SwiftUI Snapshot Testing

A Swift package that provides snapshot testing capabilities for SwiftUI views on both iOS and macOS platforms. This package extends the functionality of swift-snapshot-testing to make it easier to test cross platform SwiftUI views.

• For pure SwiftUI views use assertRender(view: view). This uses the ImageRenderer API.
• For UIKit/AppKit based SwiftUI views, use assertSnapshot(view: view).
• To wait for view tasks, use try #require(await expression { model.loaded })

Requirements

• iOS 16.0+ / macOS 15.0+
• Swift 6.0+

Installation

Swift Package Manager

Add the following to your Package.swift file:

dependencies: [
    .package(url: "https://github.com/gabriel/swiftui-snapshot-testing", from: "0.1.1")
]

.testTarget(
    dependencies: [
        .product(name: "SwiftUISnapshotTesting", package: "swiftui-snapshot-testing"),
    ]
)

Testing SwiftUI Views

import SwiftUI
import SwiftUISnapshotTesting
import Testing

// To test pure SwiftUI view, use assertRender (which uses ImageRenderer).
@Test @MainActor
func testMyViewRender() throws {
    let view = MyView()
    // All platforms with specific size
    assertRender(view: view, device: .size(400, 400))

    // iOS with size
    assertRender(view: view, device: .iOS(width: 400, height: 1000))
    // macOS with size
    assertRender(view: view, device: .macOS(width: 1200, height: 800))
    // All platforms with default size
    assertRender(view: view, device: .any)
}

// To test SwiftUI views that wrap UIKit, you can't use assertRender, so use assertSnapshot.
@Test @MainActor
func testMyViewSnapshot() throws {
    let view = NavigationStack {
        MyView()
    }    
    // All platforms with specific size
    assertSnapshot(view: view, device: .size(400, 400))

    // iOS with size
    assertSnapshot(view: view, device: .iOS(width: 400, height: 1000))
    // macOS with size
    assertSnapshot(view: view, device: .macOS(width: 1200, height: 800))
    // All platforms with default size
    assertSnapshot(view: view, device: .any)
}

Testing with Async Tasks

@Test
func testAsyncTask() async throws {
  let model = await MyViewModel()
  let view = MyView(model: model)

  // Loading
  await assertRender(view: view, device: .any)
 
  // Wait for model load
  try #require(await expression { model.loaded })

  // Loaded
  await assertRender(view: view, device: .any)
}

Features

• Support for both iOS and macOS platforms, via swift test and xcodebuild test.
• Async expectation/wait for View tasks.

License

This project is licensed under the MIT License - see the LICENSE file for details.

Contributing

Contributions are welcome! Please feel free to submit a Pull Request.

Test

swift test

xcodebuild test -scheme SwiftUISnapshotTesting -destination 'platform=iOS Simulator,name=iPhone 16,OS=18.5'
# Or
swift test --ios # With zsh plugin below

ZSH plugin for swift test --ios

mkdir -p ~/.oh-my-zsh/custom/plugins/swift-ios-test
cp swift-ios-test.plugin.zsh ~/.oh-my-zsh/custom/plugins/swift-ios-test/swift-ios-test.plugin.zsh

# Add swift-ios-test to .zshrc
# plugins=(git swift-ios-test ...)

source ~/.zshrc

Then..

swift test --ios