getSelectedText

1/**
2 * Returns the currently selected text in the document, if any.
3 *
4 * @returns The selected text or an empty string.
5 */
6export function getSelectedText(): string {
7  const selection = window.getSelection();
8  return selection ? selection.toString() : '';
9}

1let container: HTMLDivElement;
2
3beforeEach(() => {
4  container = document.createElement('div');
5  container.innerHTML = '<p id="p1">Hello world</p>';
6  document.body.appendChild(container);
7});
8
9afterEach(() => {
10  window.getSelection()?.removeAllRanges();
11  document.body.removeChild(container);
12});
13
14test('returns selected text', () => {
15  const range = document.createRange();
16  const textNode = container.querySelector('#p1')?.firstChild!;
17  range.setStart(textNode, 0);
18  range.setEnd(textNode, 5); // "Hello"
19
20  const selection = window.getSelection();
21  selection?.removeAllRanges();
22  selection?.addRange(range);
23
24  expect(getSelectedText()).toBe('Hello');
25});
26
27test('returns empty string when nothing is selected', () => {
28  const selection = window.getSelection();
29  selection?.removeAllRanges();
30
31  expect(getSelectedText()).toBe('');
32});
33
34test('returns empty string when getSelection is null', () => {
35  const original = window.getSelection;
36  // @ts-expect-error simulate null selection
37  window.getSelection = () => null;
38
39  expect(getSelectedText()).toBe('');
40
41  window.getSelection = original; // restore
42});