function expectStyleEquals(style, expected) {
  expect(style).to.be.a(Style);

  const gotFill = style.getFill();
  const expectedFill = expected.getFill();
  if (expectedFill) {
    expectFillEquals(gotFill, expectedFill);
  } else {
    expect(gotFill).to.be(null);
  }

  const gotStroke = style.getStroke();
  const expectedStroke = expected.getStroke();
  if (expectedStroke) {
    expectStrokeEquals(gotStroke, expectedStroke);
  } else {
    expect(gotStroke).to.be(null);
  }

  const gotImage = style.getImage();
  const expectedImage = expected.getImage();
  if (expectedImage) {
    expectImageEquals(gotImage, expectedImage);
  } else {
    expect(gotImage).to.be(null);
  }
}
@param {Style} style The style to test.
@param {Style} expected The expected style.