qlik-oss/sn-table

import { renderHook } from "@testing-library/react";
import { VariableSizeList } from "react-window";
import { ViewService } from "../../../../types";
import { BodyRef } from "../../types";
import useScrollHandler from "../use-scroll-handler";

describe("useScrollHandler", () => {
  let headerRef: React.RefObject<VariableSizeList<any>>;
  let bodyRef: React.RefObject<BodyRef>;
  let totalsRef: React.RefObject<VariableSizeList<any>>;
  let listInstance: VariableSizeList;
  let listTotalsInstance: VariableSizeList;
  let refHandler: BodyRef;
  let viewService: ViewService;

  beforeEach(() => {
    listInstance = { scrollTo: () => {} } as unknown as VariableSizeList;
    listTotalsInstance = { scrollTo: () => {} } as unknown as VariableSizeList;
    refHandler = { interpolatedScrollTo: () => {}, resizeCells: () => {} } as BodyRef;

    headerRef = { current: listInstance };
    totalsRef = { current: listTotalsInstance };
    bodyRef = { current: refHandler };
    viewService = { qTop: 0, qHeight: 1, scrollLeft: 0, estimatedRowHeight: 25 };
  });

  afterEach(() => {
    jest.restoreAllMocks();
  });

  test("should scroll body, header and totals", () => {
    const headerScrollToSpy = jest.spyOn(listInstance, "scrollTo");
    const totalsScrollToSpy = jest.spyOn(listTotalsInstance, "scrollTo");
    const bodyScrollToSpy = jest.spyOn(refHandler, "interpolatedScrollTo");

    const { result } = renderHook(() => useScrollHandler(headerRef, totalsRef, bodyRef, viewService));

    const event = {
      currentTarget: { scrollLeft: 1, scrollTop: 5, scrollHeight: 20, clientHeight: 10 },
    } as unknown as React.SyntheticEvent;

    result.current(event);

    expect(headerScrollToSpy).toHaveBeenCalledWith(event.currentTarget.scrollLeft);
    expect(totalsScrollToSpy).toHaveBeenCalledWith(event.currentTarget.scrollLeft);
    expect(bodyScrollToSpy).toHaveBeenCalledWith(0.5, event.currentTarget.scrollLeft);
  });
});