Merge pull request #552 from rschamp/feature/serialization

Add project serialization

package.json

@@ -43,7 +43,7 @@
     "scratch-audio": "^0.1.0-prerelease.0",
     "scratch-blocks": "^0.1.0-prerelease.0",
     "scratch-render": "^0.1.0-prerelease.0",
-    "scratch-storage": "^0.0.1-prerelease.0",
+    "scratch-storage": "^0.1.0",
     "script-loader": "0.7.0",
     "stats.js": "^0.17.0",
     "tap": "^10.2.0",

src/import/load-costume.js

@@ -30,7 +30,8 @@ const loadCostume = function (md5ext, costume, runtime) {
     ];
 
     let promise = runtime.storage.load(assetType, md5).then(costumeAsset => {
-        costume.url = costumeAsset.encodeDataURI();
+        costume.assetId = costumeAsset.assetId;
+        costume.assetType = assetType;
         return costumeAsset;
     });
 

src/import/load-sound.js

@@ -19,10 +19,17 @@ const loadSound = function (sound, runtime) {
     }
     const idParts = sound.md5.split('.');
     const md5 = idParts[0];
-    return runtime.storage.load(runtime.storage.AssetType.Sound, md5).then(soundAsset => {
-        sound.data = soundAsset.data;
-        return runtime.audioEngine.decodeSound(sound).then(() => sound);
-    });
+    return runtime.storage.load(runtime.storage.AssetType.Sound, md5)
+        .then(soundAsset => {
+            sound.assetId = soundAsset.assetId;
+            sound.assetType = runtime.storage.AssetType.Sound;
+            return runtime.audioEngine.decodeSound(Object.assign(
+                {},
+                sound,
+                {data: soundAsset.data}
+            ));
+        })
+        .then(() => sound);
 };
 
 module.exports = loadSound;

src/playground/index.html

@@ -53,9 +53,9 @@
             <button id="projectLoadButton">Load</button>
             <button id="createEmptyProject">New Project</button><br />
             <p>
-                <input type="button" value="Export to XML" onclick="toXml()">
+                <input type="button" value="Export to JSON" onclick="toJson()">
                 &nbsp;
-                <input type="button" value="Import from XML" onclick="fromXml()" id="import">
+                <input type="button" value="Import from JSON" onclick="fromJson()" id="import">
                 <br /><br />
                 <textarea id="importExport"></textarea>
             </p>
@@ -71,18 +71,17 @@
     <!-- Playground -->
     <script src="./playground.js"></script>
     <script>
-        function toXml() {
+        function toJson() {
             var output = document.getElementById('importExport');
-            var xml = Blockly.Xml.workspaceToDom(Scratch.workspace);
-            output.value = Blockly.Xml.domToPrettyText(xml);
+            var json = window.Scratch.vm.toJSON();
+            output.value = json;
             output.focus();
             output.select();
           }
 
-          function fromXml() {
+          function fromJson() {
             var input = document.getElementById('importExport');
-            var xml = Blockly.Xml.textToDom(input.value);
-            Blockly.Xml.domToWorkspace(Scratch.workspace, xml);
+            window.Scratch.vm.fromJSON(input.value);
           }
     </script>
 </body>

src/serialization/sb2.js

@@ -11,12 +11,12 @@ const Sprite = require('../sprites/sprite');
 const Color = require('../util/color');
 const log = require('../util/log');
 const uid = require('../util/uid');
-const specMap = require('./sb2specmap');
+const specMap = require('./sb2_specmap');
 const Variable = require('../engine/variable');
 const List = require('../engine/list');
 
-const loadCostume = require('./load-costume.js');
-const loadSound = require('./load-sound.js');
+const loadCostume = require('../import/load-costume.js');
+const loadSound = require('../import/load-sound.js');
 
