view tests/test-bheads.t @ 50195:11e6eee4b063

transaction: use the standard transaction mechanism to backup branch

Branch is a bit special :
- It currently does not collaborate with the transaction (or any scoping) for
  writing (this is bad)
- It can change without the lock being taken (it is protected by `wlock`)

So we rely on the same mechanism as for the backup of the other dirstate file:
- we only do a backup if we hold the wlock
- we force a backup though the transaction


Since "branch" write does not collaborate with the transaction, we cannot back
it up "at the last minute" as we do for the dirstate. We have to back it up
"upfront". Since we have a backup, the transaction is no longer doing its
"quick_abort" and get noisy. Which is quite annoying. To work around this, and
to avoid jumping in yet-another-rabbit-hole of "getting branch written
properly", I am doing horrible things to the transaction in the meantime.
We should be able to get this code go away during the next cycle.

In the meantime, I prefer to take this small stop so that we stop abusing the
"journal" and "undo" mechanism instead of the proper backup mechanism of the
transaction.


Also note that this change regress the warning message for the legacy fallback
introduced in 2008 when issue902 got fixed in dd5a501cb97f (Mercurial 1.0).

I feel like this is fine as issue 902 remains fixed, and this would only affect
people deploying a mix of 15 year old Mercurial and modern mercurial, and using
branch and rollback extensively.

  $ heads()
  > {
  >    hg heads --template '{rev}: {desc|firstline|strip} ({branches})\n' "$@"
  > }

  $ hg init a
  $ cd a
  $ echo 'root' >root
  $ hg add root
  $ hg commit -m "Adding root node"
  $ heads
  0: Adding root node ()
-------
  $ heads .
  0: Adding root node ()

=======

  $ echo 'a' >a
  $ hg add a
  $ hg branch a
  marked working directory as branch a
  (branches are permanent and global, did you want a bookmark?)
  $ hg commit -m "Adding a branch"
  $ heads
  1: Adding a branch (a)
  0: Adding root node ()
-------
  $ heads .
  1: Adding a branch (a)

=======

  $ hg update -C 0
  0 files updated, 0 files merged, 1 files removed, 0 files unresolved
  $ echo 'b' >b
  $ hg add b
  $ hg branch b
  marked working directory as branch b
  $ hg commit -m "Adding b branch"
  $ heads
  2: Adding b branch (b)
  1: Adding a branch (a)
  0: Adding root node ()
-------
  $ heads .
  2: Adding b branch (b)

=======

  $ echo 'bh1' >bh1
  $ hg add bh1
  $ hg commit -m "Adding b branch head 1"
  $ heads
  3: Adding b branch head 1 (b)
  1: Adding a branch (a)
  0: Adding root node ()
-------
  $ heads .
  3: Adding b branch head 1 (b)

=======

  $ hg update -C 2
  0 files updated, 0 files merged, 1 files removed, 0 files unresolved
  $ echo 'bh2' >bh2
  $ hg add bh2
  $ hg commit -m "Adding b branch head 2"
  created new head
  $ heads
  4: Adding b branch head 2 (b)
  3: Adding b branch head 1 (b)
  1: Adding a branch (a)
  0: Adding root node ()
  $ heads .
  4: Adding b branch head 2 (b)
  3: Adding b branch head 1 (b)

=======

  $ hg update -C 2
  0 files updated, 0 files merged, 1 files removed, 0 files unresolved
  $ echo 'bh3' >bh3
  $ hg add bh3
  $ hg commit -m "Adding b branch head 3"
  created new head
  $ heads
  5: Adding b branch head 3 (b)
  4: Adding b branch head 2 (b)
  3: Adding b branch head 1 (b)
  1: Adding a branch (a)
  0: Adding root node ()
-------
  $ heads .
  5: Adding b branch head 3 (b)
  4: Adding b branch head 2 (b)
  3: Adding b branch head 1 (b)

=======

  $ hg merge 4
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  (branch merge, don't forget to commit)
  $ hg commit -m "Merging b branch head 2 and b branch head 3"
  $ heads
  6: Merging b branch head 2 and b branch head 3 (b)
  3: Adding b branch head 1 (b)
  1: Adding a branch (a)
  0: Adding root node ()
-------
  $ heads .
  6: Merging b branch head 2 and b branch head 3 (b)
  3: Adding b branch head 1 (b)

=======

  $ echo 'c' >c
  $ hg add c
  $ hg branch c
  marked working directory as branch c
  $ hg commit -m "Adding c branch"
  $ heads
  7: Adding c branch (c)
  6: Merging b branch head 2 and b branch head 3 (b)
  3: Adding b branch head 1 (b)
  1: Adding a branch (a)
  0: Adding root node ()
-------
  $ heads .
  7: Adding c branch (c)

=======

  $ heads -r 3 .
  no open branch heads found on branches c (started at 3)
  [1]
  $ heads -r 2 .
  7: Adding c branch (c)
-------
  $ hg update -C 4
  0 files updated, 0 files merged, 2 files removed, 0 files unresolved
-------
  $ heads -r 3 .
  3: Adding b branch head 1 (b)
-------
  $ heads -r 2 .
  6: Merging b branch head 2 and b branch head 3 (b)
  3: Adding b branch head 1 (b)
-------
  $ heads -r 7 .
  no open branch heads found on branches b (started at 7)
  [1]

