Segfault when printing vf-metadata name

[Argon-]

Two dummy entries for input.conf:

n vf add @mf:format=yuv420p
m show_text "${vf-metadata/mf}"

As long as n was not pressed, m displays the expected "(error)" string. However, once n was pressed (and the filter successfully added), m results in mpv segfaulting.

Thread 7 Crashed:: mpv/playback core (OSX)
0   ???                                 000000000000000000 0 + 0
1   mpv                                 0x0000000109e506b7 mp_property_vf_metadata + 103
2   mpv                                 0x0000000109e42e8c do_action + 316
3   mpv                                 0x0000000109e42814 m_property_do + 372
4   mpv                                 0x0000000109e433c9 m_properties_expand_string + 1177
5   mpv                                 0x0000000109e4bb72 run_command + 290
6   mpv                                 0x0000000109e6358b mp_process_input + 27
7   mpv                                 0x0000000109e652a2 run_playloop + 2322
8   mpv                                 0x0000000109e5b6d8 mp_play_files + 4776
9   mpv                                 0x0000000109e5cfdd mpv_main + 1053
10  mpv                                 0x0000000109ec61c9 playback_thread + 41
11  libsystem_pthread.dylib             0x00007fff8fd8e2fc _pthread_body + 131
12  libsystem_pthread.dylib             0x00007fff8fd8e279 _pthread_start + 176
13  libsystem_pthread.dylib             0x00007fff8fd8c4b1 thread_start + 13

Am I doing it wrong or is it a bug?

[ghost]

Was a bug; fixed it. There's no metadata with this filter, so it'll still display "error".

[Argon-]

Thanks :)
I wanted to use this property as some kind of "is this filter already added" check. Is there some other way to do this?

[ghost]

OK, made a small change, see commit above.

[Argon-]

Works as expected, thanks!