[JimmXinu]

@cryosaur -

First off, I'll tell you the same thing I tell everyone trying to normalize AO3 metadata: it's going to be a lot of work and it's never going to be perfect as long as AO3 allows authors to enter whatever they want.

As for the possible bug:

The way it works is that include/exclude_pre then replace_metadata then include/exclude_post are applied to each metadata entry as it's used, not all metadata as a whole.

So when you use warnings in a conditional clause, the pre, replace_metadata and post lines for warnings are applied to it before it is used.

I can see where that fact is non-intuitive. I'm going to look at the wiki pages and add some documentation about that.

There are ways to accomplish what you want even with that limitation:

Create a new metadata entry containing a copy of warnings that isn't edited for conditionals:

# Partial solution
[archiveofourown.org]
add_to_extra_valid_entries:,rawwarnings
include_in_rawwarnings:warnings.NOREPL

add_to_replace_metadata:
 freeformtags=>(.*)=>\1\,Violence&&rawwarnings=>Graphic Depictions Of Violence

exclude_metadata_post:
 warnings==Graphic Depictions Of Violence

But as you noticed, if there's nothing in freeformtags, the replacement isn't made.

IMO, it's better the create a new metadata entry containing a copy of warnings that you apply your edits and filters to that you include in freeformtags:

# More complete solution
[archiveofourown.org]
add_to_extra_valid_entries:,abbrevwarnings
include_in_abbrevwarnings:warnings.NOREPL
include_in_freeformtags:freeformtags,abbrevwarnings

add_to_replace_metadata:
 abbrevwarnings=>^Graphic Depictions Of Violence$=>Violence
 abbrevwarnings=>^Major Character Death$=>Death

include_metadata_post:
 abbrevwarnings==Violence
 abbrevwarnings==Death
 
exclude_metadata_post:
 warnings==Graphic Depictions Of Violence
 warnings==Major Character Death