From e2f4bb9ffce2c11ce06a33d275dffbda3d18bf07 Mon Sep 17 00:00:00 2001
From: Michael Kauzmann <michael.kauzmann@colorado.edu>
Date: Fri, 30 Aug 2024 09:59:06 -0600
Subject: [PATCH] More memory leaks!,
 https://github.com/phetsims/density-buoyancy-common/issues/168

Signed-off-by: Michael Kauzmann <michael.kauzmann@colorado.edu>
---
 js/accessibility/nodes/WASDCueNode.ts | 33 +++++++++++++++++----------
 js/keyboard/KeyNode.ts                |  7 ++++--
 2 files changed, 26 insertions(+), 14 deletions(-)

diff --git a/js/accessibility/nodes/WASDCueNode.ts b/js/accessibility/nodes/WASDCueNode.ts
index 6fc544e3..2f77a2c2 100644
--- a/js/accessibility/nodes/WASDCueNode.ts
+++ b/js/accessibility/nodes/WASDCueNode.ts
@@ -41,19 +41,18 @@ const DIRECTION_ANGLES = {
 };
 
 export default class WASDCueNode extends Node {
-  protected wNode: Node;
-  protected aNode: Node;
-  protected sNode: Node;
-  protected dNode: Node;
+  protected readonly wNode: Node;
+  protected readonly aNode: Node;
+  protected readonly sNode: Node;
+  protected readonly dNode: Node;
 
   public constructor( boundsProperty: TReadOnlyProperty<Bounds2> ) {
-
     super();
 
-    this.wNode = this.createMovementKeyNode( 'up' );
-    this.aNode = this.createMovementKeyNode( 'left' );
-    this.sNode = this.createMovementKeyNode( 'down' );
-    this.dNode = this.createMovementKeyNode( 'right' );
+    this.wNode = WASDCueNode.createMovementKeyNode( 'up' );
+    this.aNode = WASDCueNode.createMovementKeyNode( 'left' );
+    this.sNode = WASDCueNode.createMovementKeyNode( 'down' );
+    this.dNode = WASDCueNode.createMovementKeyNode( 'right' );
 
     const directionKeysParent = new Node( {
       children: [
@@ -66,22 +65,31 @@ export default class WASDCueNode extends Node {
 
     this.addChild( directionKeysParent );
 
-    boundsProperty.link( bounds => {
+    const boundsListener = ( bounds: Bounds2 ) => {
 
       // place the direction cues relative to the object bounds
       this.wNode.centerBottom = bounds.getCenterTop().plusXY( 0, -KEY_SPACING );
       this.aNode.rightCenter = bounds.getLeftCenter().plusXY( -KEY_SPACING, 0 );
       this.sNode.centerTop = bounds.getCenterBottom().plusXY( 0, KEY_SPACING + SHADOW_OFFSET );
       this.dNode.leftCenter = bounds.getRightCenter().plusXY( KEY_SPACING + SHADOW_OFFSET, 0 );
+    };
+    boundsProperty.link( boundsListener );
+
+    this.disposeEmitter.addListener( () => {
+      boundsProperty.unlink( boundsListener );
+
+      this.wNode.dispose();
+      this.aNode.dispose();
+      this.sNode.dispose();
+      this.dNode.dispose();
     } );
   }
 
-
   /**
    * Create a node that looks like a keyboard letter key next to an arrow indicating the direction the balloon
    * would move if that key is pressed.
    */
-  private createMovementKeyNode( direction: 'up' | 'down' | 'left' | 'right' ): Node {
+  private static createMovementKeyNode( direction: 'up' | 'down' | 'left' | 'right' ): Node {
 
     // create the arrow icon
     const arrowShape = new Shape();
@@ -116,6 +124,7 @@ export default class WASDCueNode extends Node {
     }
 
     assert && assert( box!, `No box created for direction ${direction}` );
+    box!.disposeEmitter.addListener( () => keyIcon.dispose() );
     return box!;
   }
 }
diff --git a/js/keyboard/KeyNode.ts b/js/keyboard/KeyNode.ts
index d582b94a..96ba359b 100644
--- a/js/keyboard/KeyNode.ts
+++ b/js/keyboard/KeyNode.ts
@@ -109,7 +109,7 @@ export default class KeyNode extends Node {
       lineWidth: options.lineWidth
     } );
 
-    keyIcon.boundsProperty.link( () => {
+    const listener = () => {
 
       // scale down the size of the keyIcon passed in if it is taller than the max height of the icon
       let heightScalar = 1;
@@ -144,7 +144,8 @@ export default class KeyNode extends Node {
       backgroundShadow.setRectBounds( content.bounds.shiftedXY(
         options.xShadowOffset, options.yShadowOffset ) );
       whiteForeground.setRectBounds( content.bounds );
-    } );
+    };
+    keyIcon.boundsProperty.link( listener );
 
     // children of the icon node, including the background shadow, foreground key, and content icon
     options.children = [
@@ -157,6 +158,8 @@ export default class KeyNode extends Node {
     ];
 
     super( options );
+
+    this.disposeEmitter.addListener( () => keyIcon.boundsProperty.unlink( listener ) );
   }
 }