1 files changed, 43 insertions, 0 deletions
diff --git a/node_modules/rxjs/src/internal/scheduler/AnimationFrameAction.ts b/node_modules/rxjs/src/internal/scheduler/AnimationFrameAction.ts
new file mode 100644
index 0000000..502bbc7
--- /dev/null
+++ b/node_modules/rxjs/src/internal/scheduler/AnimationFrameAction.ts
@@ -0,0 +1,43 @@
+import { AsyncAction } from './AsyncAction';
+import { AnimationFrameScheduler } from './AnimationFrameScheduler';
+import { SchedulerAction } from '../types';
+import { animationFrameProvider } from './animationFrameProvider';
+import { TimerHandle } from './timerHandle';
+
+export class AnimationFrameAction<T> extends AsyncAction<T> {
+  constructor(protected scheduler: AnimationFrameScheduler, protected work: (this: SchedulerAction<T>, state?: T) => void) {
+    super(scheduler, work);
+  }
+
+  protected requestAsyncId(scheduler: AnimationFrameScheduler, id?: TimerHandle, delay: number = 0): TimerHandle {
+    // If delay is greater than 0, request as an async action.
+    if (delay !== null && delay > 0) {
+      return super.requestAsyncId(scheduler, id, delay);
+    }
+    // Push the action to the end of the scheduler queue.
+    scheduler.actions.push(this);
+    // If an animation frame has already been requested, don't request another
+    // one. If an animation frame hasn't been requested yet, request one. Return
+    // the current animation frame request id.
+    return scheduler._scheduled || (scheduler._scheduled = animationFrameProvider.requestAnimationFrame(() => scheduler.flush(undefined)));
+  }
+
+  protected recycleAsyncId(scheduler: AnimationFrameScheduler, id?: TimerHandle, delay: number = 0): TimerHandle | undefined {
+    // If delay exists and is greater than 0, or if the delay is null (the
+    // action wasn't rescheduled) but was originally scheduled as an async
+    // action, then recycle as an async action.
+    if (delay != null ? delay > 0 : this.delay > 0) {
+      return super.recycleAsyncId(scheduler, id, delay);
+    }
+    // If the scheduler queue has no remaining actions with the same async id,
+    // cancel the requested animation frame and set the scheduled flag to
+    // undefined so the next AnimationFrameAction will request its own.
+    const { actions } = scheduler;
+    if (id != null && id === scheduler._scheduled && actions[actions.length - 1]?.id !== id) {
+      animationFrameProvider.cancelAnimationFrame(id as number);
+      scheduler._scheduled = undefined;
+    }
+    // Return undefined so the action knows to request a new async id if it's rescheduled.
+    return undefined;
+  }
+}