commit: save commit message so it's not destroyed by rollback.
(
issue1635)
Rationale: if a pretxncommit hook rejects this commit, the transaction
is rolled back and the user's commit message is irrevocably lost.
So save a copy in .hg/last-message.txt, just in case. Also handy if
the user deliberately rolls back a commit in order to amend it.
#!/bin/sh
mkdir t
cd t
hg init
echo a > a
hg add a
hg commit -m test
# do we ever miss a sub-second change?
for i in 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20; do
hg co -qC 0
echo b > a
hg st
done