XCTBeton

XCTBeton is a module of the Beton library which contains multiple modules:

• Beton
• XCTBeton

Usage

Let’s say you have a simple performance test that measures some code. Using XCTest there is no easy, straightforward way to make assertions to the performance results.

import XCTest

class PerformanceTests: XCTestCase {
  func test_measureSum() {
    measure {
      let _ = (1..<1000).reduce(0, +)
    }
    // Performance assertions needed!
  }
}

You can turn this code into an XCTBeton test by simply changing the import. Yes, that’s it. You can now make assertions!

import XCTBeton

class PerformanceTests: XCTestCase {
  func test_measureSum() {
    measure {
      let _ = (1..<1000).reduce(0, +)
    }
    XCTAssertMetric(.clock, .timeMonotonic, .average(maximum: 0.001))
  }
}

If you want to control the type of measurements, and how many times the tests run you can do that using the same API as you would in regular XCTest.

import XCTBeton

class PerformanceTests: XCTestCase {
  func test_measureSum() {
    let options = XCTMeasureOptions()
    options.iterationCount = 100
    measure(metrics: [XCTCPUMetric(), XCTMemoryMetric()], options: options) {
      let _ = (1..<1000).reduce(0, +)
    }
    XCTAssertMetric(.cpu, .time, .average(maximum: 0.002))
    XCTAssertMetric(.cpu, .cycles, .average(maximum: 2000))
    XCTAssertMetric(.memory, .physical, .average(maximum: 20))
  }
}

Adding as a Dependency

To use the XCTBeton in a SwiftPM project, add it to the dependencies for your package and your target.

// swift-tools-version:5.5.0

import PackageDescription

let package = Package(
  name: "MyApplication",
  dependencies: [
    .package(url: "https://github.com/21GramConsulting/Beton", from: "1.0.0"),
  ],
  targets: [
    .target(name: "MyApplication", dependencies: [
      .product(name: "XCTBeton", package: "Beton"),
    ])
  ]
)