def test_read_nonexistring_calendar(capsys):
    sch = Scheduler()
    with pytest.raises(Exception) as excinfo:
        sch.read_calendar(file='non_existring_file.extension')
    cp = capsys.readouterr()
    assert not cp.out
    assert 'No such file or directory:' in str(excinfo.value)
def test_read_empty_calendar(capsys):
    sch = Scheduler()
    with pytest.raises(Exception) as excinfo:
        sch.read_calendar(file='tests/empty.ics')
    cp = capsys.readouterr()
    assert not cp.out
    assert 'Multiple calendars in one file are not supported by this method.' in str(
        excinfo.value)