def METHOD_NAME(self) -> None:
    with self.assertRaisesRegex(RuntimeError, "Parsing subvolume JSON"):
        subvolume_on_disk.SubvolumeOnDisk.from_json_file(
            io.StringIO("invalid json"), Path("/subvols")
        )
    with self.assertRaisesRegex(RuntimeError, "Parsed subvolume JSON"):
        subvolume_on_disk.SubvolumeOnDisk.from_json_file(
            io.StringIO("5"), Path("/subvols")
        )