function getValFromCacheAndUpdatedDownstreamDeps()

in packages/recoil/recoil_values/Recoil_selector.js [795:847]

• 38 lines of code
• 5 McCabe index (conditional complexity)

  function getValFromCacheAndUpdatedDownstreamDeps(
    store: Store,
    state: TreeState,
  ): ?Loadable<T> {
    const depsAfterCacheDone = new Set();
    const executionInfo = getExecutionInfo(store);

    let cachedVal;
    try {
      cachedVal = cache.get(
        nodeKey => {
          invariant(
            typeof nodeKey === 'string',
            'Cache nodeKey is type string',
          );

          const loadable = getCachedNodeLoadable(store, state, nodeKey);

          return loadable.contents;
        },
        {
          onNodeVisit: node => {
            if (node.type === 'branch' && node.nodeKey !== key) {
              depsAfterCacheDone.add(node.nodeKey);
            }
          },
        },
      );
    } catch (error) {
      throw err(
        `Problem with cache lookup for selector "${key}": ${error.message}`,
      );
    }

    /**
     * Ensure store contains correct dependencies if we hit the cache so that
     * the store deps and cache are in sync for a given state. This is important
     * because store deps are normally updated when new executions are created,
     * but cache hits don't trigger new executions but they still _may_ signifiy
     * a change in deps in the store if the store deps for this state are empty
     * or stale.
     */
    if (cachedVal) {
      setDepsInStore(
        store,
        state,
        depsAfterCacheDone,
        executionInfo?.latestExecutionId,
      );
    }

    return cachedVal;
  }