Method reducer

src/queryCore/core/query.ts:561–636

(
    state: QueryState<TData, TError>,
    action: Action<TData, TError>
  )

  }

  protected reducer(
    state: QueryState<TData, TError>,
    action: Action<TData, TError>
  ): QueryState<TData, TError> {
    switch (action.type) {
      case 'failed':
        return {
          ...state,
          fetchFailureCount: state.fetchFailureCount + 1,
        }
      case 'pause':
        return {
          ...state,
          isPaused: true,
        }
      case 'continue':
        return {
          ...state,
          isPaused: false,
        }
      case 'fetch':
        return {
          ...state,
          fetchFailureCount: 0,
          fetchMeta: action.meta ?? null,
          isFetching: true,
          isPaused: false,
          ...(!state.dataUpdatedAt && {
            error: null,
            status: 'loading',
          }),
        }
      case 'success':
        return {
          ...state,
          data: action.data,
          dataUpdateCount: state.dataUpdateCount + 1,
          dataUpdatedAt: action.dataUpdatedAt ?? Date.now(),
          error: null,
          fetchFailureCount: 0,
          isFetching: false,
          isInvalidated: false,
          isPaused: false,
          status: 'success',
        }
      case 'error':
        const error = action.error as unknown

        if (isCancelledError(error) && error.revert && this.revertState) {
          return { ...this.revertState }
        }

        return {
          ...state,
          error: error as TError,
          errorUpdateCount: state.errorUpdateCount + 1,
          errorUpdatedAt: Date.now(),
          fetchFailureCount: state.fetchFailureCount + 1,