Address Copilot review: guards, bounds clear, DOM listener cleanup

- Container: clear bounds before child aggregation for infinite containers
- ImageLayer: throw if parentApp unavailable in onActivateEvent
- Input: throw if Application not initialized when enabling pointer events
- Application: store DOM event handlers, remove them in destroy()
- TMXTileMap: move app resolution inside setViewportBounds branch

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: obiot

packages/melonjs/src/application/application.ts

@@ -155,6 +155,11 @@ export default class Application {
 
 	// min update step size
 	stepSize: number;
+
+	// DOM event handlers (stored for cleanup in destroy)
+	private _onResize?: (e: Event) => void;
+	private _onOrientationChange?: (e: Event) => void;
+	private _onScroll?: (e: Event) => void;
 	updateDelta: number;
 	lastUpdateStart: number | null;
 	updateAverageDelta: number;
@@ -313,20 +318,16 @@ export default class Application {
 		setDefaultGame(this);
 
 		// bridge DOM events to the melonJS event system
-		globalThis.addEventListener("resize", (e) => {
-			emit(WINDOW_ONRESIZE, e);
-		});
-		globalThis.addEventListener("orientationchange", (e) => {
+		this._onResize = (e: Event) => emit(WINDOW_ONRESIZE, e);
+		this._onOrientationChange = (e: Event) =>
 			emit(WINDOW_ONORIENTATION_CHANGE, e);
-		});
+		this._onScroll = (e: Event) => emit(WINDOW_ONSCROLL, e);
+		globalThis.addEventListener("resize", this._onResize);
+		globalThis.addEventListener("orientationchange", this._onOrientationChange);
 		if (device.screenOrientation) {
-			globalThis.screen.orientation.onchange = (e) => {
-				emit(WINDOW_ONORIENTATION_CHANGE, e);
-			};
+			globalThis.screen.orientation.onchange = this._onOrientationChange;
 		}
-		globalThis.addEventListener("scroll", (e) => {
-			emit(WINDOW_ONSCROLL, e);
-		});
+		globalThis.addEventListener("scroll", this._onScroll);
 
 		// react to resize/orientation changes
 		on(WINDOW_ONRESIZE, () => {
@@ -516,6 +517,19 @@ export default class Application {
 		off(STAGE_RESET, this.reset, this);
 		/* eslint-enable @typescript-eslint/unbound-method */
 
+		// remove DOM event listeners
+		if (this._onResize) {
+			globalThis.removeEventListener("resize", this._onResize);
+			globalThis.removeEventListener(
+				"orientationchange",
+				this._onOrientationChange!,
+			);
+			globalThis.removeEventListener("scroll", this._onScroll!);
+			if (device.screenOrientation) {
+				globalThis.screen.orientation.onchange = null;
+			}
+		}
+
 		// destroy the world and all its children
 		if (this.world) {
 			this.world.destroy();

packages/melonjs/src/input/pointerevent.ts

@@ -138,6 +138,9 @@ function registerEventListener(
  */
 function enablePointerEvent(): void {
 	if (!pointerInitialized) {
+		if (!_app) {
+			throw new Error("Pointer events require an initialized Application");
+		}
 		// the current pointer area
 		currentPointer = new Rect(0, 0, 1, 1);
 

packages/melonjs/src/level/tiled/TMXTileMap.js

@@ -413,26 +413,26 @@ export default class TMXTileMap {
 		 * callback funtion for the viewport resize event
 		 * @ignore
 		 */
-		const app = container.getRootAncestor().app;
-
-		function _setBounds(width, height) {
-			// adjust the viewport bounds if level is smaller
-			app.viewport.setBounds(
-				0,
-				0,
-				Math.max(levelBounds.width, width),
-				Math.max(levelBounds.height, height),
-			);
-			// center the map if smaller than the current viewport
-			container.pos.set(
-				Math.max(0, ~~((width - levelBounds.width) / 2)),
-				Math.max(0, ~~((height - levelBounds.height) / 2)),
-				// don't change the container z position if defined
-				container.pos.z,
-			);
-		}
-
 		if (setViewportBounds === true) {
+			const app = container.getRootAncestor().app;
+
+			function _setBounds(width, height) {
+				// adjust the viewport bounds if level is smaller
+				app.viewport.setBounds(
+					0,
+					0,
+					Math.max(levelBounds.width, width),
+					Math.max(levelBounds.height, height),
+				);
+				// center the map if smaller than the current viewport
+				container.pos.set(
+					Math.max(0, ~~((width - levelBounds.width) / 2)),
+					Math.max(0, ~~((height - levelBounds.height) / 2)),
+					// don't change the container z position if defined
+					container.pos.z,
+				);
+			}
+
 			off(VIEWPORT_ONRESIZE, _setBounds);
 			// force viewport bounds update
 			_setBounds(app.viewport.width, app.viewport.height);

packages/melonjs/src/renderable/container.js

@@ -570,6 +570,9 @@ export default class Container extends Renderable {
 		if (this.isFinite()) {
 			// call parent method only when container has finite dimensions
 			super.updateBounds(absolute);
+		} else if (this.enableChildBoundsUpdate === true) {
+			// clear bounds so child aggregation starts fresh
+			bounds.clear();
 		}
 
 		if (this.enableChildBoundsUpdate === true) {

packages/melonjs/src/renderable/imagelayer.js

@@ -123,6 +123,11 @@ export default class ImageLayer extends Sprite {
 
 	// called when the layer is added to the game world or a container
 	onActivateEvent() {
+		if (!this.parentApp) {
+			throw new Error(
+				"ImageLayer requires a parent Application (must be added to an app's world container)",
+			);
+		}
 		const viewport = this.parentApp.viewport;
 		// set the initial size to match the viewport
 		this.resize(viewport.width, viewport.height);