 /**
  * Convert a Scratch 2.0 procedure string (e.g., "my_procedure %s %b %n")
@@ -276,14 +276,14 @@ const parseScratchObject = function (object, runtime, topLevel) {
 /**
  * Top-level handler. Parse provided JSON,
  * and process the top-level object (the stage object).
- * @param {!string} json SB2-format JSON to load.
+ * @param {!object} json SB2-format JSON to load.
  * @param {!Runtime} runtime Runtime object to load all structures into.
  * @param {boolean=} optForceSprite If set, treat as sprite (Sprite2).
  * @return {?Promise} Promise that resolves to the loaded targets when ready.
  */
 const sb2import = function (json, runtime, optForceSprite) {
     return parseScratchObject(
-        JSON.parse(json),
+        json,
         runtime,
         !optForceSprite
     );
@@ -470,4 +470,6 @@ const parseBlock = function (sb2block) {
     return activeBlock;
 };
 
-module.exports = sb2import;
+module.exports = {
+    deserialize: sb2import
+};

src/serialization/sb3.js

@@ -0,0 +1,165 @@
+/**
+ * @fileoverview
+ * Partial implementation of a SB3 serializer and deserializer. Parses provided
+ * JSON and then generates all needed scratch-vm runtime structures.
+ */
+
+const vmPackage = require('../../package.json');
+const Blocks = require('../engine/blocks');
+const Sprite = require('../sprites/sprite');
+const Variable = require('../engine/variable');
+const List = require('../engine/list');
+
+const loadCostume = require('../import/load-costume.js');
+const loadSound = require('../import/load-sound.js');
+
+/**
+ * Serializes the specified VM runtime.
+ * @param  {!Runtime} runtime VM runtime instance to be serialized.
+ * @return {object}    Serialized runtime instance.
+ */
+const serialize = function (runtime) {
+    // Fetch targets
+    const obj = Object.create(null);
+    obj.targets = runtime.targets;
+
+    // Assemble metadata
+    const meta = Object.create(null);
+    meta.semver = '3.0.0';
+    meta.vm = vmPackage.version;
+
+    // Attach full user agent string to metadata if available
+    meta.agent = null;
+    if (typeof navigator !== 'undefined') meta.agent = navigator.userAgent;
+
+    // Assemble payload and return
+    obj.meta = meta;
+    return obj;
+};
+
+/**
+ * Parse a single "Scratch object" and create all its in-memory VM objects.
+ * @param {!object} object From-JSON "Scratch object:" sprite, stage, watcher.
+ * @param {!Runtime} runtime Runtime object to load all structures into.
+ * @return {?Target} Target created (stage or sprite).
+ */
+const parseScratchObject = function (object, runtime) {
+    if (!object.hasOwnProperty('name')) {
+        // Watcher/monitor - skip this object until those are implemented in VM.
+        // @todo
+        return;
+    }
+    // Blocks container for this object.
+    const blocks = new Blocks();
+
+    // @todo: For now, load all Scratch objects (stage/sprites) as a Sprite.
+    const sprite = new Sprite(blocks, runtime);
+
+    // Sprite/stage name from JSON.
+    if (object.hasOwnProperty('name')) {
+        sprite.name = object.name;
+    }
+    if (object.hasOwnProperty('blocks')) {
+        for (let blockId in object.blocks) {
+            blocks.createBlock(object.blocks[blockId]);
+        }
+        // console.log(blocks);
+    }
+    // Costumes from JSON.
+    const costumePromises = (object.costumes || []).map(costumeSource => {
+        // @todo: Make sure all the relevant metadata is being pulled out.
