[Gnu-arch-users] meaning of untagged_is_source is inv_tags.c

[Bruce Stephens]

Something's recently changed such that untagged files (in tagline)
aren't regarded as source files, at least some of the time.  So "tla
file-find" claims they're new files (even though they're not), and
(probably more importantly) "tla undo" doesn't notice the changes
(although "tla what-changed" does).

(This is bug 5554.)

I've been trying to work out what's going on, and the closest I've got
is that arch_file_get_or_diff calls arch_inventory_tag with the second
parameter 0, and then arch_inventory_tag doesn't change that,
regardless of what tagging method it actually finds.

Has anyone fixed this?  How is this supposed to work?  It seems to me
that whether or not an untagged file might be source depends only on
the tagging method, so why is this parameter being passed down along
with the tagging method?