A11y default snapshot handling

Package.swift

@@ -17,14 +17,16 @@ let package = Package(
     ],
     dependencies: [
         .package(name: "swift-snapshot-testing", url: "https://github.com/pointfreeco/swift-snapshot-testing.git", .upToNextMajor(from: "1.12.0")),
-        .package(name: "SwiftRex", url: "https://github.com/SwiftRex/SwiftRex.git", .upToNextMajor(from: "0.8.12"))
+        .package(name: "SwiftRex", url: "https://github.com/SwiftRex/SwiftRex.git", .upToNextMajor(from: "0.8.12")),
+        .package(name: "AccessibilitySnapshot", url: "https://github.com/cashapp/AccessibilitySnapshot.git", from: "0.7.0"),
     ],
     targets: [
         .target(
             name: "TestingExtensions",
             dependencies: [
                 .product(name: "SnapshotTesting", package: "swift-snapshot-testing"),
-                .product(name: "CombineRexDynamic", package: "SwiftRex")
+                .product(name: "CombineRexDynamic", package: "SwiftRex"),
+                .product(name: "AccessibilitySnapshot", package: "AccessibilitySnapshot")
             ]
         )
     ]

Sources/TestingExtensions/SnapshotTestBase.swift

@@ -11,6 +11,20 @@ import Foundation
 import SnapshotTesting
 import SwiftUI
 import XCTest
+import AccessibilitySnapshot
+
+extension SnapshotTestBase {
+    public typealias DeviceConfiguration = (name: String, device: ViewImageConfig)
+}
+
+extension SnapshotTestBase {
+    /// Configuration of Accessibility snapshots.
+    public enum A11ySnapshotConfiguration {
+        case disabled
+        case enabled
+        case enabledWithDevices([DeviceConfiguration])
+    }
+}
 
 open class SnapshotTestBase: XCTestCase {
     public var allowAnimations: Bool = false
@@ -20,18 +34,36 @@ open class SnapshotTestBase: XCTestCase {
         UIView.setAnimationsEnabled(allowAnimations)
     }
 
-    open var defaultDevices: [(name: String, device: ViewImageConfig)] {
+    open var defaultDevices: [DeviceConfiguration] {
         [
             ("iPhone8", .iPhone8),
             ("iPhone13proMax", .iPhone13ProMax),
             ("iPadMini", .iPadMini(.portrait) ),
             ("iPadPro", .iPadPro12_9(.portrait))
         ]
     }
-
+
+    open var a11yDefaultDevices: [DeviceConfiguration] {
+        [
+            ("iPhone13pro", .iPhone13)
+        ]
+    }
+
+    /// Asserts snapshots on the given devices (or default) respecting it's parameters.
+    /// - Parameters:
+    ///   - view: The view to be snapshotted
+    ///   - devices: Specified devices, if not given it'll take default devices
+    ///   - a11ySnapshotConfiguration: Accessibility snapshot configuration, if enabled it adds a accessibility snapshot
+    ///   - style: `UIUserInterfaceStyle` to be applied
+    ///   - imageDiffPrecision: Precision of the compared images, 1 means it matches 100%, range is between 0 and 1.
+    ///   - file: The file this was executed from, it will be taken as the snapshot's file name.
+    ///   - testName: The test name taken as a part of the snapshot's file name.
+    ///   - line: The line number on which failure occurred. Defaults to the line number on which this
+    ///     function was called.
     open func assertSnapshotDevices<V: View>(
         _ view: V,
-        devices: [(name: String, device: ViewImageConfig)]? = nil,
+        devices: [DeviceConfiguration]? = nil,
+        a11ySnapshotConfiguration: A11ySnapshotConfiguration = .disabled,
         style:  [UIUserInterfaceStyle] = [.unspecified],
         imageDiffPrecision: Float = 1.0,
         file: StaticString = #file,
@@ -43,18 +75,19 @@ open class SnapshotTestBase: XCTestCase {
                 let vc = UIHostingController(rootView: view)
                 vc.overrideUserInterfaceStyle = uiStyle
 
-                let suffix: String
-                switch uiStyle {
-                case .unspecified:
-                    suffix = ""
-                case .light:
-                    suffix = "-light"
-                case .dark:
-                    suffix = "-dark"
-                @unknown default:
-                    fatalError("Unhandled UIUserInterfaceStyle \(uiStyle)")
-                }
-
+                let suffix: String = {
+                    switch uiStyle {
+                    case .unspecified:
+                        return ""
+                    case .light:
+                        return "-light"
+                    case .dark:
+                        return "-dark"
+                    @unknown default:
+                        fatalError("Unhandled UIUserInterfaceStyle \(uiStyle)")
+                    }
+                }()
+
                 assertSnapshot(
                     of: vc,
                     as: .image(on: config.device, precision: imageDiffPrecision),
@@ -64,6 +97,33 @@ open class SnapshotTestBase: XCTestCase {
                 )
             }
         }
+
+        let a11ySnapshotDevices: [DeviceConfiguration]? = {
+            switch a11ySnapshotConfiguration {
+            case .disabled:
+                return nil
+            case .enabled:
+                return a11yDefaultDevices
+            case .enabledWithDevices(let specifiedDevices):
+                return specifiedDevices
+            }
+        }()
+
+        guard let a11ySnapshotDevices else { return }
+
+        guard UIApplication.shared != nil else {
+            XCTFail("Accessibility snapshots must be run from a hosting application!")
+        }
+
+        a11ySnapshotDevices.forEach { config in
+            assertSnapshot(
+                of: view,
+                as: .accessibilityImage(showActivationPoints: .always, drawHierarchyInKeyWindow: true),
+                file: file,
+                testName: "\(testName)-\(config.name)-accessibility",
+                line: line
+            )
+        }
     }
 }
 #endif