Swift·Swift from optionals to SwiftUI

Testing

Test models with XCTest and async code with expectations.

Beginner 13 min read Lesson 9 of 300 Challenge included

What you will be able to do

Test pure models without a simulator.
Use XCTAssertEqual and XCTAssertThrowsError.
Use async test methods for await.
Name tests by the behaviour they protect.

In plain English

Keep business logic in plain Swift types so tests are fast. XCTest supports async tests directly. Test behaviour and edge cases, not private implementation details.

LessonTests.swiftSwift

import XCTest

final class LessonTests: XCTestCase {
    func testShortLessonClassification() {
        XCTAssertEqual(classify(minutes: 9), "short")
    }
}

Your turn

Write an assertion

Easy

Assert that classify(minutes: 9) equals "short".

SWIFT · starter

XCTAssertEqual()

Check your understanding before moving on.

Knowledge checkQuestion 1

Which assertion checks equality in XCTest?

Select an answer to continue

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