Function updateReducer

docs/external/js/react-dom.development.js:15172–15297

(reducer, initialArg, init)

  }

  function updateReducer(reducer, initialArg, init) {
    var hook = updateWorkInProgressHook();
    var queue = hook.queue;

    if (!(queue !== null)) {
      {
        throw Error( "Should have a queue. This is likely a bug in React. Please file an issue." );
      }
    }

    queue.lastRenderedReducer = reducer;
    var current = currentHook; // The last rebase update that is NOT part of the base state.

    var baseQueue = current.baseQueue; // The last pending update that hasn't been processed yet.

    var pendingQueue = queue.pending;

    if (pendingQueue !== null) {
      // We have new updates that haven't been processed yet.
      // We'll add them to the base queue.
      if (baseQueue !== null) {
        // Merge the pending queue and the base queue.
        var baseFirst = baseQueue.next;
        var pendingFirst = pendingQueue.next;
        baseQueue.next = pendingFirst;
        pendingQueue.next = baseFirst;
      }

      current.baseQueue = baseQueue = pendingQueue;
      queue.pending = null;
    }

    if (baseQueue !== null) {
      // We have a queue to process.
      var first = baseQueue.next;
      var newState = current.baseState;
      var newBaseState = null;
      var newBaseQueueFirst = null;
      var newBaseQueueLast = null;
      var update = first;

      do {
        var updateExpirationTime = update.expirationTime;

        if (updateExpirationTime < renderExpirationTime) {
          // Priority is insufficient. Skip this update. If this is the first
          // skipped update, the previous update/state is the new base
          // update/state.
          var clone = {
            expirationTime: update.expirationTime,
            suspenseConfig: update.suspenseConfig,
            action: update.action,
            eagerReducer: update.eagerReducer,
            eagerState: update.eagerState,
            next: null
          };

          if (newBaseQueueLast === null) {