Function getOrCreateNodeInjectorForNode

packages/core/src/render3/di.ts:193–228

(
  tNode: TElementNode | TContainerNode | TElementContainerNode,
  lView: LView,
)

 * @returns Node injector
 */
export function getOrCreateNodeInjectorForNode(
  tNode: TElementNode | TContainerNode | TElementContainerNode,
  lView: LView,
): number {
  const existingInjectorIndex = getInjectorIndex(tNode, lView);
  if (existingInjectorIndex !== -1) {
    return existingInjectorIndex;
  }

  const tView = lView[TVIEW];
  if (tView.firstCreatePass) {
    tNode.injectorIndex = lView.length;
    insertBloom(tView.data, tNode); // foundation for node bloom
    insertBloom(lView, null); // foundation for cumulative bloom
    insertBloom(tView.blueprint, null);
  }

  const parentLoc = getParentInjectorLocation(tNode, lView);
  const injectorIndex = tNode.injectorIndex;

  // If a parent injector can't be found, its location is set to -1.
  // In that case, we don't need to set up a cumulative bloom
  if (hasParentInjector(parentLoc)) {
    const parentIndex = getParentInjectorIndex(parentLoc);
    const parentLView = getParentInjectorView(parentLoc, lView);
    const parentData = parentLView[TVIEW].data as any;
    // Creates a cumulative bloom filter that merges the parent's bloom filter
    // and its own cumulative bloom (which contains tokens for all ancestors)
    for (let i = 0; i < NodeInjectorOffset.BLOOM_SIZE; i++) {
      lView[injectorIndex + i] = parentLView[parentIndex + i] | parentData[parentIndex + i];
    }
  }

  lView[injectorIndex + NodeInjectorOffset.PARENT] = parentLoc;
  return injectorIndex;
}

function insertBloom(arr: any[], footer: TNode | null): void {
  arr.push(0, 0, 0, 0, 0, 0, 0, 0, footer);