tests/test-branch-option

prepush: add more precise error messages

Part of the patch is from [e-mail]

- indicate the branch name where there are multiple heads
- give better advice when hitting a possible race, where new heads are added
  between discovery and the call to branchmap(). In that case, asking the user
  to merge isn't helpful, since only remote has the changes.

#!/bin/sh

# test branch selection options
hg init branch
cd branch
hg branch a
echo a > foo
hg ci -d '0 0' -Ama
echo a2 > foo
hg ci -d '0 0' -ma2
hg up 0
hg branch c
echo c > foo
hg ci -d '0 0' -mc
cd ..
hg clone -r 0 branch branch2
cd branch2
hg up 0
hg branch b
echo b > foo
hg ci -d '0 0' -mb
hg up 0
hg branch -f b
echo b2 > foo
hg ci -d '0 0' -mb2

echo in rev c branch a
hg in -qr c ../branch#a
hg in -qr c -b a
echo out branch .
hg out -q ../branch#.
hg out -q -b .
echo clone branch b
cd ..
hg clone branch2#b branch3
hg -q -R branch3 heads b
hg -q -R branch3 parents
rm -rf branch3
echo clone rev a branch b
hg clone -r a branch2#b branch3
hg -q -R branch3 heads b
hg -q -R branch3 parents
rm -rf branch3