Function lookupTokenUsingNodeInjector

packages/core/src/render3/di.ts:506–625

* Returns the value associated to the given token from the node injector. * * @param tNode The Node where the search for the injector should start * @param lView The `LView` that contains the `tNode` * @param token The token to look for * @param flags Injection flags * @param notFoundValue The

(
  tNode: TDirectiveHostNode,
  lView: LView,
  token: ProviderToken<T>,
  flags: InternalInjectFlags,
  notFoundValue?: any,
)

 * @returns the value from the injector, `null` when not found, or `notFoundValue` if provided
 */
function lookupTokenUsingNodeInjector<T>(
  tNode: TDirectiveHostNode,
  lView: LView,
  token: ProviderToken<T>,
  flags: InternalInjectFlags,
  notFoundValue?: any,
) {
  const bloomHash = bloomHashBitOrFactory(token);
  // If the ID stored here is a function, this is a special object like ElementRef or TemplateRef
  // so just call the factory function to create it.
  if (typeof bloomHash === 'function') {
    if (!enterDI(lView, tNode, flags)) {
      // Failed to enter DI, try module injector instead. If a token is injected with the @Host
      // flag, the module injector is not searched for that token in Ivy.
      return flags & InternalInjectFlags.Host
        ? notFoundValueOrThrow<T>(notFoundValue, token, flags)
        : lookupTokenUsingModuleInjector<T>(lView, token, flags, notFoundValue);
    }
    try {
      let value: unknown;

      if (ngDevMode) {
        runInInjectorProfilerContext(
          new NodeInjector(getCurrentTNode() as TElementNode, getLView()),
          token as Type<T>,
          () => {
            emitInjectorToCreateInstanceEvent(token);
            value = bloomHash(flags);
            emitInstanceCreatedByInjectorEvent(value);
          },
        );
      } else {
        value = bloomHash(flags);
      }

      if (value == null && !(flags & InternalInjectFlags.Optional)) {
        throwProviderNotFoundError(token);
      } else {
        return value;
      }
    } finally {
      leaveDI();
    }
  } else if (typeof bloomHash === 'number') {
    // A reference to the previous injector TView that was found while climbing the element
    // injector tree. This is used to know if viewProviders can be accessed on the current
    // injector.
    let previousTView: TView | null = null;
    let injectorIndex = getInjectorIndex(tNode, lView);
    let parentLocation = NO_PARENT_INJECTOR;
    let hostTElementNode: TNode | null =
      flags & InternalInjectFlags.Host ? lView[DECLARATION_COMPONENT_VIEW][T_HOST] : null;

    // If we should skip this injector, or if there is no injector on this node, start by
    // searching the parent injector.
    if (injectorIndex === -1 || flags & InternalInjectFlags.SkipSelf) {
      parentLocation =
        injectorIndex === -1