Merge pull request #1468 from gnarf/serialization-util

export deserializeBlocks method

src/serialization/sb3.js

@@ -18,6 +18,8 @@ const {loadCostume} = require('../import/load-costume.js');
 const {loadSound} = require('../import/load-sound.js');
 const {deserializeCostume, deserializeSound} = require('./deserialize-assets.js');
 
+const hasOwnProperty = Object.prototype.hasOwnProperty;
+
 /**
  * @typedef {object} ImportedProject
  * @property {Array.<Target>} targets - the imported Scratch 3.0 target objects.
@@ -99,7 +101,7 @@ const primitiveOpcodeInfoMap = {
 const serializePrimitiveBlock = function (block) {
     // Returns an array represeting a primitive block or null if not one of
     // the primitive types above
-    if (primitiveOpcodeInfoMap.hasOwnProperty(block.opcode)) {
+    if (hasOwnProperty.call(primitiveOpcodeInfoMap, block.opcode)) {
         const primitiveInfo = primitiveOpcodeInfoMap[block.opcode];
         const primitiveConstant = primitiveInfo[0];
         const fieldName = primitiveInfo[1];
@@ -132,7 +134,7 @@ const serializePrimitiveBlock = function (block) {
 const serializeInputs = function (inputs) {
     const obj = Object.create(null);
     for (const inputName in inputs) {
-        if (!inputs.hasOwnProperty(inputName)) continue;
+        if (!hasOwnProperty.call(inputs, inputName)) continue;
         // if block and shadow refer to the same block, only serialize one
         if (inputs[inputName].block === inputs[inputName].shadow) {
             // has block and shadow, and they are the same
@@ -166,7 +168,7 @@ const serializeInputs = function (inputs) {
 const serializeFields = function (fields) {
     const obj = Object.create(null);
     for (const fieldName in fields) {
-        if (!fields.hasOwnProperty(fieldName)) continue;
+        if (!hasOwnProperty.call(fields, fieldName)) continue;
         obj[fieldName] = [fields[fieldName].value];
         if (fields[fieldName].hasOwnProperty('id')) {
             obj[fieldName].push(fields[fieldName].id);
@@ -688,8 +690,10 @@ const deserializeInputs = function (inputs, parentId, blocks) {
     // because we call prototype functions later in the vm
     const obj = {};
     for (const inputName in inputs) {
-        if (!inputs.hasOwnProperty(inputName)) continue;
+        if (!hasOwnProperty.call(inputs, inputName)) continue;
         const inputDescArr = inputs[inputName];
+        // If this block has already been deserialized (it's not an array) skip it
+        if (!Array.isArray(inputDescArr)) continue;
         let block = null;
         let shadow = null;
         const blockShadowInfo = inputDescArr[0];
@@ -721,8 +725,10 @@ const deserializeFields = function (fields) {
     // because we call prototype functions later in the vm
     const obj = {};
     for (const fieldName in fields) {
-        if (!fields.hasOwnProperty(fieldName)) continue;
+        if (!hasOwnProperty.call(fields, fieldName)) continue;
         const fieldDescArr = fields[fieldName];
+        // If this block has already been deserialized (it's not an array) skip it
+        if (!Array.isArray(fieldDescArr)) continue;
         obj[fieldName] = {
             name: fieldName,
             value: fieldDescArr[0]
@@ -741,6 +747,37 @@ const deserializeFields = function (fields) {
     return obj;
 };
 
