Fix tests involving scratch-storage

- Attach the storage module to the VM for tests which load projects or
  other assets.
- Move `import_sb2.js` from `test/unit/ into `test/integration` since it
  now depends heavily on `scratch-storage`.
- Skip loading costumes when there is no renderer.

src/import/sb2import.js

@@ -51,7 +51,9 @@ var parseScratchObject = function (object, runtime, topLevel) {
                 rotationCenterY: costumeSource.rotationCenterY,
                 skinId: null
             };
+            if (runtime.renderer) {
                 costumePromises.push(loadCostume(costumeSource.baseLayerMD5, costume, runtime));
+            }
             sprite.costumes.push(costume);
         }
     }
@@ -147,6 +149,7 @@ var parseScratchObject = function (object, runtime, topLevel) {
 
 /**
  * Load a costume's asset into memory asynchronously.
+ * Do not call this unless there is a renderer attached.
  * @param {string} md5ext - the MD5 and extension of the costume to be loaded.
  * @param {!object} costume - the Scratch costume object.
  * @property {int} skinId - the ID of the costume's render skin, once installed.
@@ -171,9 +174,7 @@ var loadCostume = function (md5ext, costume, runtime) {
 
     if (assetType === AssetType.ImageVector) {
         promise = promise.then(function (costumeAsset) {
-            if (runtime.renderer) {
             costume.skinId = runtime.renderer.createSVGSkin(costumeAsset.decodeText(), rotationCenter);
-            }
         });
     } else {
         promise = promise.then(function (costumeAsset) {

src/virtual-machine.js

@@ -171,7 +171,7 @@ VirtualMachine.prototype.downloadProjectId = function (id) {
 
 /**
  * Add a single sprite from the "Sprite2" (i.e., SB2 sprite) format.
- * @param {?string} json JSON string representing the sprite.
+ * @param {string} json JSON string representing the sprite.
  */
 VirtualMachine.prototype.addSprite2 = function (json) {
     // Select new sprite.

test/fixtures/attach-test-storage.js

@@ -0,0 +1,47 @@
+var ScratchStorage = require('scratch-storage');
+
+var ASSET_SERVER = 'https://cdn.assets.scratch.mit.edu/';
+var PROJECT_SERVER = 'https://cdn.projects.scratch.mit.edu/';
+
+/**
+ * @param {Asset} asset - calculate a URL for this asset.
+ * @returns {string} a URL to download a project file.
+ */
+var getProjectUrl = function (asset) {
+    var assetIdParts = asset.assetId.split('.');
+    var assetUrlParts = [PROJECT_SERVER, 'internalapi/project/', assetIdParts[0], '/get/'];
+    if (assetIdParts[1]) {
+        assetUrlParts.push(assetIdParts[1]);
+    }
+    return assetUrlParts.join('');
+};
+
+/**
+ * @param {Asset} asset - calculate a URL for this asset.
+ * @returns {string} a URL to download a project asset (PNG, WAV, etc.)
+ */
+var getAssetUrl = function (asset) {
+    var assetUrlParts = [
+        ASSET_SERVER,
+        'internalapi/asset/',
+        asset.assetId,
+        '.',
+        asset.assetType.runtimeFormat,
+        '/get/'
+    ];
+    return assetUrlParts.join('');
+};
+
+/**
+ * Construct a new instance of ScratchStorage, provide it with default web sources, and attach it to the provided VM.
+ * @param {VirtualMachine} vm - the VM which will own the new ScratchStorage instance.
+ */
+var attachTestStorage = function (vm) {
+    var storage = new ScratchStorage();
+    var AssetType = ScratchStorage.AssetType;
+    storage.addWebSource([AssetType.Project], getProjectUrl);
+    storage.addWebSource([AssetType.ImageVector, AssetType.ImageBitmap, AssetType.Sound], getAssetUrl);
+    vm.attachStorage(storage);
+};
+
+module.exports = attachTestStorage;

test/integration/complex.js

@@ -1,6 +1,7 @@
 var fs = require('fs');
 var path = require('path');
 var test = require('tap').test;
+var attachTestStorage = require('../fixtures/attach-test-storage');
 var extract = require('../fixtures/extract');
 var VirtualMachine = require('../../src/index');
 
@@ -12,6 +13,7 @@ var sprite = fs.readFileSync(spriteUri, 'utf8');
 
 test('complex', function (t) {
     var vm = new VirtualMachine();
+    attachTestStorage(vm);
 
     // Evaluate playground data and exit
     vm.on('playgroundData', function (e) {

test/integration/control.js

@@ -1,5 +1,6 @@
 var path = require('path');
 var test = require('tap').test;
+var attachTestStorage = require('../fixtures/attach-test-storage');
 var extract = require('../fixtures/extract');
 var VirtualMachine = require('../../src/index');
 
@@ -8,6 +9,7 @@ var project = extract(uri);
 
 test('control', function (t) {
     var vm = new VirtualMachine();
+    attachTestStorage(vm);
 
     // Evaluate playground data and exit
     vm.on('playgroundData', function (e) {

test/integration/data.js

@@ -1,5 +1,6 @@
 var path = require('path');
 var test = require('tap').test;
+var attachTestStorage = require('../fixtures/attach-test-storage');
 var extract = require('../fixtures/extract');
 var VirtualMachine = require('../../src/index');
 
