tests/test-extra-filelog-entry.t

fuzz: clean up some repetition on building parsers.so fuzzers

There was a lot of repetition here that I realized could be cleared out. I
think there's some more work we could do here, but this is enough for now.

Differential Revision: https://phab.mercurial-scm.org/D7568

Issue351: mq: qrefresh can create extra revlog entry

  $ echo "[extensions]" >> $HGRCPATH
  $ echo "mq=" >> $HGRCPATH

  $ hg init
  $ hg qinit

  $ echo b > b
  $ hg ci -A -m foo
  adding b

  $ echo cc > b
  $ hg qnew -f foo.diff
  $ echo b > b
  $ hg qrefresh

  $ hg debugindex b
     rev linkrev nodeid       p1           p2
       0       0 1e88685f5dde 000000000000 000000000000