Modifying "genre" instead of "genres" fails silently

[lueckem]

Problem

As already discussed in #6465, the "genre" field is now called "genres".
If I still use "genre", e.g.,

$ beet mod -a "name" genre=Rock

the command sets the field "genre" in the database, but does not write to the genre tag of the music files.
While this is technically correct behavior, it is almost never what the user actually wants. It took me quite a bit of time to figure out what was going wrong.

Suggestion:
Instead of "failing" silently, print a warning or info if the "genre" field is modified. For example

Warning: Use the field "genres" instead of "genre" to modify the genre.

Thanks for your good work!

Setup

• OS: Archlinux
• Python version: 3.14.3
• beets version: 2.7.1
• Turning off plugins made problem go away (yes/no): no

[snejus]

Good point. Would you expect to the field to be converted to genres automatically in this case?

[snejus]

What I meant by above:

[snejus]

Currently, beet mod -a "name" genre=Rock ends up writing a flexible field genre. The solution above would make it impossible to write genre specifically, but presumably that's something that users never really intend to do? 🤔

[lueckem]

Currently, beet mod -a "name" genre=Rock ends up writing a flexible field genre. The solution above would make it impossible to write genre specifically, but presumably that's something that users never really intend to do? 🤔

I like the solution!
Of course I cannot speak for everyone, but I can't think of a scenario where you would want to modify the non-standard field "genre" that does not actually get written to the music files.

[snejus]

Makes sense.

Another question: what about queries beet list genre:rock? Should we supply a warning suggesting users to use genres field?

[lueckem]

Another question: what about queries beet list genre:rock? Should we supply a warning suggesting users to use genres field?

Yes, I think a warning for list would also be very helpful.