+        const costume = {
+            skinId: null,
+            name: costumeSource.name,
+            bitmapResolution: costumeSource.bitmapResolution,
+            rotationCenterX: costumeSource.rotationCenterX,
+            rotationCenterY: costumeSource.rotationCenterY
+        };
+        const costumeMd5 = `${costumeSource.assetId}.${costumeSource.assetType.runtimeFormat}`;
+        return loadCostume(costumeMd5, costume, runtime);
+    });
+    // Sounds from JSON
+    const soundPromises = (object.sounds || []).map(soundSource => {
+        const sound = {
+            format: soundSource.format,
+            fileUrl: soundSource.fileUrl,
+            rate: soundSource.rate,
+            sampleCount: soundSource.sampleCount,
+            soundID: soundSource.soundID,
+            name: soundSource.name,
+            md5: soundSource.md5,
+            data: null
+        };
+        return loadSound(sound, runtime);
+    });
+    // Create the first clone, and load its run-state from JSON.
+    const target = sprite.createClone();
+    // Load target properties from JSON.
+    if (object.hasOwnProperty('variables')) {
+        for (let j = 0; j < object.variables.length; j++) {
+            const variable = object.variables[j];
+            target.variables[variable.name] = new Variable(
+                variable.name,
+                variable.value,
+                variable.isPersistent
+            );
+        }
+    }
+    if (object.hasOwnProperty('lists')) {
+        for (let k = 0; k < object.lists.length; k++) {
+            const list = object.lists[k];
+            // @todo: monitor properties.
+            target.lists[list.listName] = new List(
+                list.listName,
+                list.contents
+            );
+        }
+    }
+    if (object.hasOwnProperty('x')) {
+        target.x = object.x;
+    }
+    if (object.hasOwnProperty('y')) {
+        target.y = object.y;
+    }
+    if (object.hasOwnProperty('direction')) {
+        target.direction = object.direction;
+    }
+    if (object.hasOwnProperty('size')) {
+        target.size = object.size;
+    }
+    if (object.hasOwnProperty('visible')) {
+        target.visible = object.visible;
+    }
+    if (object.hasOwnProperty('currentCostume')) {
+        target.currentCostume = object.currentCostume;
+    }
+    if (object.hasOwnProperty('rotationStyle')) {
+        target.rotationStyle = object.rotationStyle;
+    }
+    if (object.hasOwnProperty('isStage')) {
+        target.isStage = object.isStage;
+    }
+    Promise.all(costumePromises).then(costumes => {
+        sprite.costumes = costumes;
+    });
+    Promise.all(soundPromises).then(sounds => {
+        sprite.sounds = sounds;
+    });
+    return Promise.all(costumePromises.concat(soundPromises)).then(() => target);
+};
+
+/**
+ * Deserializes the specified representation of a VM runtime and loads it into
+ * the provided runtime instance.
+ * @param  {object}  json    JSON representation of a VM runtime.
+ * @param  {Runtime} runtime Runtime instance
+ * @returns {Promise} Promise that resolves to the list of targets after the project is deserialized
+ */
+const deserialize = function (json, runtime) {
+    return Promise.all((json.targets || []).map(target => parseScratchObject(target, runtime)));
+};
+
+module.exports = {
+    serialize: serialize,
+    deserialize: deserialize
+};

