def METHOD_NAME(mocker: MockerFixture, tmp_path: Path) -> None:
    # Use write_bytes() so that the line endings are the same on POSIX and
    # Windows.
    (tmp_path / "file1.txt").write_bytes(b"This is the first file.\n")
    (tmp_path / "file2.txt").write_bytes(b"This is the second file.\n")
    sub1 = tmp_path / "sub1"
    sub1.mkdir()
    (sub1 / "file3.txt").write_bytes(b"This is the third file.\n")
    (sub1 / "file4.txt").write_bytes(b"This is the fourth file.\n")
    (sub1 / "file5.txt").write_bytes(b"This is the fifth file.\n")
    subsub = sub1 / "subsub"
    subsub.mkdir()
    (subsub / "file6.txt").write_bytes(b"This is the sixth file.\n")
    sub2 = tmp_path / "sub2"
    sub2.mkdir()
    (sub2 / "file7.txt").write_bytes(b"This is the seventh file.\n")
    (sub2 / "file8.txt").write_bytes(b"This is the eighth file.\n")
    empty = tmp_path / "empty"
    empty.mkdir()
    assert (
        get_zarr_checksum(tmp_path / "file1.txt") == "d0aa42f003e36c1ecaf9aa8f20b6f1ad"
    )
    assert get_zarr_checksum(tmp_path) == "25627e0fc7c609d10100d020f7782a25-8--197"
    assert get_zarr_checksum(sub1) == "64af93ad7f8d471c00044d1ddbd4c0ba-4--97"
    assert get_zarr_checksum(empty) == "481a2f77ab786a0f45aafd5db0971caa-0--0"
    spy = mocker.spy(digests, "md5file_nocache")
    assert (
        get_zarr_checksum(
            tmp_path,
            known={
                "file1.txt": "9ee7a152c5adb60803c928733acc1533",
                # ^^ This one is different!
                "file2.txt": "340c108ee69bf4626e7995a7048f52b8",
                "sub1/file3.txt": "7351dc767bfad322ddce50401badc359",
                "sub1/file4.txt": "bbede70f39fa8fc34f2dc4eda8b6bdea",
                "sub1/file5.txt": "c4e828c509f90b84e5b72d9d5612d676",
                "sub1/subsub/file6.txt": "6a7fe3b9e2c69a54216b7d5dcb4fe61d",
                # "sub2/file7.txt": Absent!
                "sub2/file8.txt": "7aadbff2b21f438baccded18b2e81ae3",
                "nonexistent-file.txt": "123456789012345678901234567890ab",
                # ^^ Not used in calculation!
            },
        )
        == "f77f4c5b277575f781c19ba91422f0c5-8--197"
    )
    spy.assert_called_once_with(sub2 / "file7.txt")