iPhone 本机应用程序的测试驱动设计

swift
// Calculator.swift
class Calculator {
    func add(_ a: Int, _ b: Int) -> Int {
        return a + b
    }
}

swift
// CalculatorTests.swift
import XCTest
@testable import YourApp
class CalculatorTests: XCTestCase {
    var calculator: Calculator!
    override func setUp() {
        super.setUp()
        calculator = Calculator()
    }
    func testAdd() {
        let result = calculator.add(2, 3)
        XCTAssertEqual(result, 5)
    }
}