src/sprites/rendered-target.js

@@ -764,11 +764,13 @@ class RenderedTarget extends Target {
         this.dragging = false;
     }
 
+
     /**
      * Serialize sprite info, used when emitting events about the sprite
-     * @returns {object} sprite data as a simple object
+     * @returns {object} Sprite data as a simple object
      */
     toJSON () {
+        const costumes = this.getCostumes();
         return {
             id: this.id,
             name: this.getName(),
@@ -778,12 +780,16 @@ class RenderedTarget extends Target {
             size: this.size,
             direction: this.direction,
             draggable: this.draggable,
-            costume: this.getCurrentCostume(),
-            costumes: this.getCostumes(),
-            sounds: this.getSounds(),
-            costumeCount: this.getCostumes().length,
+            currentCostume: this.currentCostume,
+            costume: costumes[this.currentCostume],
+            costumeCount: costumes.length,
             visible: this.visible,
-            rotationStyle: this.rotationStyle
+            rotationStyle: this.rotationStyle,
+            blocks: this.blocks._blocks,
+            variables: this.variables,
+            lists: this.lists,
+            costumes: costumes,
+            sounds: this.getSounds()
         };
     }
 

src/virtual-machine.js

@@ -2,7 +2,8 @@ const EventEmitter = require('events');
 
 const log = require('./util/log');
 const Runtime = require('./engine/runtime');
-const sb2import = require('./import/sb2import');
+const sb2 = require('./serialization/sb2');
+const sb3 = require('./serialization/sb3');
 const StringUtil = require('./util/string-util');
 
 const loadCostume = require('./import/load-costume.js');
@@ -145,22 +146,7 @@ class VirtualMachine extends EventEmitter {
      */
     loadProject (json) {
         // @todo: Handle other formats, e.g., Scratch 1.4, Scratch 3.0.
-        return sb2import(json, this.runtime).then(targets => {
-            this.clear();
-            for (let n = 0; n < targets.length; n++) {
-                if (targets[n] !== null) {
-                    this.runtime.targets.push(targets[n]);
-                    targets[n].updateAllDrawableProperties();
-                }
-            }
-        // Select the first target for editing, e.g., the first sprite.
-            this.editingTarget = this.runtime.targets[1];
-
-        // Update the VM user's knowledge of targets and blocks on the workspace.
-            this.emitTargetsUpdate();
-            this.emitWorkspaceUpdate();
-            this.runtime.setEditingTarget(this.editingTarget);
-        });
+        return this.fromJSON(json);
     }
 
     /**
@@ -180,12 +166,95 @@ class VirtualMachine extends EventEmitter {
         });
     }
 
+    /**
+     * @returns {string} Project in a Scratch 3.0 JSON representation.
+     */
+    saveProjectSb3 () {
+        // @todo: Handle other formats, e.g., Scratch 1.4, Scratch 2.0.
+        return this.toJSON();
+    }
+
+    /**
+     * Export project as a Scratch 3.0 JSON representation.
+     * @return {string} Serialized state of the runtime.
+     */
+    toJSON () {
+        return JSON.stringify(sb3.serialize(this.runtime));
+    }
+
+    /**
+     * Load a project from a Scratch JSON representation.
+     * @param {string} json JSON string representing a project.
+     * @returns {Promise} Promise that resolves after the project has loaded
+     */
+    fromJSON (json) {
+        // Clear the current runtime
+        this.clear();
+
+        // Validate & parse
+        if (typeof json !== 'string') {
+            log.error('Failed to parse project. Non-string supplied to fromJSON.');
+            return;
+        }
+        json = JSON.parse(json);
+        if (typeof json !== 'object') {
+            log.error('Failed to parse project. JSON supplied to fromJSON is not an object.');
+            return;
+        }
+
+        // Establish version, deserialize, and load into runtime
+        // @todo Support Scratch 1.4
+        // @todo This is an extremely naïve / dangerous way of determining version.
+        //       See `scratch-parser` for a more sophisticated validation
+        //       methodology that should be adapted for use here
+        let deserializer;
+        if ((typeof json.meta !== 'undefined') && (typeof json.meta.semver !== 'undefined')) {
+            deserializer = sb3;
+        } else {
+            deserializer = sb2;
+        }
+
+        return deserializer.deserialize(json, this.runtime).then(targets => {
+            this.clear();
+            for (let n = 0; n < targets.length; n++) {
+                if (targets[n] !== null) {
+                    this.runtime.targets.push(targets[n]);
+                    targets[n].updateAllDrawableProperties();
+                }
+            }
+            // Select the first target for editing, e.g., the first sprite.
+            if (this.runtime.targets.length > 1) {
+                this.editingTarget = this.runtime.targets[1];
+            } else {
+                this.editingTarget = this.runtime.targets[0];
+            }
+
+            // Update the VM user's knowledge of targets and blocks on the workspace.
+            this.emitTargetsUpdate();
+            this.emitWorkspaceUpdate();
+            this.runtime.setEditingTarget(this.editingTarget);
+        });
+    }
+
     /**
      * Add a single sprite from the "Sprite2" (i.e., SB2 sprite) format.
      * @param {string} json JSON string representing the sprite.
+     * @returns {Promise} Promise that resolves after the sprite is added
      */
     addSprite2 (json) {
-        sb2import(json, this.runtime, true).then(targets => {
+        // Validate & parse
+        if (typeof json !== 'string') {
+            log.error('Failed to parse sprite. Non-string supplied to addSprite2.');
+            return;
+        }
+        json = JSON.parse(json);
+        if (typeof json !== 'object') {
+            log.error('Failed to parse sprite. JSON supplied to addSprite2 is not an object.');
+            return;
+        }
+
+        // Select new sprite.
+        return sb2.deserialize(json, this.runtime, true).then(targets => {
             this.runtime.targets.push(targets[0]);
             this.editingTarget = targets[0];
             this.editingTarget.updateAllDrawableProperties();

