Function warnIfNotHydrating

docs/index.js:22758–22763

()

          (idStack[idStackIndex] = null);
    }
    function warnIfNotHydrating() {
      isHydrating ||
        console.error(
          "Expected to be hydrating. This is a bug in React. Please file an issue."
        );
    }
    function buildHydrationDiffNode(fiber, distanceFromLeaf) {
      if (null === fiber.return) {
        if (null === hydrationDiffRootDEV)