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-gui/test/unit/util/drag-recognizer.test.js

@@ -0,0 +1,120 @@
+import DragRecognizer from '../../../src/lib/drag-recognizer';
+
+describe('DragRecognizer', () => {
+    let onDrag;
+    let onDragEnd;
+    let dragRecognizer;
+
+    beforeEach(() => {
+        onDrag = jest.fn();
+        onDragEnd = jest.fn();
+        dragRecognizer = new DragRecognizer({onDrag, onDragEnd});
+    });
+
+    afterEach(() => {
+        dragRecognizer.reset();
+    });
+
+    test('start -> small drag', () => {
+        dragRecognizer.start({clientX: 100, clientY: 100});
+        window.dispatchEvent(new MouseEvent('mousemove', {clientX: 101, clientY: 101}));
+        expect(onDrag).not.toHaveBeenCalled();
+    });
+
+    test('start -> large vertical touch move -> scroll, not drag', () => {
+        dragRecognizer.start({clientX: 100, clientY: 100});
+        window.dispatchEvent(new MouseEvent('touchmove', {clientX: 106, clientY: 150}));
+        expect(onDrag).not.toHaveBeenCalled();
+    });
+
+    test('start -> large vertical mouse move -> mouse moves always drag)', () => {
+        dragRecognizer.start({clientX: 100, clientY: 100});
+        window.dispatchEvent(new MouseEvent('mousemove', {clientX: 100, clientY: 150}));
+        expect(onDrag).toHaveBeenCalled();
+    });
+
+    test('start -> large horizontal touch move -> drag', () => {
+        dragRecognizer.start({clientX: 100, clientY: 100});
+        window.dispatchEvent(new MouseEvent('touchmove', {clientX: 150, clientY: 106}));
+        expect(onDrag).toHaveBeenCalled();
+    });
+
+    test('after starting a scroll, it cannot become a drag', () => {
+        dragRecognizer.start({clientX: 100, clientY: 100});
+        window.dispatchEvent(new MouseEvent('touchmove', {clientX: 100, clientY: 110}));
+        window.dispatchEvent(new MouseEvent('touchmove', {clientX: 100, clientY: 100}));
+        window.dispatchEvent(new MouseEvent('touchmove', {clientX: 110, clientY: 100}));
+        expect(onDrag).not.toHaveBeenCalled();
+    });
+
+    test('start -> end unbinds', () => {
+        dragRecognizer.start({clientX: 100, clientY: 100});
+        window.dispatchEvent(new MouseEvent('touchmove', {clientX: 150, clientY: 106}));
+        expect(onDrag).toHaveBeenCalledTimes(1);
+        window.dispatchEvent(new MouseEvent('touchend', {clientX: 150, clientY: 106}));
+        window.dispatchEvent(new MouseEvent('touchmove', {clientX: 150, clientY: 106}));
+        expect(onDrag).toHaveBeenCalledTimes(1); // Still 1
+    });
+
+    test('start -> end calls dragEnd callback after resetting internal state', done => {
+        onDragEnd = () => {
+            expect(dragRecognizer.gestureInProgress()).toBe(false);
+            done();
+        };
+        dragRecognizer = new DragRecognizer({onDrag, onDragEnd});
+        dragRecognizer.start({clientX: 100, clientY: 100});
+        window.dispatchEvent(new MouseEvent('touchmove', {clientX: 150, clientY: 106}));
+        window.dispatchEvent(new MouseEvent('touchend', {clientX: 150, clientY: 106}));
+    });
+
+    test('start -> reset unbinds', () => {
+        dragRecognizer.start({clientX: 100, clientY: 100});
+        window.dispatchEvent(new MouseEvent('touchmove', {clientX: 150, clientY: 106}));
+        expect(onDrag).toHaveBeenCalledTimes(1);
+        dragRecognizer.reset();
+        window.dispatchEvent(new MouseEvent('touchmove', {clientX: 150, clientY: 106}));
+        expect(onDrag).toHaveBeenCalledTimes(1); // Still 1
+    });
+
+    test('scrolls do not call prevent default', () => {
+        dragRecognizer.start({clientX: 100, clientY: 100});
+        const event = new MouseEvent('touchmove', {clientX: 100, clientY: 110});
+        event.preventDefault = jest.fn();
+        window.dispatchEvent(event);
+        expect(event.preventDefault).toHaveBeenCalledTimes(0);
+    });
+
+    test('confirmed drags have preventDefault called on them', () => {
+        dragRecognizer.start({clientX: 100, clientY: 100});
+        const event = new MouseEvent('touchmove', {clientX: 150, clientY: 106});
+        event.preventDefault = jest.fn();
+        window.dispatchEvent(event);
+        expect(event.preventDefault).toHaveBeenCalled();
+    });
+
+    test('multiple horizontal drag angles', () => {
+        // +45 from horizontal => drag
+        dragRecognizer.start({clientX: 0, clientY: 0});
+        window.dispatchEvent(new MouseEvent('touchmove', {clientX: 10, clientY: 10}));
+        expect(onDrag).toHaveBeenCalledTimes(1);
+        dragRecognizer.reset();
+
+        // -45 from horizontal => drag
+        dragRecognizer.start({clientX: 0, clientY: 0});
+        window.dispatchEvent(new MouseEvent('touchmove', {clientX: 10, clientY: -10}));
+        expect(onDrag).toHaveBeenCalledTimes(2);
+        dragRecognizer.reset();
+
+        // +135 from horizontal => drag
+        dragRecognizer.start({clientX: 0, clientY: 0});
+        window.dispatchEvent(new MouseEvent('touchmove', {clientX: -10, clientY: 10}));
+        expect(onDrag).toHaveBeenCalledTimes(3);
+        dragRecognizer.reset();
+
+        // -135 from horizontal => drag
+        dragRecognizer.start({clientX: 0, clientY: 0});
+        window.dispatchEvent(new MouseEvent('touchmove', {clientX: -10, clientY: -10}));
+        expect(onDrag).toHaveBeenCalledTimes(4);
+        dragRecognizer.reset();
+    });
+});