraint.secondAttribute)
        }
        
        XCTAssert(toAttributes == [.top, .leading, .bottom, .trailing])
        XCTAssert(fromAttributes == [.topMargin, .leadingMargin, .bottomMargin, .trailingMargin])
        
    }
    
    func testLayoutGuideConstraints() {
        let vc = UIViewController()
        vc.view = UIView(frame: CGRect(x: 0, y: 0, width: 300, height: 300))
        
        vc.view.addSubview(self.container)
        
        self.container.snp.makeConstraints { (make) -> Void in
            make.top.equalTo(vc.topLayoutGuide.snp.bottom)
            make.bottom.equalTo(vc.bottomLayoutGuide.snp.top)
        }
         
        XCTAssertEqual(vc.view.snp_constraints.count, 2, "Should have 2 constraints installed")
    }
    #endif
    
    func testCanSetLabel() {
        self.container.snp.setLabel("Hello World")
    }
    
    func testPriorityShortcuts() {
        let view = View()
        self.container.addSubview(view)
        
        view.snp.remakeConstraints { make in
            make.left.equalTo(1000.0).priority(.required)
        }
        XCTAssertEqual(self.container.snp_constraints.count, 1, "Should have 1 constraint")
        XCTAssertEqual(self.container.snp_constraints.first?.priority, ConstraintPriority.required.value)
        
        view.snp.remakeConstraints { make in
            make.left.equalTo(1000.0).priority(.low)
        }
        XCTAssertEqual(self.container.snp_constraints.count, 1, "Should have 1 constraint")
        XCTAssertEqual(self.container.snp_constraints.first?.priority, ConstraintPriority.low.value)
        
        view.snp.remakeConstraints { make in
            make.left.equalTo(1000.0).priority(ConstraintPriority.low.value + 1)
        }
        XCTAssertEqual(self.container.snp_constraints.count, 1, "Should have 1 constraint")
        XCTAssertEqual(self.container.snp_constraints.first?.priority, ConstraintPriority.low.value + 1)
    }

    func testPriorityStride() {
        let highPriority: ConstraintPriority = .high
        let higherPriority: ConstraintPriority = ConstraintPriority.high.advanced(by: 1)
        XCTAssertEqual(higherPriority.value, highPriority.value + 1)
    }
}