Function collectEnvInjectors

packages/core/src/debug/ai/di_graph.ts:157–206

* Collects and serializes all environment injectors found in the hierarchy of the given * `rootLViews`. * * Injectors have pointers to their parents, but not their children, so walking "down" the * hierarchy is not a generally supported operation. * * The function walks down the `LView` hierar

(rootLViews: LView[])

 *     injector tree.
 */
function collectEnvInjectors(rootLViews: LView[]): SerializedInjector {
  const serializedEnvInjectorMap = new Map<Injector, SerializedInjector>();
  let rootEnvInjector: SerializedInjector | undefined = undefined;

  /**
   * Serialize all the ancestors of the given injector and return
   * its serialized version.
   *
   * @param injector The environment injector to start from.
   * @returns The serialized form of the input {@link Injector}.
   */
  function serializeAncestors(injector: Injector): SerializedInjector {
    const existing = serializedEnvInjectorMap.get(injector);
    if (existing) return existing;

    const serialized = serializeInjector(injector);
    serializedEnvInjectorMap.set(injector, serialized);

    const parentInjector = getParentEnvInjector(injector);
    if (parentInjector) {
      // Recursively process the parent and attach ourselves as a child.
      const parentSerialized = serializeAncestors(parentInjector);
      parentSerialized.children.push(serialized);
    } else {
      // If there is no parent, this is a root environment injector.
      if (!rootEnvInjector) {
        rootEnvInjector = serialized;
      } else if (rootEnvInjector !== serialized) {
        throw new Error('Expected only one root environment injector, but found multiple.', {
          cause: {firstRoot: rootEnvInjector, secondRoot: serialized},
        });
      }
    }

    return serialized;
  }

  // Process all descendant environment injectors.
  for (const rootLView of rootLViews) {
    for (const [, lView] of walkLViewDirectives(rootLView)) {
      serializeAncestors(lView[INJECTOR]);
    }
  }

  if (!rootEnvInjector) {
    throw new Error('Expected a root environment injector but did not find one.');
  }

  return rootEnvInjector;
}

/**
 * Checks if `node` is a descendant of `ancestor` within the SAME view.