Initial commit of 001code-html Scratch frontend project.

Includes scratch-gui, scratch-vm, scratch-blocks, scratch-render, scratch-l10n, and deployment config.

Co-authored-by: Cursor <cursoragent@cursor.com>

scratch-vm/test/unit/util_timer.js

@@ -0,0 +1,64 @@
+const test = require('tap').test;
+const Timer = require('../../src/util/timer');
+
+// Stubbed current time
+let NOW = 0;
+
+const testNow = {
+    now: () => {
+        NOW += 100;
+        return NOW;
+    }
+};
+
+test('spec', t => {
+    const timer = new Timer(testNow);
+
+    t.type(Timer, 'function');
+    t.type(timer, 'object');
+
+    t.type(timer.startTime, 'number');
+    t.type(timer.time, 'function');
+    t.type(timer.start, 'function');
+    t.type(timer.timeElapsed, 'function');
+    t.type(timer.setTimeout, 'function');
+    t.type(timer.clearTimeout, 'function');
+
+    t.end();
+});
+
+test('time', t => {
+    const timer = new Timer(testNow);
+    const time = timer.time();
+
+    t.ok(testNow.now() >= time);
+    t.end();
+});
+
+test('start / timeElapsed', t => {
+    const timer = new Timer(testNow);
+    const delay = 100;
+    const threshold = 1000 / 60; // 60 hz
+
+    // Start timer
+    timer.start();
+
+    // Measure timer
+    const timeElapsed = timer.timeElapsed();
+    t.ok(timeElapsed >= 0);
+    t.ok(timeElapsed >= (delay - threshold) &&
+         timeElapsed <= (delay + threshold));
+    t.end();
+});
+
+test('setTimeout / clearTimeout', t => new Promise((resolve, reject) => {
+    const timer = new Timer(testNow);
+    const cancelId = timer.setTimeout(() => {
+        reject(new Error('Canceled task ran'));
+    }, 1);
+    timer.setTimeout(() => {
+        resolve('Non-canceled task ran');
+        t.end();
+    }, 2);
+    timer.clearTimeout(cancelId);
+}));