test/fixtures/demo.json

@@ -0,0 +1 @@
+{"targets":[{"id":"poXv!.~0@*~j*F(Om/X5","name":"Stage","isStage":true,"x":0,"y":0,"size":100,"direction":90,"draggable":false,"currentCostume":10,"costume":{"name":"backdrop2","bitmapResolution":1,"rotationCenterX":240,"rotationCenterY":180,"skinId":7,"assetId":"7da4181ee167de7b3f5d1a91880277ff","assetType":{"contentType":"image/svg+xml","name":"ImageVector","runtimeFormat":"svg"}},"costumeCount":11,"visible":true,"rotationStyle":"all around","blocks":{"O7D.%E~TH^ULpAuHM8)@":{"id":"O7D.%E~TH^ULpAuHM8)@","opcode":"event_whenflagclicked","inputs":{},"fields":{},"next":"78+=E[P7b8!mBXMwQF`@","shadow":false,"x":138,"y":356.40000000000003,"topLevel":true,"parent":null},"78+=E[P7b8!mBXMwQF`@":{"id":"78+=E[P7b8!mBXMwQF`@","opcode":"control_forever","inputs":{"SUBSTACK":{"name":"SUBSTACK","block":"nlnk{2XqtVI*Qg,admbW","shadow":null}},"fields":{},"next":null,"shadow":false,"parent":"O7D.%E~TH^ULpAuHM8)@"},"nlnk{2XqtVI*Qg,admbW":{"id":"nlnk{2XqtVI*Qg,admbW","opcode":"looks_changeeffectby","inputs":{"EFFECT":{"name":"EFFECT","block":"*vh;qV87Q}5IP@sW=)wD","shadow":"*vh;qV87Q}5IP@sW=)wD"},"CHANGE":{"name":"CHANGE","block":"woYo[[v=PD(`R;qW{PZ%","shadow":"woYo[[v=PD(`R;qW{PZ%"}},"fields":{},"next":null,"shadow":false,"parent":"78+=E[P7b8!mBXMwQF`@"},"*vh;qV87Q}5IP@sW=)wD":{"id":"*vh;qV87Q}5IP@sW=)wD","opcode":"looks_effectmenu","inputs":{},"fields":{"EFFECT":{"name":"EFFECT","value":"color"}},"next":null,"topLevel":false,"parent":"nlnk{2XqtVI*Qg,admbW","shadow":true},"woYo[[v=PD(`R;qW{PZ%":{"id":"woYo[[v=PD(`R;qW{PZ%","opcode":"math_number","inputs":{},"fields":{"NUM":{"name":"NUM","value":1}},"next":null,"topLevel":false,"parent":"nlnk{2XqtVI*Qg,admbW","shadow":true}},"variables":{"vy":{"name":"vy","value":-3.5165000000000006,"isCloud":false},"g":{"name":"g","value":"-.5","isCloud":false},"vx":{"name":"vx","value":1.4580000000000002,"isCloud":false},"i":{"name":"i","value":3,"isCloud":false},"d1":{"name":"d1","value":0,"isCloud":false},"x":{"name":"x","value":233.9173278872492,"isCloud":false},"acceleration":{"name":"acceleration","value":"-3","isCloud":false}},"lists":{},"costumes":[{"name":"blue sky2","bitmapResolution":1,"rotationCenterX":240,"rotationCenterY":180,"skinId":0,"assetId":"7623e679b2baa2e7d48808614820844f","assetType":{"contentType":"image/svg+xml","name":"ImageVector","runtimeFormat":"svg"}},{"name":"woods","bitmapResolution":1,"rotationCenterX":240,"rotationCenterY":180,"skinId":3,"assetId":"1e0f7a4c932423b13250b5cb44928109","assetType":{"contentType":"image/svg+xml","name":"ImageVector","runtimeFormat":"svg"}},{"name":"party","bitmapResolution":1,"rotationCenterX":251,"rotationCenterY":189,"skinId":2,"assetId":"108160d0e44d1c340182e31c9dc0758a","assetType":{"contentType":"image/svg+xml","name":"ImageVector","runtimeFormat":"svg"}},{"name":"boardwalk","bitmapResolution":2,"rotationCenterX":480,"rotationCenterY":360,"skinId":6,"assetId":"de0e54cd11551566f044e7e6bc588b2c","assetType":{"contentType":"image/png","name":"ImageBitmap","runtimeFormat":"png"}},{"name":"blue