tests/test-rollback

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

mkdir t
cd t
hg init
echo a > a
hg add a
hg commit -m "test" -d "1000000 0"
hg verify
hg parents
hg status
hg rollback
hg verify
hg parents
hg status

echo % Test issue 902
hg commit -m "test2"
hg branch test
hg rollback
hg branch

echo '% Test issue 1635 (commit message saved)'
echo '.hg/last-message.txt:'
cat .hg/last-message.txt ; echo

echo % Test rollback of hg before issue 902 was fixed
hg commit -m "test3"
hg branch test
rm .hg/undo.branch
hg rollback
hg branch

echo '% rollback by pretxncommit saves commit message (issue 1635)'
echo a >> a
hg --config hooks.pretxncommit=false commit -m"precious commit message" 2>&1 | sed 's,exited with status .*,exited ...,g'
echo '.hg/last-message.txt:'
cat .hg/last-message.txt ; echo

echo '% same thing, but run $EDITOR'
cat > $HGTMP/editor <<'__EOF__'
#!/bin/sh
echo "another precious commit message" > "$1"
__EOF__
chmod +x $HGTMP/editor
HGEDITOR=$HGTMP/editor hg --config hooks.pretxncommit=false commit 2>&1 | sed 's,exited with status .*,exited ...,g'
echo '.hg/last-message.txt:'
cat .hg/last-message.txt