Function getTemplateIndexForState

packages/core/src/defer/utils.ts:73–94

(
  newState: DeferBlockState,
  hostLView: LView,
  tNode: TNode,
)

}

export function getTemplateIndexForState(
  newState: DeferBlockState,
  hostLView: LView,
  tNode: TNode,
): number | null {
  const tView = hostLView[TVIEW];
  const tDetails = getTDeferBlockDetails(tView, tNode);

  switch (newState) {
    case DeferBlockState.Complete:
      return tDetails.primaryTmplIndex;
    case DeferBlockState.Loading:
      return tDetails.loadingTmplIndex;
    case DeferBlockState.Error:
      return tDetails.errorTmplIndex;
    case DeferBlockState.Placeholder:
      return tDetails.placeholderTmplIndex;
    default:
      ngDevMode && throwError(`Unexpected defer block state: ${newState}`);
      return null;
  }
}

/**
 * Returns a minimum amount of time that a given state should be rendered for,