sky3","bitmapResolution":1,"rotationCenterX":240,"rotationCenterY":179,"skinId":1,"assetId":"2024d59c1980e667e8f656134796e2c1","assetType":{"contentType":"image/svg+xml","name":"ImageVector","runtimeFormat":"svg"}},{"name":"underwater1","bitmapResolution":2,"rotationCenterX":480,"rotationCenterY":360,"skinId":5,"assetId":"f339c6f31b11ea71d0fb8d607cec392e","assetType":{"contentType":"image/png","name":"ImageBitmap","runtimeFormat":"png"}},{"name":"underwater2","bitmapResolution":2,"rotationCenterX":480,"rotationCenterY":360,"skinId":11,"assetId":"1517c21786d2d0edc2f3037408d850bd","assetType":{"contentType":"image/png","name":"ImageBitmap","runtimeFormat":"png"}},{"name":"stars","bitmapResolution":2,"rotationCenterX":480,"rotationCenterY":360,"skinId":4,"assetId":"e87fed9c2a968dbeae8c94617e600e8c","assetType":{"contentType":"image/png","name":"ImageBitmap","runtimeFormat":"png"}},{"name":"parking-ramp","bitmapResolution":2,"rotationCenterX":480,"rotationCenterY":360,"skinId":9,"assetId":"a7832479977c166ca0057f2a99a73305","assetType":{"contentType":"image/png","name":"ImageBitmap","runtimeFormat":"png"}},{"name":"backdrop1","bitmapResolution":2,"rotationCenterX":480,"rotationCenterY":360,"skinId":10,"assetId":"f67dc7de38bac6fbb0ab68e46352521d","assetType":{"contentType":"image/png","name":"ImageBitmap","runtimeFormat":"png"}},{"name":"backdrop2","bitmapResolution":1,"rotationCenterX":240,"rotationCenterY":180,"skinId":7,"assetId":"7da4181ee167de7b3f5d1a91880277ff","assetType":{"contentType":"image/svg+xml","name":"ImageVector","runtimeFormat":"svg"}}],"sounds":[{"name":"pop","format":"","rate":11025,"sampleCount":258,"soundID":-1,"md5":"83a9787d4cb6f3b7632b4ddfebf74367.wav","data":null,"assetId":"83a9787d4cb6f3b7632b4ddfebf74367","assetType":{"contentType":"audio/x-wav","name":"Sound","runtimeFormat":"wav"}}]},{"id":"9!d8G^[6i]k*:l[W%4;l","name":"Earth","isStage":false,"x":-10,"y":10,"size":100,"direction":90,"draggable":false,"currentCostLine truncated

test/integration/import_sb2.js

@@ -5,10 +5,10 @@ const extract = require('../fixtures/extract');
 
 const renderedTarget = require('../../src/sprites/rendered-target');
 const runtime = require('../../src/engine/runtime');
-const sb2 = require('../../src/import/sb2import');
+const sb2 = require('../../src/serialization/sb2');
 
 test('spec', t => {
-    t.type(sb2, 'function');
+    t.type(sb2.deserialize, 'function');
     t.end();
 });
 
