downloadBlob

1/**
2 * Triggers download of a Blob or File in the browser.
3 *
4 * @param blob - The Blob or File object to download.
5 * @param filename - The name for the downloaded file.
6 */
7export function downloadBlob(blob: Blob, filename: string): void {
8  const url = URL.createObjectURL(blob);
9  const a = document.createElement('a');
10  a.href = url;
11  a.download = filename;
12  a.style.display = 'none';
13
14  document.body.appendChild(a);
15  a.click();
16  document.body.removeChild(a);
17
18  URL.revokeObjectURL(url);
19}

1test('downloadBlob - creates anchor and triggers download', () => {
2  const blob = new Blob(['Hello, world!'], { type: 'text/plain' });
3  const mockCreateObjectURL = vi.spyOn(URL, 'createObjectURL').mockReturnValue('blob:url');
4  const mockRevokeObjectURL = vi.spyOn(URL, 'revokeObjectURL');
5
6  const appendChild = vi.spyOn(document.body, 'appendChild');
7  const removeChild = vi.spyOn(document.body, 'removeChild');
8
9  downloadBlob(blob, 'test.txt');
10
11  expect(mockCreateObjectURL).toHaveBeenCalledWith(blob);
12  expect(mockRevokeObjectURL).toHaveBeenCalledWith('blob:url');
13  expect(appendChild).toHaveBeenCalled();
14  expect(removeChild).toHaveBeenCalled();
15
16  mockCreateObjectURL.mockRestore();
17  mockRevokeObjectURL.mockRestore();
18});