Function createQueries

packages/svelte-query/src/createQueries.ts:189–264

(
  {
    queries,
    ...options
  }: {
    queries:
      | StoreOrVal<[...QueriesOptions<T>]>
      | StoreOrVal<
          [...{ [K in keyof T]: GetQueryObserverOptionsForCreateQueries<T[K]> }]
        >
    combine?: (result: QueriesResults<T>) => TCombinedResult
  },
  queryClient?: QueryClient,
)

        : { [K in keyof T]: GetCreateQueryResult<T[K]> }

export function createQueries<
  T extends Array<any>,
  TCombinedResult = QueriesResults<T>,
>(
  {
    queries,
    ...options
  }: {
    queries:
      | StoreOrVal<[...QueriesOptions<T>]>
      | StoreOrVal<
          [...{ [K in keyof T]: GetQueryObserverOptionsForCreateQueries<T[K]> }]
        >
    combine?: (result: QueriesResults<T>) => TCombinedResult
  },
  queryClient?: QueryClient,
): Readable<TCombinedResult> {
  const client = useQueryClient(queryClient)
  const isRestoring = useIsRestoring()

  const queriesStore = isSvelteStore(queries) ? queries : readable(queries)

  const defaultedQueriesStore = derived(
    [queriesStore, isRestoring],
    ([$queries, $isRestoring]) => {
      return $queries.map((opts) => {
        const defaultedOptions = client.defaultQueryOptions(
          opts as QueryObserverOptions,
        )
        // Make sure the results are already in fetching state before subscribing or updating options
        defaultedOptions._optimisticResults = $isRestoring
          ? 'isRestoring'
          : 'optimistic'
        return defaultedOptions
      })
    },
  )
  const observer = new QueriesObserver<TCombinedResult>(
    client,
    get(defaultedQueriesStore),
    options as QueriesObserverOptions<TCombinedResult>,
  )

  defaultedQueriesStore.subscribe(($defaultedQueries) => {
    // Do not notify on updates because of changes in the options because
    // these changes should already be reflected in the optimistic result.
    observer.setQueries(
      $defaultedQueries,
      options as QueriesObserverOptions<TCombinedResult>,
    )
  })

  const result = derived([isRestoring], ([$isRestoring], set) => {
    const unsubscribe = $isRestoring
      ? noop
      : observer.subscribe(notifyManager.batchCalls(set))

    return () => unsubscribe()