import { LitElement } from 'lit';
import type { TemplateResult } from 'lit';
declare global {
    interface Window {
        tachometerResult: undefined | number;
    }
}
export declare class TestFixture extends LitElement {
    shouldAttachContents: boolean;
    template: TemplateResult;
    remove(): boolean;
    get root(): ShadowRoot;
    attachContents(options?: {
        awaitRender: boolean;
    }): Promise<unknown>;
    detachContents(options?: {
        awaitRender: boolean;
    }): Promise<unknown>;
    protected render(): TemplateResult<1>;
}
interface FixtureOptions {
    shouldAttachContents: boolean;
    document: Document;
    afterRender: ((root: ShadowRoot) => Promise<void>) | null;
}
export declare const fixture: (template: TemplateResult, options?: Partial<FixtureOptions>) => Promise<TestFixture>;
interface MeasureFixtureCreationOpts {
    afterRender?: (root: ShadowRoot) => Promise<unknown>;
    numRenders: number;
    renderCheck?: (root: ShadowRoot) => Promise<unknown>;
}
export declare const measureFixtureCreation: (template: TemplateResult, options?: Partial<MeasureFixtureCreationOpts>) => Promise<ShadowRoot>;
export declare const rafPromise: () => Promise<unknown>;
export declare const waitForEvent: (el: Element, ev: string) => Promise<unknown>;
export declare const ieSafeKeyboardEvent: (type: string, keycode: number) => CustomEvent<number>;
export {};