question about NSS [SUCCESS=merge] semantics

[DJ Delorie]

If two services both have the same user in a given group, and the
merge feature needs to merge them, do we de-duplicate the user or not?
Do we also dedup the groups when enumerating?

The wiki proposing the feature says to dedup, but neither the man page
nor the patch submission mentions it.

I.e.

group	test1 [SUCCESS=merge] test2

with...

test1:  mygroup::4:alpha,beta,gamma

test2:  mygroup::4:alpha,delta

There are two interesting cases (well, three):

getgrgid(4) -> alpha,beta,gamma,delta
-OR-
getgrgid(4) -> alpha,beta,gamma,alpha,delta

and also:

getgrent() returns which?

mygroup:4:alpha,beta,gamma,delta
-OR-
mygroup:4:alpha,beta,gamma,alpha,delta
-OR-
mygroup:4:alpha,beta,gamma,delta
mygroup:4:alpha,delta

(i.e. two parts: dedup users, and/or dedup groups)