[Xcode/Swift] Quick/Nimbleって何者？ポケモンで覚えるSwiftテストの基本Matcherたち

import Quick
import Nimble
import Foundation

struct Pokemon: Equatable {
    let name: String
    let level: Int
    let type: String
    let evolution: String?
    let team: [String]
    let isLegendary: Bool
}

final class PokemonSpec: QuickSpec {
    override class func spec() {
        describe("Pokemon Matcher Examples") {
            var pikachu: Pokemon!
            var mewtwo: Pokemon!
            var emptyTeam: [String]!

            beforeEach {
                pikachu = Pokemon(
                    name: "Pikachu",
                    level: 25,
                    type: "Electric",
                    evolution: "Raichu",
                    team: ["Bulbasaur", "Charmander", "Squirtle"],
                    isLegendary: false
                )

                mewtwo = Pokemon(
                    name: "Mewtwo",
                    level: 70,
                    type: "Psychic",
                    evolution: nil,
                    team: [],
                    isLegendary: true
                )

                emptyTeam = []
            }

            // 値の比較
            context("Level Comparison") {
                it("ミュウツーのレベルはピカチュウより高い、ピカチュウのレベルは25") {
                    expect(mewtwo.level).to(beGreaterThan(pikachu.level))
                    expect(pikachu.level).to(equal(25))
                }
            }

            // 存在と空チェック
            context("Team and Evolution Checks") {
                it("nilと空をチェック") {
                    expect(mewtwo.evolution).to(beNil())
                    expect(emptyTeam).to(beEmpty())
                    expect(pikachu.team).to(contain("Bulbasaur"))
                }
            }

            // 真偽チェック
            context("Legendary Status") {
                it("ミュウツーは伝説のポケモンである、ピカチュウはそうではない") {
                    expect(mewtwo.isLegendary).to(beTrue())
                    expect(pikachu.isLegendary).to(beFalse())
                }
            }

            // 非同期チェック (簡易版)
            context("Asynchronous Test With toEventually") {
                it("ピカチュウは進化する") {
                    var evolvingPikachu: Pokemon? = nil
                    DispatchQueue.main.asyncAfter(deadline: .now() + 0.5) {
                        evolvingPikachu = pikachu
                    }
                    expect(evolvingPikachu?.name).toEventually(equal("Pikachu"))
                    expect(evolvingPikachu?.evolution).toEventuallyNot(beNil())
                }
            }

            // 条件チェック & 同一インスタンス
            context("Advanced Matchers") {
                it("特定のConditionを満たすピカチュウ") {
                    expect(pikachu.level >= 20 && pikachu.type == "Electric").to(beTrue())
                }

                it("同一インスタンスのチェック") {
                    let sameMewTwo = mewtwo
                    expect(mewtwo).to(equal(sameMewTwo))
                }
            }
        }
    }
}