@mui/base/useDropdown/dropdownReducer.js

MUI Base is a library of headless ('unstyled') React components and low-level hooks. You gain complete control over your app's CSS and accessibility features.

import { DropdownActionTypes } from "./useDropdown.types.js";
export function dropdownReducer(state, action) {
  switch (action.type) {
    case DropdownActionTypes.blur:
      return {
        open: false,
        changeReason: action.event
      };
    case DropdownActionTypes.escapeKeyDown:
      return {
        open: false,
        changeReason: action.event
      };
    case DropdownActionTypes.toggle:
      return {
        open: !state.open,
        changeReason: action.event
      };
    case DropdownActionTypes.open:
      return {
        open: true,
        changeReason: action.event
      };
    case DropdownActionTypes.close:
      return {
        open: false,
        changeReason: action.event
      };
    default:
      throw new Error(`Unhandled action`);
  }
}