react-beautiful-dnd/src/state/middleware/drop-animation-finish.js

Beautiful, accessible drag and drop for lists with React.js

// @flow
import invariant from 'tiny-invariant';
import { completeDrop } from '../action-creators';
import type { State } from '../../types';
import type { MiddlewareStore, Action, Dispatch } from '../store-types';

export default (store: MiddlewareStore) => (next: Dispatch) => (
  action: Action,
): any => {
  if (action.type !== 'DROP_ANIMATION_FINISHED') {
    next(action);
    return;
  }

  const state: State = store.getState();
  invariant(
    state.phase === 'DROP_ANIMATING',
    'Cannot finish a drop animating when no drop is occurring',
  );
  store.dispatch(completeDrop(state.pending.result));
};