louisdh/bezierpath-length

//
//  BezierPathLengthTests.swift
//  BezierPathLengthTests
//
//  Created by Louis D'hauwe on 18/11/2016.
//  Copyright © 2016 Silver Fox. All rights reserved.
//

import XCTest
@testable import BezierPathLength

class BezierPathLengthTests: XCTestCase {

    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 testLinearDistance() {

        let a = CGPoint(x: 1, y: 1)
        let b = CGPoint(x: 4, y: 5)

        let distance = a.distance(to: b)

        assert(distance == 5.0, "Distance was incorrect")
    }

    func testSubpath() {

        let path = UIBezierPath()
        path.move(to: .zero)
        path.addLine(to: CGPoint(x: 100, y: 0))
        path.addLine(to: CGPoint(x: 100, y: 100))
        path.addLine(to: CGPoint(x: 0, y: 100))
        path.close()
        path.move(to: CGPoint(x: 100, y: 100))
        path.addLine(to: CGPoint(x: 200, y: 100))
        path.addLine(to: CGPoint(x: 200, y: 200))
        path.addLine(to: CGPoint(x: 100, y: 200))
        path.close()

        let length = path.length

        assert(length == 800.0, "Length was incorrect")

        let halfPoint = path.point(at: 0.5)

        let expectedPoint = CGPoint(x: 0, y: 0)

        assert(halfPoint == expectedPoint, "Point was incorrect")

    }

    func testSubpathEndPoint() {

        let path = UIBezierPath()
        path.move(to: .zero)
        path.addLine(to: CGPoint(x: 100, y: 0))
        path.addLine(to: CGPoint(x: 100, y: 100))
        path.addLine(to: CGPoint(x: 0, y: 100))
        path.close()
        path.move(to: CGPoint(x: 100, y: 100))
        path.addLine(to: CGPoint(x: 200, y: 100))
        path.addLine(to: CGPoint(x: 200, y: 200))
        path.addLine(to: CGPoint(x: 100, y: 200))
        path.close()

        let halfPoint = path.point(at: 1.0)

        let expectedPoint = CGPoint(x: 100, y: 100)

        assert(halfPoint == expectedPoint, "Point was incorrect")

    }

    func testInvalidPath() {

        let path = UIBezierPath()
        path.addLine(to: CGPoint(x: 100, y: 0))

        let length = path.length

        assert(length == 0.0, "Length was incorrect")

        let point = path.point(at: 0.0)

        assert(point == nil, "Point was incorrect")

    }

    func testInvalidPoint() {

        let rect = CGRect(origin: .zero, size: CGSize(width: 100, height: 100))
        let path = UIBezierPath(rect: rect)

        let point = path.point(at: -1.0)

        assert(point == nil, "Point was incorrect")

    }

    func testRectangle() {

        let rect = CGRect(origin: .zero, size: CGSize(width: 100, height: 100))
        let path = UIBezierPath(rect: rect)
        let cgPath = path.cgPath

        assert(path.length == cgPath.length, "Length was incorrect")

        let length = path.length

        assert(length == 400.0, "Length was incorrect")

        let halfPoint = path.point(at: 0.5)

        assert(halfPoint == cgPath.point(at: 0.5), "Point was incorrect")

        let expectedPoint = CGPoint(x: 100, y: 100)

        assert(halfPoint == expectedPoint, "Point was incorrect")

    }

    func testCirlce() {

        let rect = CGRect(origin: .zero, size: CGSize(width: 100, height: 100))
        let path = UIBezierPath(ovalIn: rect)
        let cgPath = path.cgPath

        assert(path.length == cgPath.length, "Length was incorrect")

        let length = path.length

        assert(length == 314.20010500714841, "Length was incorrect")

        let halfPoint = path.point(at: 0.5)

        assert(halfPoint == cgPath.point(at: 0.5), "Point was incorrect")

        let expectedPoint = CGPoint(x: 0.0000000000000000000000000000087922669965178421, y: 49.999999999999972)

        assert(halfPoint == expectedPoint, "Point was incorrect")

    }

    func testLoop() {

        let loopPath = UIBezierPath()

        loopPath.move(to: CGPoint(x: 100, y: 100))
        loopPath.addQuadCurve(to: CGPoint(x: 140, y: 20), controlPoint: CGPoint(x: 150, y: 200))
        loopPath.addQuadCurve(to: CGPoint(x: 240, y: 120), controlPoint: CGPoint(x: 50, y: 300))

        let cgPath = loopPath.cgPath

        assert(loopPath.length == cgPath.length, "Length was incorrect")

        let length = loopPath.length

        assert(length == 482.2257336303885, "Length was incorrect")

        let halfPoint = loopPath.point(at: 0.5)

        assert(halfPoint == cgPath.point(at: 0.5), "Point was incorrect")

        let expectedPoint = CGPoint(x: 113.15372180142839, y: 126.26246219188792)

        assert(halfPoint == expectedPoint, "Point was incorrect")

    }

}