Function walkElementInjectors

packages/core/src/debug/ai/di_graph.ts:96–140

* Traverses all directive-hosting nodes in the `rootLView` hierarchy and builds a tree of * serialized element injectors. * * This function uses `walkLViewDirectives` to visit nodes in depth-first order and a stack * to reconstruct the hierarchical tree of injectors, handling both same-view and

(rootLView: LView)

 * @returns The root {@link SerializedInjector} object.
 */
function walkElementInjectors(rootLView: LView): SerializedInjector {
  // Assert that we were given a root `LView` rather than a random component.
  // A root component actually gets two `LView` objects, the "root `LView`" with
  // `type === TViewType.Root` and then an `LView` for the component itself as a child.
  if (rootLView[TVIEW].type !== TViewType.Root) {
    throw new Error(`Expected a root LView but got type: \`${rootLView[TVIEW].type}\`.`);
  }

  // Track the injectors we're currently processing.
  const stack: Array<[TNode, LView, SerializedInjector]> = [];

  // By constraining `rootLView` to only accepting root `LView` objects, we don't have to
  // process `rootLView` itself, knowing that it won't be a component or directive.
  // We can just check its descendants.
  for (const [tNode, lView] of walkLViewDirectives(rootLView)) {
    const injector = new NodeInjector(tNode as TDirectiveHostNode, lView);
    const serialized = serializeInjector(injector);

    // Look for our nearest ancestor in the stack.
    while (stack.length > 0) {
      const [lastTNode, lastLView, lastInjector] = stack[stack.length - 1];

      const isDescendantInSameView = isTNodeDescendant(tNode, lastTNode);
      const isDescendantInDifferentView = isLViewDescendantOfTNode(lView, lastLView, lastTNode);
      if (isDescendantInSameView || isDescendantInDifferentView) {
        // This injector is a child of the current last injector in the stack.
        lastInjector.children.push(serialized);
        break;
      } else {
        stack.pop();
      }
    }

    // Future injectors might be children of this one.
    stack.push([tNode, lView, serialized]);
  }

  // Since all component/directive LViews are descendants of the root LView, the first
  // item on the stack must still remain and will be the root injector.
  if (stack.length === 0) {
    throw new Error(`Expected at least one component/directive in the root \`LView\`.`);
  }
  const [, , rootInjector] = stack[0];
  return rootInjector;
}

/**
 * Collects and serializes all environment injectors found in the hierarchy of the given