+/**
+ * Covnert serialized INPUT and FIELD primitives back to hydrated block templates.
+ * Should be able to deserialize a format that has already been deserialized.  The only
+ * "east" path to adding new targets/code requires going through deserialize, so it should
+ * work with pre-parsed deserialized blocks.
+ *
+ * @param {object} blocks Serialized SB3 "blocks" property of a target. Will be mutated.
+ * @return {object} input is modified and returned
+ */
+const deserializeBlocks = function (blocks) {
+    for (const blockId in blocks) {
+        if (!Object.prototype.hasOwnProperty.call(blocks, blockId)) {
+            continue;
+        }
+        const block = blocks[blockId];
+        if (Array.isArray(block)) {
+            // this is one of the primitives
+            // delete the old entry in object.blocks and replace it w/the
+            // deserialized object
+            delete block[blockId];
+            deserializeInputDesc(block, null, false, blocks);
+            continue;
+        }
+        block.id = blockId; // add id back to block since it wasn't serialized
+        block.inputs = deserializeInputs(block.inputs, blockId, blocks);
+        block.fields = deserializeFields(block.fields);
+    }
+    return blocks;
+};
+
+
 /**
  * Parse a single "Scratch object" and create all its in-memory VM objects.
  * @param {!object} object From-JSON "Scratch object:" sprite, stage, watcher.
@@ -766,25 +803,7 @@ const parseScratchObject = function (object, runtime, extensions, zip) {
         sprite.name = object.name;
     }
     if (object.hasOwnProperty('blocks')) {
-        for (const blockId in object.blocks) {
+        deserializeBlocks(object.blocks);
-            if (!object.blocks.hasOwnProperty(blockId)) continue;
-            const blockJSON = object.blocks[blockId];
-            if (Array.isArray(blockJSON)) {
-                // this is one of the primitives
-                // delete the old entry in object.blocks and replace it w/the
-                // deserialized object
-                delete object.blocks[blockId];
-                deserializeInputDesc(blockJSON, null, false, object.blocks);
-                continue;
-            }
-            blockJSON.id = blockId; // add id back to block since it wasn't serialized
-            const serializedInputs = blockJSON.inputs;
-            const deserializedInputs = deserializeInputs(serializedInputs, blockId, object.blocks);
-            blockJSON.inputs = deserializedInputs;
-            const serializedFields = blockJSON.fields;
-            const deserializedFields = deserializeFields(serializedFields);
-            blockJSON.fields = deserializedFields;
-        }
         // Take a second pass to create objects and add extensions
         for (const blockId in object.blocks) {
             if (!object.blocks.hasOwnProperty(blockId)) continue;
@@ -1008,5 +1027,7 @@ const deserialize = function (json, runtime, zip, isSingleSprite) {
 
 module.exports = {
     serialize: serialize,
-    deserialize: deserialize
+    deserialize: deserialize,
+    deserializeBlocks: deserializeBlocks,
+    serializeBlocks: serializeBlocks
 };

test/unit/serialization_sb3.js

@@ -182,3 +182,42 @@ test('serialize sb3 preserves sprite layer order', t => {
             t.end();
         });
 });
+
+test('serializeBlocks', t => {
+    const vm = new VirtualMachine();
+    vm.loadProject(readFileToBuffer(commentsSB3ProjectPath))
+        .then(() => {
+            const blocks = vm.runtime.targets[1].blocks._blocks;
+            const result = sb3.serializeBlocks(blocks);
+            // @todo Analyze
+            t.type(result[0], 'object');
+            t.ok(Object.keys(result[0]).length < Object.keys(blocks).length, 'less blocks in serialized format');
+            t.ok(Array.isArray(result[1]));
+            t.end();
+        });
+});
+
+test('deserializeBlocks', t => {
+    const vm = new VirtualMachine();
+    vm.loadProject(readFileToBuffer(commentsSB3ProjectPath))
+        .then(() => {
+            const blocks = vm.runtime.targets[1].blocks._blocks;
+            const serialized = sb3.serializeBlocks(blocks)[0];
+            const deserialized = sb3.deserializeBlocks(serialized);
+            t.equal(Object.keys(deserialized).length, Object.keys(blocks).length, 'same number of blocks');
+            t.end();
+        });
+});
+
+test('deserializeBlocks on already deserialized input', t => {
+    const vm = new VirtualMachine();
+    vm.loadProject(readFileToBuffer(commentsSB3ProjectPath))
+        .then(() => {
+            const blocks = vm.runtime.targets[1].blocks._blocks;
+            const serialized = sb3.serializeBlocks(blocks)[0];
+            const deserialized = sb3.deserializeBlocks(serialized);
+            const deserializedAgain = sb3.deserializeBlocks(deserialized);
+            t.deepEqual(deserialized, deserializedAgain, 'no change from second pass of deserialize');
+            t.end();
+        });
+});