Class TQuery_

packages/core/src/render3/queries/query.ts:173–318

}

class TQuery_ implements TQuery {
  matches: number[] | null = null;
  indexInDeclarationView = -1;
  crossesNgTemplate = false;

  /**
   * A node index on which a query was declared (-1 for view queries and ones inherited from the
   * declaration template). We use this index (alongside with _appliesToNextNode flag) to know
   * when to apply content queries to elements in a template.
   */
  private _declarationNodeIndex: number;

  /**
   * A flag indicating if a given query still applies to nodes it is crossing. We use this flag
   * (alongside with _declarationNodeIndex) to know when to stop applying content queries to
   * elements in a template.
   */
  private _appliesToNextNode = true;

  constructor(
    public metadata: TQueryMetadata,
    nodeIndex: number = -1,
  ) {
    this._declarationNodeIndex = nodeIndex;
  }

  elementStart(tView: TView, tNode: TNode): void {
    if (this.isApplyingToNode(tNode)) {
      this.matchTNode(tView, tNode);
    }
  }

  elementEnd(tNode: TNode): void {
    if (this._declarationNodeIndex === tNode.index) {
      this._appliesToNextNode = false;
    }
  }

  template(tView: TView, tNode: TNode): void {
    this.elementStart(tView, tNode);
  }

  embeddedTView(tNode: TNode, childQueryIndex: number): TQuery | null {
    if (this.isApplyingToNode(tNode)) {
      this.crossesNgTemplate = true;
      // A marker indicating a `<ng-template>` element (a placeholder for query results from
      // embedded views created based on this `<ng-template>`).
      this.addMatch(-tNode.index, childQueryIndex);
      return new TQuery_(this.metadata);
    }
    return null;
  }

  private isApplyingToNode(tNode: TNode): boolean {
    if (
      this._appliesToNextNode &&
      (this.metadata.flags & QueryFlags.descendants) !== QueryFlags.descendants
    ) {