imerge: fix ancestor calculation
If wctx already has two parents, ancestor calculation is wrong.
Normally merge is called before wctx gets the second parent, so
we simulate this in imerge by temporarily popping the second parent
before calling filemerge. Highly dirty.
This patch also handles the ParseError move from cmdutil to dispatch.
#!/bin/sh
hg init a
echo a > a/a
hg --cwd a ci -Ama
hg clone a c
hg clone a b
echo b >> b/a
hg --cwd b ci -mb
echo % push should push to default when default-push not set
hg --cwd b push | sed 's/pushing to.*/pushing/'
echo % push should push to default-push when set
echo 'default-push = ../c' >> b/.hg/hgrc
hg --cwd b push | sed 's/pushing to.*/pushing/'