Undo a cancelled ReanimatedDrawerLayout pan

packages/react-native-gesture-handler/src/__tests__/reanimatedDrawerLayoutRelease.test.tsx

@@ -0,0 +1,208 @@
+import { act, render } from '@testing-library/react-native';
+import React from 'react';
+import { Text } from 'react-native';
+import type { SharedValue } from 'react-native-reanimated';
+
+import GestureHandlerRootView from '../components/GestureHandlerRootView';
+import type { DrawerLayoutMethods } from '../components/ReanimatedDrawerLayout';
+import ReanimatedDrawerLayout, {
+  DrawerState,
+} from '../components/ReanimatedDrawerLayout';
+import { createGestureController } from '../jestUtils';
+import type * as Gestures from '../v3/hooks/gestures';
+
+let mockLastPanGesture: Gestures.PanGesture | undefined;
+
+jest.mock('../v3/hooks/gestures', () => {
+  const actual = jest.requireActual<typeof Gestures>('../v3/hooks/gestures');
+
+  return {
+    ...actual,
+    usePanGesture: jest.fn(
+      (...args: Parameters<typeof actual.usePanGesture>) => {
+        mockLastPanGesture = actual.usePanGesture(...args);
+        return mockLastPanGesture;
+      }
+    ),
+  };
+});
+
+jest.mock('react-native-reanimated', () => {
+  // eslint-disable-next-line @typescript-eslint/no-unsafe-assignment
+  const ReactNative = jest.requireActual('react-native');
+  // eslint-disable-next-line @typescript-eslint/no-unsafe-assignment
+  const ReactActual = jest.requireActual('react');
+  // eslint-disable-next-line @typescript-eslint/no-unsafe-member-access
+  const AnimatedView: unknown = ReactNative.View;
+
+  // Piecewise linear, clamped at both ends.
+  const interpolate = (value: number, input: number[], output: number[]) => {
+    if (value <= input[0]) {
+      return output[0];
+    }
+
+    for (let i = 1; i < input.length; i++) {
+      if (value <= input[i]) {
+        const progress = (value - input[i - 1]) / (input[i] - input[i - 1]);
+        return output[i - 1] + progress * (output[i] - output[i - 1]);
+      }
+    }
+
+    return output[output.length - 1];
+  };
+
+  const runUpdater = (updater: () => unknown) => updater();
+  const noEventHandler = () => undefined;
+
+  return {
+    __esModule: true,
+    default: {
+      View: AnimatedView,
+      createAnimatedComponent: (component: unknown) => component,
+    },
+    View: AnimatedView,
+    createAnimatedComponent: (component: unknown) => component,
+    Extrapolation: { CLAMP: 'clamp' },
+    interpolate,
+    isSharedValue: () => false,
+    useAnimatedProps: runUpdater,
+    useAnimatedStyle: runUpdater,
+    useComposedEventHandler: noEventHandler,
+    useDerivedValue: runUpdater,
+    useSharedValue: (init: unknown) => {
+      // eslint-disable-next-line @typescript-eslint/no-unsafe-assignment, @typescript-eslint/no-unsafe-call, @typescript-eslint/no-unsafe-member-access
+      const ref = ReactActual.useRef({ value: init });
+      // eslint-disable-next-line @typescript-eslint/no-unsafe-return, @typescript-eslint/no-unsafe-member-access
+      return ref.current;
+    },
+    withSpring: jest.fn(
+      (
+        to: unknown,
+        _config: unknown,
+        callback?: (finished: boolean) => void
+      ) => {
+        callback?.(true);
+        return to;
+      }
+    ),
+  };
+});
+
+jest.mock('react-native-worklets', () =>
+  jest.requireActual<Record<string, unknown>>('react-native-worklets/src/mock')
+);
+
+async function flushScheduledCallbacks() {
+  await act(async () => {
+    await new Promise<void>((resolve) => {
+      setTimeout(resolve, 0);
+    });
+  });
+}
+
+const DRAWER_WIDTH = 200;
+
+describe('ReanimatedDrawerLayout pan release', () => {
+  const callbacks = {
+    onDrawerOpen: jest.fn(),
