def test_mpris2_deprecated_format(patched_module):
    """
    Previously, metadata was displayed by using a list of fields.
    Now, we use a `format` string. The widget should create this when a user
    provides `display_metadata` in their config.
    """
    mp = patched_module.Mpris2(display_metadata=["xesam:title", "xesam:artist"])
    assert mp.format == "{xesam:title} - {xesam:artist}"

    Previously, metadata was displayed by using a list of fields.
    Now, we use a `format` string. The widget should create this when a user
    provides `display_metadata` in their config.
    
test/widgets/test_mpris2widget.py