Merge pull request #1511 from kchadha/restore-costume

Restore costume

src/sprites/rendered-target.js

@@ -534,12 +534,19 @@ class RenderedTarget extends Target {
     /**
      * Delete a costume by index.
      * @param {number} index Costume index to be deleted
+     * @return {?object} The costume that was deleted or null
+     * if the index was out of bounds of the costumes list or
+     * this target only has one costume.
      */
     deleteCostume (index) {
         const originalCostumeCount = this.sprite.costumes.length;
-        if (originalCostumeCount === 1) return;
+        if (originalCostumeCount === 1) return null;
 
-        this.sprite.deleteCostumeAt(index);
+        if (index < 0 || index >= originalCostumeCount) {
+            return null;
+        }
+
+        const deletedCostume = this.sprite.deleteCostumeAt(index);
 
         if (index === this.currentCostume && index === originalCostumeCount - 1) {
             this.setCostume(index - 1);
@@ -550,6 +557,7 @@ class RenderedTarget extends Target {
         }
 
         this.runtime.requestTargetsUpdate(this);
+        return deletedCostume;
     }
 
     /**

src/sprites/sprite.js

@@ -93,11 +93,10 @@ class Sprite {
     /**
      * Delete a costume by index.
      * @param {number} index Costume index to be deleted
+     * @return {?object} The deleted costume
      */
     deleteCostumeAt (index) {
-        this.costumes_ = this.costumes_
-            .slice(0, index)
-            .concat(this.costumes_.slice(index + 1));
+        return this.costumes.splice(index, 1)[0];
     }
 
     /**

src/virtual-machine.js

@@ -589,9 +589,19 @@ class VirtualMachine extends EventEmitter {
     /**
      * Delete a costume from the current editing target.
      * @param {int} costumeIndex - the index of the costume to be removed.
+     * @return {?function} A function to restore the deleted costume, or null,
+     * if no costume was deleted.
      */
     deleteCostume (costumeIndex) {
-        this.editingTarget.deleteCostume(costumeIndex);
+        const deletedCostume = this.editingTarget.deleteCostume(costumeIndex);
+        if (deletedCostume) {
+            const target = this.editingTarget;
+            return () => {
+                target.addCostume(deletedCostume);
+                this.emitTargetsUpdate();
+            };
+        }
+        return null;
     }
 
     /**

test/unit/sprites_rendered-target.js

@@ -116,41 +116,45 @@ test('deleteCostume', t => {
     //    Costume 2   =>     Costume 3
     //    Costume 3
     a.setCostume(0);
-    a.deleteCostume(0);
+    const deletedCostume = a.deleteCostume(0);
     t.equals(a.sprite.costumes.length, 2);
     t.equals(a.sprite.costumes[0].id, 2);
     t.equals(a.sprite.costumes[1].id, 3);
     t.equals(a.currentCostume, 0);
+    t.deepEqual(deletedCostume, o1);
 
     //    Costume 1          Costume 1
     // x* Costume 2   =>   * Costume 3
     //    Costume 3
     a.sprite.costumes = [o1, o2, o3];
     a.setCostume(1);
-    a.deleteCostume(1);
+    const deletedCostume2 = a.deleteCostume(1);
     t.equals(a.sprite.costumes.length, 2);
     t.equals(a.sprite.costumes[0].id, 1);
     t.equals(a.sprite.costumes[1].id, 3);
     t.equals(a.currentCostume, 1);
+    t.deepEqual(deletedCostume2, o2);
 
     //    Costume 1          Costume 1
     //    Costume 2   =>   * Costume 2
     // x* Costume 3
     a.sprite.costumes = [o1, o2, o3];
     a.setCostume(2);
-    a.deleteCostume(2);
+    const deletedCostume3 = a.deleteCostume(2);
     t.equals(a.sprite.costumes.length, 2);
     t.equals(a.sprite.costumes[0].id, 1);
     t.equals(a.sprite.costumes[1].id, 2);
     t.equals(a.currentCostume, 1);
+    t.deepEqual(deletedCostume3, o3);
 
     // Refuses to delete only costume
     a.sprite.costumes = [o1];
     a.setCostume(0);
-    a.deleteCostume(0);
+    const noDeletedCostume = a.deleteCostume(0);
     t.equals(a.sprite.costumes.length, 1);
     t.equals(a.sprite.costumes[0].id, 1);
     t.equals(a.currentCostume, 0);
+    t.equal(noDeletedCostume, null);
 
     //   Costume 1          Costume 1
     // x Costume 2          Costume 3

test/unit/virtual-machine.js

@@ -30,6 +30,30 @@ test('deleteSound returns function after deleting or null if nothing was deleted
     t.end();
 });
 
+test('deleteCostume returns function after deleting or null if nothing was deleted', t => {
+    const vm = new VirtualMachine();
+    const sprite = new Sprite();
+    sprite.costumes = [{id: 1}, {id: 2}, {id: 3}];
+    sprite.currentCostume = 0;
+    const rt = new Runtime();
+    const target = new RenderedTarget(sprite, rt);
+    vm.editingTarget = target;
+
+    const addFun = vm.deleteCostume(1);
+    t.equal(sprite.costumes.length, 2);
+    t.equal(sprite.costumes[0].id, 1);
+    t.equal(sprite.costumes[1].id, 3);
+    t.type(addFun, 'function');
+
+    const noAddFun = vm.deleteCostume(2);
+    t.equal(sprite.costumes.length, 2);
+    t.equal(sprite.costumes[0].id, 1);
+    t.equal(sprite.costumes[1].id, 3);
+    t.equal(noAddFun, null);
+
+    t.end();
+});
+
 
 test('addSprite throws on invalid string', t => {
     const vm = new VirtualMachine();