Restore sound

src/sprites/rendered-target.js

@@ -585,12 +585,17 @@ class RenderedTarget extends Target {
     /**
      * Delete a sound by index.
      * @param {number} index Sound index to be deleted
+     * @return {object} The deleted sound object, or null if no sound was deleted.
      */
     deleteSound (index) {
-        this.sprite.sounds = this.sprite.sounds
-            .slice(0, index)
-            .concat(this.sprite.sounds.slice(index + 1));
+        // Make sure the sound index is not out of bounds
+        if (index < 0 || index >= this.sprite.sounds.length) {
+            return null;
+        }
+        // Delete the sound at the given index
+        const deletedSound = this.sprite.sounds.splice(index, 1)[0];
         this.runtime.requestTargetsUpdate(this);
+        return deletedSound;
     }
 
     /**

src/virtual-machine.js

@@ -675,9 +675,20 @@ class VirtualMachine extends EventEmitter {
     /**
      * Delete a sound from the current editing target.
      * @param {int} soundIndex - the index of the sound to be removed.
+     * @return {?Function} A function to restore the sound that was deleted,
+     * or null, if no sound was deleted.
      */
     deleteSound (soundIndex) {
-        this.editingTarget.deleteSound(soundIndex);
+        const target = this.editingTarget;
+        const deletedSound = this.editingTarget.deleteSound(soundIndex);
+        if (deletedSound) {
+            const restoreFun = () => {
+                target.addSound(deletedSound);
+                this.emitTargetsUpdate();
+            };
+            return restoreFun;
+        }
+        return null;
     }
 
     /**

test/unit/sprites_rendered-target.js

@@ -211,8 +211,9 @@ test('deleteSound', t => {
     const renderer = new FakeRenderer();
     a.renderer = renderer;
 
-    a.deleteSound(0);
+    const firstDeleted = a.deleteSound(0);
     t.deepEqual(a.sprite.sounds, [o2, o3]);
+    t.deepEqual(firstDeleted, o1);
 
     // Allows deleting the only sound
     a.sprite.sounds = [o1];

test/unit/virtual-machine.js

@@ -1,9 +1,35 @@
 const test = require('tap').test;
-const VirtualMachine = require('../../src/virtual-machine.js');
-const Sprite = require('../../src/sprites/sprite.js');
-const Variable = require('../../src/engine/variable.js');
+const VirtualMachine = require('../../src/virtual-machine');
+const Sprite = require('../../src/sprites/sprite');
+const Variable = require('../../src/engine/variable');
 const adapter = require('../../src/engine/adapter');
 const events = require('../fixtures/events.json');
+const Runtime = require('../../src/engine/runtime');
+const RenderedTarget = require('../../src/sprites/rendered-target');
+
+test('deleteSound returns function after deleting or null if nothing was deleted', t => {
+    const vm = new VirtualMachine();
+    const sprite = new Sprite();
+    sprite.sounds = [{id: 1}, {id: 2}, {id: 3}];
+    const rt = new Runtime();
+    const target = new RenderedTarget(sprite, rt);
+    vm.editingTarget = target;
+
+    const addFun = vm.deleteSound(1);
+    t.equal(sprite.sounds.length, 2);
+    t.equal(sprite.sounds[0].id, 1);
+    t.equal(sprite.sounds[1].id, 3);
+    t.type(addFun, 'function');
+
+    const noAddFun = vm.deleteSound(2);
+    t.equal(sprite.sounds.length, 2);
+    t.equal(sprite.sounds[0].id, 1);
+    t.equal(sprite.sounds[1].id, 3);
+    t.equal(noAddFun, null);
+
+    t.end();
+});
+
 
 test('addSprite throws on invalid string', t => {
     const vm = new VirtualMachine();