Codable.swift

import XCTest

private func _measure(times: UInt64 = 2_000_000, label: String = #function, _ action: (() -> UInt64) -> Void) {
	var result: UInt64 = 0
	var minResult: UInt64 = .max

	for i in 0 ..< times {
		var start: UInt64!
		action {
			start = mach_absolute_time()
			return i
		}
		let end = mach_absolute_time()

		let r = (end - start)
		result += r
		minResult = min(minResult, r)
	}

	var base = mach_timebase_info()
	_ = withUnsafeMutablePointer(to: &base, mach_timebase_info)

	let ns = (result / times) / UInt64(base.denom) * UInt64(base.numer)
	let minNs = minResult / UInt64(base.denom) * UInt64(base.numer)

	print("@\(label): avg \(ns) ns; min \(minNs) ns")
}

private func _measureAndStart(times: UInt64 = 2_000_000, label: String = #function, _ action: () -> Void) {
	return _measure(times: times, label: label) { start in
		_ = start()
		action()
	}
}

struct TestData: Codable {
	enum Gender: String, Codable {
		case male
		case female
	}

	let firstName = "hello"
	let lastName = "hello"
	let gender = Gender.male
	let email = "a@b.com"
	let id = 123456
	let preferredNetwork = 2
	let avatarPath = "/avatar/123456"

	var jsonObject: Any {
		return ["firstName": firstName,
		        "lastName": lastName,
		        "gender": Gender.male.rawValue,
		        "email": email,
		        "id": id,
		        "preferredNetwork": preferredNetwork,
		        "avatarPath": avatarPath] as [String: Any]
	}
}

class Test: XCTestCase {
	func testMappable() {
		_measureAndStart(times: 250_000) {
			_ = try! JSONSerialization.data(withJSONObject: TestData().jsonObject, options: [])
		}
	}

	func testCodable() {
		_measureAndStart(times: 250_000) {
			_ = try! JSONEncoder().encode(TestData())
		}
	}

	func testMappableDec() {
		let data = try! JSONSerialization.data(withJSONObject: TestData().jsonObject, options: [])

		_measureAndStart(times: 250_000) {
			_ = try! JSONSerialization.jsonObject(with: data, options: [])
		}
	}

	func testCodableDec() {
		let data = try! JSONEncoder().encode(TestData())

		_measureAndStart(times: 250_000) {
			_ = try! JSONDecoder().decode(TestData.self, from: data)
		}
	}
}