@@ -8,6 +9,7 @@ var project = extract(uri);
 
 test('data', function (t) {
     var vm = new VirtualMachine();
+    attachTestStorage(vm);
 
     // Evaluate playground data and exit
     vm.on('playgroundData', function () {

test/integration/event.js

@@ -1,5 +1,6 @@
 var path = require('path');
 var test = require('tap').test;
+var attachTestStorage = require('../fixtures/attach-test-storage');
 var extract = require('../fixtures/extract');
 var VirtualMachine = require('../../src/index');
 
@@ -8,6 +9,7 @@ var project = extract(uri);
 
 test('event', function (t) {
     var vm = new VirtualMachine();
+    attachTestStorage(vm);
 
     // Evaluate playground data and exit
     vm.on('playgroundData', function (e) {

test/integration/hat-execution-order.js

@@ -1,5 +1,6 @@
 var path = require('path');
 var test = require('tap').test;
+var attachTestStorage = require('../fixtures/attach-test-storage');
 var extract = require('../fixtures/extract');
 var VirtualMachine = require('../../src/index');
 
@@ -8,6 +9,7 @@ var project = extract(projectUri);
 
 test('complex', function (t) {
     var vm = new VirtualMachine();
+    attachTestStorage(vm);
 
     // Evaluate playground data and exit
     vm.on('playgroundData', function (e) {

test/integration/import_sb2.js

@@ -1,5 +1,6 @@
 var path = require('path');
 var test = require('tap').test;
+var attachTestStorage = require('../fixtures/attach-test-storage');
 var extract = require('../fixtures/extract');
 
 var renderedTarget = require('../../src/sprites/rendered-target');
@@ -18,6 +19,7 @@ test('default', function (t) {
 
     // Create runtime instance & load SB2 into it
     var rt = new runtime();
+    attachTestStorage(rt);
     sb2(file, rt);
 
     // Test

test/integration/looks.js

@@ -1,5 +1,6 @@
 var path = require('path');
 var test = require('tap').test;
+var attachTestStorage = require('../fixtures/attach-test-storage');
 var extract = require('../fixtures/extract');
 var VirtualMachine = require('../../src/index');
 
@@ -8,6 +9,7 @@ var project = extract(uri);
 
 test('looks', function (t) {
     var vm = new VirtualMachine();
+    attachTestStorage(vm);
 
     // Evaluate playground data and exit
     vm.on('playgroundData', function (e) {

test/integration/motion.js

@@ -1,5 +1,6 @@
 var path = require('path');
 var test = require('tap').test;
+var attachTestStorage = require('../fixtures/attach-test-storage');
 var extract = require('../fixtures/extract');
 var VirtualMachine = require('../../src/index');
 
@@ -8,6 +9,7 @@ var project = extract(uri);
 
 test('motion', function (t) {
     var vm = new VirtualMachine();
+    attachTestStorage(vm);
 
     // Evaluate playground data and exit
     vm.on('playgroundData', function (e) {

test/integration/pen.js

@@ -1,5 +1,6 @@
 var path = require('path');
 var test = require('tap').test;
+var attachTestStorage = require('../fixtures/attach-test-storage');
 var extract = require('../fixtures/extract');
 var VirtualMachine = require('../../src/index');
 
@@ -8,6 +9,7 @@ var project = extract(uri);
 
 test('pen', function (t) {
     var vm = new VirtualMachine();
+    attachTestStorage(vm);
 
     // Evaluate playground data and exit
     vm.on('playgroundData', function () {

test/integration/procedure.js

@@ -1,5 +1,6 @@
 var path = require('path');
 var test = require('tap').test;
+var attachTestStorage = require('../fixtures/attach-test-storage');
 var extract = require('../fixtures/extract');
 var VirtualMachine = require('../../src/index');
 
@@ -8,6 +9,7 @@ var project = extract(uri);
 
 test('procedure', function (t) {
     var vm = new VirtualMachine();
+    attachTestStorage(vm);
 
     // Evaluate playground data and exit
     vm.on('playgroundData', function (e) {

test/integration/sensing.js

@@ -1,5 +1,6 @@
 var path = require('path');
 var test = require('tap').test;
+var attachTestStorage = require('../fixtures/attach-test-storage');
 var extract = require('../fixtures/extract');
 var VirtualMachine = require('../../src/index');
 
@@ -8,6 +9,7 @@ var project = extract(uri);
 
 test('sensing', function (t) {
     var vm = new VirtualMachine();
+    attachTestStorage(vm);
 
     // Evaluate playground data and exit
     vm.on('playgroundData', function (e) {

test/integration/sound.js

@@ -1,5 +1,6 @@
 var path = require('path');
 var test = require('tap').test;
+var attachTestStorage = require('../fixtures/attach-test-storage');
 var extract = require('../fixtures/extract');
 var VirtualMachine = require('../../src/index');
 
@@ -8,6 +9,7 @@ var project = extract(uri);
 
 test('sound', function (t) {
     var vm = new VirtualMachine();
+    attachTestStorage(vm);
 
     // Evaluate playground data and exit
     vm.on('playgroundData', function (e) {