fix(sb3_definitions): prevent sprites from being named _stage_

add test fixture and unit test for this change

lib/sb3_definitions.json

@@ -347,7 +347,8 @@
             "description": "Description of property (and/or property/value pairs) for sprites.",
             "properties": {
                 "name": {
-                    "type": "string"
+                    "type": "string",
+                    "not": {"enum": ["_stage_"]}
                 },
                 "isStage": {
                     "type": "boolean",

test/fixtures/data.js

@@ -54,5 +54,7 @@ module.exports = {
     sprite2: sprite2,
     layerOrderSB3Json: fs.readFileSync(path.resolve(__dirname, './data/_layer_ordering.json')),
     invalidStageLayerSB3Json: fs.readFileSync(path.resolve(__dirname, './data/invalid/_invalid_stage_layer.json')),
-    invalidSpriteLayerSB3Json: fs.readFileSync(path.resolve(__dirname, './data/invalid/_invalid_sprite_layer.json'))
+    invalidSpriteLayerSB3Json: fs.readFileSync(path.resolve(__dirname, './data/invalid/_invalid_sprite_layer.json')),
+    invalidSpriteNameSB3Json: fs.readFileSync(
+        path.resolve(__dirname, './data/invalid/_invalid_spriteNamed_stage_.json'))
 };

test/fixtures/data/invalid/_invalid_spriteNamed_stage_.json

@@ -0,0 +1,103 @@
+{
+  "targets": [
+    {
+      "isStage": true,
+      "name": "Stage",
+      "variables": {
+        "`jEk@4|i[#Fk?(8x)AV.-my variable": [
+          "my variable",
+          0
+        ]
+      },
+      "lists": {},
+      "broadcasts": {},
+      "blocks": {},
+      "comments": {},
+      "currentCostume": 0,
+      "costumes": [
+        {
+          "assetId": "cd21514d0531fdffb22204e0ec5ed84a",
+          "name": "backdrop1",
+          "md5ext": "cd21514d0531fdffb22204e0ec5ed84a.svg",
+          "dataFormat": "svg",
+          "rotationCenterX": 240,
+          "rotationCenterY": 180
+        }
+      ],
+      "sounds": [
+        {
+          "assetId": "83a9787d4cb6f3b7632b4ddfebf74367",
+          "name": "pop",
+          "dataFormat": "wav",
+          "format": "",
+          "rate": 44100,
+          "sampleCount": 1032,
+          "md5ext": "83a9787d4cb6f3b7632b4ddfebf74367.wav"
+        }
+      ],
+      "volume": 100,
+      "layerOrder": 0,
+      "tempo": 60,
+      "videoTransparency": 50,
+      "videoState": "on",
+      "textToSpeechLanguage": null
+    },
+    {
+      "isStage": false,
+      "name": "_stage_",
+      "variables": {},
+      "lists": {},
+      "broadcasts": {},
+      "blocks": {},
+      "comments": {},
+      "currentCostume": 0,
+      "costumes": [
+        {
+          "assetId": "b7853f557e4426412e64bb3da6531a99",
+          "name": "costume1",
+          "bitmapResolution": 1,
+          "md5ext": "b7853f557e4426412e64bb3da6531a99.svg",
+          "dataFormat": "svg",
+          "rotationCenterX": 48,
+          "rotationCenterY": 50
+        },
+        {
+          "assetId": "e6ddc55a6ddd9cc9d84fe0b4c21e016f",
+          "name": "costume2",
+          "bitmapResolution": 1,
+          "md5ext": "e6ddc55a6ddd9cc9d84fe0b4c21e016f.svg",
+          "dataFormat": "svg",
+          "rotationCenterX": 46,
+          "rotationCenterY": 53
+        }
+      ],
+      "sounds": [
+        {
+          "assetId": "83c36d806dc92327b9e7049a565c6bff",
+          "name": "Meow",
+          "dataFormat": "wav",
+          "format": "",
+          "rate": 44100,
+          "sampleCount": 37376,
+          "md5ext": "83c36d806dc92327b9e7049a565c6bff.wav"
+        }
+      ],
+      "volume": 100,
+      "layerOrder": 1,
+      "visible": true,
+      "x": 0,
+      "y": 0,
+      "size": 100,
+      "direction": 90,
+      "draggable": false,
+      "rotationStyle": "all around"
+    }
+  ],
+  "monitors": [],
+  "extensions": [],
+  "meta": {
+    "semver": "3.0.0",
+    "vm": "0.2.0-prerelease.20181218172555",
+    "agent": "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_14_0) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/70.0.3538.110 Safari/537.36"
+  }
+}

test/unit/validate.js

@@ -97,3 +97,12 @@ test('sb3 json with invalid layerOrder prop for sprite', function (t) {
         t.end();
     });
 });
+
+// Sprites should not be named _stage_
+test('sb3 json with invalid sprite name', function (t) {
+    validate(false, JSON.parse(data.invalidSpriteNameSB3Json), function (err, res) {
+        t.type(err, 'object');
+        t.type(res, 'undefined');
+        t.end();
+    });
+});