import type { ErrorSchema, ValidationData } from './types.js';
/** Merges the errors in `additionalErrorSchema` into the existing `validationData` by combining the hierarchies in the
 * two `ErrorSchema`s and then appending the error list from the `additionalErrorSchema` obtained by calling
 * `toErrorList()` on the `errors` in the `validationData`. If no `additionalErrorSchema` is passed, then
 * `validationData` is returned.
 *
 * @param validationData - The current `ValidationData` into which to merge the additional errors
 * @param [additionalErrorSchema] - The optional additional set of errors in an `ErrorSchema`
 * @param [preventDuplicates=false] - Optional flag, if true, will call `mergeObjects()` with `preventDuplicates`
 * @returns - The `validationData` with the additional errors from `additionalErrorSchema` merged into it, if provided.
 */
export default function validationDataMerge<T = any>(validationData: ValidationData<T>, additionalErrorSchema?: ErrorSchema<T>, preventDuplicates?: boolean): ValidationData<T>;