New tests: scrollTo and autoslide

test/utils/scroll-to.test.js

@@ -0,0 +1,23 @@
+jest.useFakeTimers();
+
+beforeAll(() => {
+  const brs = '<br />'.repeat(20);
+  document.body.innerHTML = `<div id="webslides">${brs}</div>`;
+});
+
+test('ScrollTo utility', () => {
+  const ws = document.getElementById('webslides');
+  // Needs to be required and not imported because const defined in top level
+  const scrollTo = require('../../src/js/utils/scroll-to');
+  const cb = jest.fn();
+
+  scrollTo.default(100, 500, cb);
+
+  expect(cb).not.toBeCalled();
+  expect(ws.scrollTop).toBe(0);
+
+  jest.runAllTimers();
+
+  expect(cb).toBeCalled();
+  expect(ws.scrollTop).toBe(100);
+});