+    onDrawerClose: jest.fn(),
+    onDrawerStateChanged: jest.fn(),
+  };
+
+  function renderDrawer() {
+    const drawerRef = React.createRef<DrawerLayoutMethods>();
+    let progress: SharedValue<number> | undefined;
+
+    render(
+      <GestureHandlerRootView>
+        <ReanimatedDrawerLayout
+          ref={drawerRef}
+          drawerWidth={DRAWER_WIDTH}
+          renderNavigationView={(value) => {
+            progress = value;
+            return <Text>Drawer</Text>;
+          }}
+          {...callbacks}>
+          <Text>Content</Text>
+        </ReanimatedDrawerLayout>
+      </GestureHandlerRootView>
+    );
+
+    if (!mockLastPanGesture || !progress) {
+      throw new Error('ReanimatedDrawerLayout did not render');
+    }
+
+    return {
+      pan: createGestureController(mockLastPanGesture),
+      drawerRef,
+      progress: () => progress?.value,
+    };
+  }
+
+  function clearCallbacks() {
+    Object.values(callbacks).forEach((callback) => callback.mockClear());
+  }
+
+  beforeEach(() => {
+    jest.clearAllMocks();
+  });
+
+  test('opens the drawer when the pan ends past half of its width', async () => {
+    const { pan, progress } = renderDrawer();
+
+    pan.begin({ x: 10 });
+    pan.activate({ x: 13, translationX: 3 });
+    pan.update({ x: 160, translationX: 150 });
+    pan.end({ x: 160, translationX: 150, velocityX: 0 });
+    await flushScheduledCallbacks();
+
+    expect(callbacks.onDrawerOpen).toHaveBeenCalledTimes(1);
+    expect(callbacks.onDrawerClose).not.toHaveBeenCalled();
+    expect(progress()).toBe(1);
+  });
+
+  test.each(['cancel', 'fail'] as const)(
+    'keeps a closed drawer closed when the pan is %sed past half of its width',
+    async (action) => {
+      const { pan, progress } = renderDrawer();
+
+      pan.begin({ x: 10 });
+      pan.activate({ x: 13, translationX: 3 });
+      pan.update({ x: 160, translationX: 150 });
+      pan[action]({ x: 160, translationX: 150, velocityX: 0 });
+      await flushScheduledCallbacks();
+
+      expect(callbacks.onDrawerOpen).not.toHaveBeenCalled();
+      expect(callbacks.onDrawerStateChanged).toHaveBeenLastCalledWith(
+        DrawerState.IDLE,
+        false
+      );
+      expect(progress()).toBe(0);
+    }
+  );
+
+  test.each(['cancel', 'fail'] as const)(
+    'keeps an open drawer open when the pan is %sed past half of its width',
+    async (action) => {
+      const { pan, drawerRef, progress } = renderDrawer();
+
+      drawerRef.current?.openDrawer();
+      await flushScheduledCallbacks();
+      expect(progress()).toBe(1);
+      clearCallbacks();
+
+      pan.begin({ x: 190 });
+      pan.activate({ x: 187, translationX: -3 });
+      pan.update({ x: 40, translationX: -150 });
+      pan[action]({ x: 40, translationX: -150, velocityX: 0 });
+      await flushScheduledCallbacks();
+
+      expect(callbacks.onDrawerClose).not.toHaveBeenCalled();
+      expect(callbacks.onDrawerStateChanged).toHaveBeenLastCalledWith(
+        DrawerState.IDLE,
+        true
+      );
+      expect(progress()).toBe(1);
+    }
+  );
+});

packages/react-native-gesture-handler/src/components/ReanimatedDrawerLayout.tsx

@@ -454,8 +454,14 @@ const DrawerLayout = function DrawerLayout(
   );
 
   const handleRelease = useCallback(
-    (event: PanGestureActiveEvent) => {
+    (event: PanGestureActiveEvent & { canceled: boolean }) => {
       'worklet';
+      if (event.canceled) {
+        // Settle the drawer where it rested before the gesture.
+        animateDrawer(isDrawerOpen.value ? drawerWidth : 0, 0);
+        return;
+      }
+
       let { translationX: dragX, velocityX, x: touchX } = event;
 
       if (drawerPosition !== DrawerPosition.LEFT) {