@react-navigation/core/lib/commonjs/useRouteCache.js

Core utilities for building navigators

"use strict";

Object.defineProperty(exports, "__esModule", {
  value: true
});
exports.CHILD_STATE = void 0;
exports.useRouteCache = useRouteCache;
var React = _interopRequireWildcard(require("react"));
var _isRecordEqual = require("./isRecordEqual.js");
function _getRequireWildcardCache(e) { if ("function" != typeof WeakMap) return null; var r = new WeakMap(), t = new WeakMap(); return (_getRequireWildcardCache = function (e) { return e ? t : r; })(e); }
function _interopRequireWildcard(e, r) { if (!r && e && e.__esModule) return e; if (null === e || "object" != typeof e && "function" != typeof e) return { default: e }; var t = _getRequireWildcardCache(r); if (t && t.has(e)) return t.get(e); var n = { __proto__: null }, a = Object.defineProperty && Object.getOwnPropertyDescriptor; for (var u in e) if ("default" !== u && {}.hasOwnProperty.call(e, u)) { var i = a ? Object.getOwnPropertyDescriptor(e, u) : null; i && (i.get || i.set) ? Object.defineProperty(n, u, i) : n[u] = e[u]; } return n.default = e, t && t.set(e, n), n; }
/**
 * Utilities such as `getFocusedRouteNameFromRoute` need to access state.
 * So we need a way to suppress the warning for those use cases.
 * This is fine since they are internal utilities and this is not public API.
 */
const CHILD_STATE = exports.CHILD_STATE = Symbol('CHILD_STATE');

/**
 * Hook to cache route props for each screen in the navigator.
 * This lets add warnings and modifications to the route object but keep references between renders.
 */
function useRouteCache(routes) {
  // Cache object which holds route objects for each screen
  const cache = React.useMemo(() => ({
    current: new Map()
  }), []);
  if (process.env.NODE_ENV === 'production') {
    // We don't want the overhead of creating extra maps every render in prod
    return routes;
  }
  cache.current = routes.reduce((acc, route) => {
    const previous = cache.current.get(route.key);
    const {
      state,
      ...routeWithoutState
    } = route;
    let proxy;
    if (previous && (0, _isRecordEqual.isRecordEqual)(previous, routeWithoutState)) {
      // If a cached route object already exists, reuse it
      proxy = previous;
    } else {
      proxy = routeWithoutState;
    }
    if (process.env.NODE_ENV !== 'production') {
      // FIXME: since the state is updated with mutation, the route object cannot be frozen
      // As a workaround, loop through the object and make the properties readonly
      for (const key in proxy) {
        // @ts-expect-error: this is fine since we are looping through the object
        const value = proxy[key];
        Object.defineProperty(proxy, key, {
          enumerable: true,
          configurable: true,
          writable: false,
          value
        });
      }
    }
    Object.defineProperty(proxy, CHILD_STATE, {
      enumerable: false,
      configurable: true,
      value: state
    });
    acc.set(route.key, proxy);
    return acc;
  }, new Map());
  return Array.from(cache.current.values());
}
//# sourceMappingURL=useRouteCache.js.map