fix: guard accessibility updates behind window != nil

BlueprintUIAccessibilityCore/Sources/AccessibilityComposition.swift

@@ -407,6 +407,7 @@ extension AccessibilityComposition {
         }
 
         private func updateAccessibility() {
+            guard window != nil else { return }
             let sorting = customSorting ?? Accessibility.frameSort(
                 direction: layoutDirection,
                 root: self,
@@ -438,6 +439,7 @@ extension AccessibilityComposition.CombinableView {
 
     public override var isAccessibilityElement: Bool {
         get {
+            guard window != nil else { return false }
             if needsAccessibilityUpdate {
                 updateAccessibility()
             }
@@ -486,6 +488,16 @@ extension AccessibilityComposition.CombinableView {
         set { super.accessibilityIdentifier = newValue }
     }
 
+    public override var accessibilityTraits: UIAccessibilityTraits {
+        get {
+            if needsAccessibilityUpdate {
+                updateAccessibility()
+            }
+            return super.accessibilityTraits
+        }
+        set { super.accessibilityTraits = newValue }
+    }
+
     public override var accessibilityElements: [Any]? {
         get {
             if needsAccessibilityUpdate {

BlueprintUIAccessibilityCore/Sources/AccessibilityDeferral.swift

@@ -271,8 +271,6 @@ extension AccessibilityDeferral {
         public func backingViewDescription(with context: BlueprintUI.ViewDescriptionContext) -> BlueprintUI.ViewDescription? {
             ReceiverContainerView.describe { config in
                 config.apply { view in
-                    view.isAccessibilityElement = true
-                    view.needsAccessibilityUpdate = true
                     view.layoutDirection = context.environment.layoutDirection
                     view.element = wrappedElement
                 }
@@ -291,7 +289,6 @@ extension AccessibilityDeferral {
 
             override init(frame: CGRect) {
                 super.init(frame: frame)
-                isAccessibilityElement = true
                 mergeInteractiveSingleChild = false
 
                 blueprintView.backgroundColor = .clear
@@ -302,6 +299,14 @@ extension AccessibilityDeferral {
                 fatalError("init(coder:) has not been implemented")
             }
 
+            override func didMoveToWindow() {
+                super.didMoveToWindow()
+                isAccessibilityElement = (window != nil)
+                if window != nil {
+                    needsAccessibilityUpdate = true
+                }
+            }
+
             override func layoutSubviews() {
                 super.layoutSubviews()
                 blueprintView.frame = bounds
@@ -335,6 +340,7 @@ extension AccessibilityDeferral {
             }
 
             public func updateDeferredAccessibility(frameProvider: FrameProvider?) {
+                guard window != nil else { return }
                 needsAccessibilityUpdate = true
 
                 self.frameProvider = frameProvider
@@ -420,6 +426,7 @@ extension AccessibilityDeferral {
         }
 
         private func updateAccessibility() {
+            guard window != nil else { return }
             needsAccessibilityUpdate = false
             blueprintView.layoutIfNeeded()
             let elements = blueprintView.recursiveAccessibleElements()

BlueprintUIAccessibilityCore/Tests/AccessibilityCompositionTests.swift

@@ -331,7 +331,9 @@
     }
 
     func test_blockWhenNotAccessible_givenPopulatedAccessibility() {
+        let window = UIWindow()
         let view = AccessibilityComposition.CombinableView()
+        window.addSubview(view)
         view.blockWhenNotAccessible = true
         (1...3)
             .map { int in
@@ -358,7 +360,9 @@
     }
 
     func test_blockWhenNotAccessible_givenEmptyAccessibility() {
+        let window = UIWindow()
         let view = AccessibilityComposition.CombinableView()
+        window.addSubview(view)
         view.blockWhenNotAccessible = true
         (1...3)
             .map { int in
@@ -384,6 +388,39 @@
         XCTAssertFalse(view.isAccessibilityElement, "The view should not be accessible.")
     }
 
+    func test_updateAccessibility_skipsWhenNotInWindow() {
+        let view = AccessibilityComposition.CombinableView()
+        view.blockWhenNotAccessible = true
+        let subview = UIView()
+        subview.isAccessibilityElement = true
+        subview.accessibilityLabel = "Should not appear"
+        view.addSubview(subview)
+
+        view.setNeedsLayout()
+        view.layoutIfNeeded()
+
+        XCTAssertNil(view.accessibilityLabel)
+        XCTAssertTrue(view.needsAccessibilityUpdate)
+    }
+
+    func test_updateAccessibility_runsAfterMovingToWindow() {
+        let view = AccessibilityComposition.CombinableView()
+        view.blockWhenNotAccessible = true
+        let subview = UIView()
+        subview.isAccessibilityElement = true
+        subview.accessibilityLabel = "Now visible"
+        view.addSubview(subview)
+
+        view.setNeedsLayout()
+        view.layoutIfNeeded()
+        XCTAssertNil(view.accessibilityLabel)
+        XCTAssertTrue(view.needsAccessibilityUpdate)
+
+        let window = UIWindow()
+        window.addSubview(view)
+        XCTAssertEqual(view.accessibilityLabel, "Now visible")
+        XCTAssertFalse(view.needsAccessibilityUpdate)
+    }
 
     func test_applyAccessibility() {