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.
adding a
adding b/b
% file replaced with directory
% should fail - would corrupt dirstate
abort: file 'a' in dirstate clashes with 'a/a'
% removing shadow
% should succeed - shadow removed
% directory replaced with file
% should fail - would corrupt dirstate
abort: directory 'b' already in dirstate
% removing shadow
% should succeed - shadow removed
% look what we got
A a/a
A b
R a
R b/b
% revert reintroducing shadow - should fail
abort: file 'b' in dirstate clashes with 'b/b'
% revert all - should succeed
undeleting a
forgetting a/a
forgetting b
undeleting b/b
% addremove
removing a
adding a/a
adding b
removing b/b
A a/a
A b
R a
R b/b
% commit
C a/a
C b
% long directory replaced with file
adding d/d/d
% should fail - would corrupt dirstate
abort: directory 'd' already in dirstate
% removing shadow
% should succeed - shadow removed
% update should work at least with clean workdir
2 files updated, 0 files merged, 0 files removed, 0 files unresolved
C a
C b/b
2 files updated, 0 files merged, 0 files removed, 0 files unresolved
C a/a
C b