Some forms of authors don't round-trip
Created originally on Bitbucket by glandium (Mike Hommey)
See the following reduced testcase:
#!shell
$ mkdir a b
$ cd b
$ git init --bare
$ cd ../a
$ hg init
$ echo a > a
$ hg commit -A -m a -u foo@bar
$ hg push ../b
$ cd ..
$ hg clone b c
The changeset in c doesn't have the same sha1 as the one in a because the author changed from foo@bar
to foo@bar <foo@bar>
. Reading the code, there are likely other forms that don't round-trip.
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