import type { InstanceAssert, InstanceSelector } from "@nanobpm/engine-testkit";
import type { TestApp } from "../boot-app.ts";
/** Assert over a single process instance, resolved from `keyOrSelector`
 *  (a bare key, `byKey(...)`, `byProcessId(...)`, or omitted for the single
 *  ACTIVE instance). */
export declare function assertThatInstance(app: TestApp, keyOrSelector?: string | InstanceSelector): InstanceAssert;