'scrub' doesn't scrub

[simonbcn]

beets git version

beets version 1.3.16
plugins: convert, embedart, fetchart, info, lastgenre, replaygain, scrub

I import a FLAC file with a comment tag but scrub doesn't delete it.

[sampsyo]

Scrub is not supposed to delete the command tag. Perhaps you meant to use the zero plugin?

[simonbcn]

https://beets.readthedocs.org/en/v1.3.15/plugins/scrub.html

Scrub Plugin
The scrub plugin lets you remove extraneous metadata from files’ tags. If you’d prefer never to see crufty tags that come from other tools, the plugin can automatically remove all non-beets-tracked tags whenever a file’s metadata is written to disk by removing the tag entirely before writing new data.
...
Automatic Scrubbing
To automatically remove files’ tags before writing new ones, just enable the scrub plugin ...

By reading this I've understood that scrub would remove all tags before save the new ones.

[simonbcn]

With the zero plugin, it writes garbage to the comment field:

....
zero:
  fields: comments
  update_database: true

beet info -i comment ... doesn't show anything but:

$ mid3v2 -l Música/Avicii/Stories/01\ -\ Waiting\ for\ Love.mp3             
IDv2 tag info for Música/Avicii/Stories/01 - Waiting for Love.mp3 
COMM=iTunNORM=eng= 00002206 00002206 0000550E 0000550E 00000000 00000000 00008E88 00008E88 00000000 00000000
....

[sampsyo]

Ah, I understand how that could be unclear. The plugin removes everything beets doesn't support, but built-in beets fields (including comments) are preserved.

iTunNORM is an embodiment of the ReplayGain tag.

[m-urban]

Just stumbled over this issue and have to cross-link to another comment for future reference, as it contains the explanation for a problem that I was losing some hair over:

@sampsyo said:

Are you referring to the iTunNORM field? That’s not considered a comment by beets; it’s an implementation of ReplayGain normalization. Unfortunately, eyed3 labels it as a “comment” for some reason.

This applies to eyeD3, evidently amaroK, too, and probably other players/tools as well…