=======

  $ for i in 0 1 2 3 4 5 6 7; do
  >     hg update -C "$i"
  >     heads
  >     echo '-------'
  >     heads .
  >     echo '-------'
  > done
  0 files updated, 0 files merged, 2 files removed, 0 files unresolved
  7: Adding c branch (c)
  6: Merging b branch head 2 and b branch head 3 (b)
  3: Adding b branch head 1 (b)
  1: Adding a branch (a)
  0: Adding root node ()
  -------
  0: Adding root node ()
  -------
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  7: Adding c branch (c)
  6: Merging b branch head 2 and b branch head 3 (b)
  3: Adding b branch head 1 (b)
  1: Adding a branch (a)
  0: Adding root node ()
  -------
  1: Adding a branch (a)
  -------
  1 files updated, 0 files merged, 1 files removed, 0 files unresolved
  7: Adding c branch (c)
  6: Merging b branch head 2 and b branch head 3 (b)
  3: Adding b branch head 1 (b)
  1: Adding a branch (a)
  0: Adding root node ()
  -------
  6: Merging b branch head 2 and b branch head 3 (b)
  3: Adding b branch head 1 (b)
  -------
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  7: Adding c branch (c)
  6: Merging b branch head 2 and b branch head 3 (b)
  3: Adding b branch head 1 (b)
  1: Adding a branch (a)
  0: Adding root node ()
  -------
  6: Merging b branch head 2 and b branch head 3 (b)
  3: Adding b branch head 1 (b)
  -------
  1 files updated, 0 files merged, 1 files removed, 0 files unresolved
  7: Adding c branch (c)
  6: Merging b branch head 2 and b branch head 3 (b)
  3: Adding b branch head 1 (b)
  1: Adding a branch (a)
  0: Adding root node ()
  -------
  6: Merging b branch head 2 and b branch head 3 (b)
  3: Adding b branch head 1 (b)
  -------
  1 files updated, 0 files merged, 1 files removed, 0 files unresolved
  7: Adding c branch (c)
  6: Merging b branch head 2 and b branch head 3 (b)
  3: Adding b branch head 1 (b)
  1: Adding a branch (a)
  0: Adding root node ()
  -------
  6: Merging b branch head 2 and b branch head 3 (b)
  3: Adding b branch head 1 (b)
  -------
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  7: Adding c branch (c)
  6: Merging b branch head 2 and b branch head 3 (b)
  3: Adding b branch head 1 (b)
  1: Adding a branch (a)
  0: Adding root node ()
  -------
  6: Merging b branch head 2 and b branch head 3 (b)
  3: Adding b branch head 1 (b)
  -------
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  7: Adding c branch (c)
  6: Merging b branch head 2 and b branch head 3 (b)
  3: Adding b branch head 1 (b)
  1: Adding a branch (a)
  0: Adding root node ()
  -------
  7: Adding c branch (c)
  -------

=======

  $ for i in a b c z; do
  >     heads "$i"
  >     echo '-------'
  > done
  1: Adding a branch (a)
  -------
  6: Merging b branch head 2 and b branch head 3 (b)
  3: Adding b branch head 1 (b)
  -------
  7: Adding c branch (c)
  -------
  abort: unknown revision 'z'
  -------

=======

  $ heads 0 1 2 3 4 5 6 7
  7: Adding c branch (c)
  6: Merging b branch head 2 and b branch head 3 (b)
  3: Adding b branch head 1 (b)
  1: Adding a branch (a)
  0: Adding root node ()

Topological heads:

  $ heads -t
  7: Adding c branch (c)
  3: Adding b branch head 1 (b)
  1: Adding a branch (a)

  $ cd ..
______________

"created new head" message tests

  $ hg init newheadmsg
  $ cd newheadmsg

Init: no msg

  $ echo 1 > a
  $ hg ci -Am "a0: Initial root"
  adding a
  $ echo 2 >> a
  $ hg ci -m "a1 (HN)"

  $ hg branch b
  marked working directory as branch b
  (branches are permanent and global, did you want a bookmark?)
  $ echo 1 > b
  $ hg ci -Am "b2: Initial root for branch b"
  adding b
  $ echo 2 >> b
  $ hg ci -m "b3 (HN)"

Case NN: msg

  $ hg up -q null
  $ hg branch -f b
  marked working directory as branch b
  $ echo 1 > bb
  $ hg ci -Am "b4 (NN): new topo root for branch b"
  adding bb
  created new head

Case HN: no msg

  $ echo 2 >> bb
  $ hg ci -m "b5 (HN)"

Case BN: msg

  $ hg branch -f default
  marked working directory as branch default
  $ echo 1 > aa
  $ hg ci -Am "a6 (BN): new branch root"
  adding aa
  created new head

Case CN: msg

  $ hg up -q 4
  $ echo 3 >> bbb
  $ hg ci -Am "b7 (CN): regular new head"
  adding bbb
  created new head

Case BB: msg

  $ hg up -q 4
  $ hg merge -q 3
  $ hg branch -f default
  marked working directory as branch default
  $ hg ci -m "a8 (BB): weird new branch root"
  created new head

Case CB: msg

  $ hg up -q 4
  $ hg merge -q 1
  $ hg ci -m "b9 (CB): new head from branch merge"
  created new head

Case HB: no msg

  $ hg up -q 7
  $ hg merge -q 6
  $ hg ci -m "b10 (HB): continuing head from branch merge"

Case CC: msg

  $ hg up -q 4
  $ hg merge -q 2
  $ hg ci -m "b11 (CC): new head from merge"
  created new head

Case CH: no msg

  $ hg up -q 2
  $ hg merge -q 10
  $ hg ci -m "b12 (CH): continuing head from merge"

Case HH: no msg

  $ hg merge -q 3
  $ hg ci -m "b12 (HH): merging two heads"

  $ cd ..