export type PartialIntersectionObserverEntry = Pick<IntersectionObserverEntry, 'target'> & Partial<Omit<IntersectionObserverEntry, 'target'>>;
/**
 * Mock-implementation of `IntersectionObserver` with ability of simulating intersections programmatically.
 * Useful for unit testing.
 */
export declare class IntersectionObserverMock implements IntersectionObserver {
    /** @inheritdoc */
    readonly root: Element | Document | null;
    /** @inheritdoc */
    readonly rootMargin: string;
    /** @inheritdoc */
    readonly thresholds: ReadonlyArray<number>;
    /** Callback. */
    protected readonly callback: IntersectionObserverCallback;
    /** Observed elements. */
    protected readonly elements: Set<Element>;
    constructor(callback: IntersectionObserverCallback, init?: IntersectionObserverInit);
    /** @inheritdoc */
    observe(target: Element): void;
    /** @inheritdoc */
    unobserve(target: Element): void;
    /** @inheritdoc */
    disconnect(): void;
    /** @inheritdoc */
    takeRecords(): IntersectionObserverEntry[];
    /**
     * Calls callback with given entries.
     * Each entry can omit all fields except `target`.
     * @param entries Entries.
     */
    simulateIntersection(entries: PartialIntersectionObserverEntry[]): void;
}