/swift-testing-cheat-sheet

swift-testing cheat sheet

swift-testing-cheat-sheet

The description and example code snippet is taken from Apple document.
For more information, see the Migrating a test from XCTest article.

What is Swift Testing?

  • Define test functions almost anywhere with a single attribute.
  • Group related tests into hierarchies using Swift’s type system.
  • Integrate seamlessly with Swift concurrency.
  • Parameterize test functions across wide ranges of inputs.
  • Enable tests dynamically depending on runtime conditions.
  • Parallelize tests in-process.
  • Categorize tests using tags.
  • Associate bugs directly with the tests that verify their fixes or reproduce their problems.

XCTest vs Swift Testing

Type XCTest Swift Testing
Import import XCTest import Testing Example
Test suite class ExampleTests: XCTestCase struct ExampleTests Example
Setup and teardown class ExampleTests: XCTestCase struct ExampleTests Example
Test method @Test func example() func testExample() Example

Import

XCTest

import XCTest
@testable import Example

Swift Testing

import Testing
@testable import Example

Test suite

XCTest

class ExampleTests: XCTestCase { ... }

Swift Testing

struct ExampleTests { ... }
// or
final class ExampleTests { ... }

Setup and teardown

XCTest

class ExampleTests: XCTestCase {
  var foo: NSNumber!

  override func setUp() async throws {
    foo = 100
  }

  override func tearDown() {
    foo = 0 
  }
}

Swift Testing

struct ExampleTests {
  var foo: NSNumber

  // setUp()
  init() async throws {
    foo = 100
  }

  // tearDown()
  deinit {
    foo = 0
  }
}

// class test suite
final class ExampleTests {
  var foo: NSNumber

  // setUp()
  init() async throws {
    foo = 100
  }

  // tearDown()
  deinit {
    foo = 0
  }
}

Test method

XCTest

class ExampleTests: XCTestCase {
  func testExample1() { ... }
  func testExample2() async { ... }
  func testExample3() throws { ... }
  func testExample4() async throws { ... }
}

Swift Testing

struct ExampleTests {
  @Test func example1() { ... }
  @Test func example2() async { ... }
  @Test func example3() throws { ... }
  @Test func example4() async throws { ... }
}