@@ -16,13 +16,15 @@ test('default', t => {
     // Get SB2 JSON (string)
     const uri = path.resolve(__dirname, '../fixtures/default.sb2');
     const file = extract(uri);
+    const json = JSON.parse(file);
 
     // Create runtime instance & load SB2 into it
     const rt = new runtime();
     attachTestStorage(rt);
-    sb2(file, rt).then(targets => {
+    sb2.deserialize(json, rt).then(targets => {
         // Test
         t.type(file, 'string');
+        t.type(json, 'object');
         t.type(rt, 'object');
         t.type(targets, 'object');
 

test/unit/serialization_sb2.js

@@ -0,0 +1,53 @@
+const path = require('path');
+const test = require('tap').test;
+const extract = require('../fixtures/extract');
+
+const RenderedTarget = require('../../src/sprites/rendered-target');
+const Runtime = require('../../src/engine/runtime');
+const sb2 = require('../../src/serialization/sb2');
+
+test('spec', t => {
+    t.type(sb2, 'object');
+    t.type(sb2.deserialize, 'function');
+    t.end();
+});
+
+test('default', t => {
+    // Get SB2 JSON (string)
+    const uri = path.resolve(__dirname, '../fixtures/default.sb2');
+    const file = extract(uri);
+    const json = JSON.parse(file);
+
+    // Create runtime instance & load SB2 into it
+    const rt = new Runtime();
+    sb2.deserialize(json, rt).then(targets => {
+        // Test
+        t.type(file, 'string');
+        t.type(json, 'object');
+        t.type(rt, 'object');
+        t.type(targets, 'object');
+
+        t.ok(targets[0] instanceof RenderedTarget);
+        t.type(targets[0].id, 'string');
+        t.type(targets[0].blocks, 'object');
+        t.type(targets[0].variables, 'object');
+        t.type(targets[0].lists, 'object');
+
+        t.equal(targets[0].isOriginal, true);
+        t.equal(targets[0].currentCostume, 0);
+        t.equal(targets[0].isOriginal, true);
+        t.equal(targets[0].isStage, true);
+
+        t.ok(targets[1] instanceof RenderedTarget);
+        t.type(targets[1].id, 'string');
+        t.type(targets[1].blocks, 'object');
+        t.type(targets[1].variables, 'object');
+        t.type(targets[1].lists, 'object');
+
+        t.equal(targets[1].isOriginal, true);
+        t.equal(targets[1].currentCostume, 0);
+        t.equal(targets[1].isOriginal, true);
+        t.equal(targets[1].isStage, false);
+        t.end();
+    });
+});

test/unit/serialization_sb3.js

@@ -0,0 +1,22 @@
+const test = require('tap').test;
+const VirtualMachine = require('../../src/index');
+const sb3 = require('../../src/serialization/sb3');
+const demoSb3 = require('../fixtures/demo.json');
+
+test('serialize', t => {
+    const vm = new VirtualMachine();
+    vm.fromJSON(JSON.stringify(demoSb3));
+    const result = sb3.serialize(vm.runtime);
+    // @todo Analyze
+    t.type(JSON.stringify(result), 'string');
+    t.end();
+});
+
+test('deserialize', t => {
+    const vm = new VirtualMachine();
+    sb3.deserialize('', vm.runtime).then(targets => {
+        // @todo Analyize
+        t.type(targets, 'object');
+        t.end();
+    });
+});