tests/test-rollback.t

transaction: quietly rollback if no other changes than temporary files

If no actual change have been made, we don't really need to roll them back. We
only have to cleanup some temporary files and it seems reasonable to do that
quietly.

This will help us to use the transaction in wider context¹ without impacting the
user experience.

[1] as in Python context managers that lives longer.

setup repo
  $ hg init t
  $ cd t
  $ echo a > a
  $ hg add a
  $ hg commit -m 'add a'
  $ hg verify -q
  $ hg parents
  changeset:   0:1f0dee641bb7
  tag:         tip
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     add a
  

rollback to null revision
  $ hg status
  $ hg rollback
  repository tip rolled back to revision -1 (undo commit)
  working directory now based on revision -1
  $ hg verify -q
  $ hg parents
  $ hg status
  A a

Two changesets this time so we rollback to a real changeset
  $ hg commit -m'add a again'
  $ echo a >> a
  $ hg commit -m'modify a'

Test issue 902 (current branch is preserved)
  $ hg branch test
  marked working directory as branch test
  (branches are permanent and global, did you want a bookmark?)
  $ hg rollback
  repository tip rolled back to revision 0 (undo commit)
  working directory now based on revision 0
  $ hg branch
  default

Test issue 1635 (commit message saved)
  $ cat .hg/last-message.txt ; echo
  modify a

Test rollback of hg before issue 902 was fixed

  $ hg commit -m "test3"
  $ hg branch test
  marked working directory as branch test
  (branches are permanent and global, did you want a bookmark?)
  $ rm .hg/undo.branch
  $ hg rollback
  repository tip rolled back to revision 0 (undo commit)
  named branch could not be reset: current branch is still 'test'
  working directory now based on revision 0
  $ hg branch
  test

working dir unaffected by rollback: do not restore dirstate et. al.
  $ hg log --template '{rev}  {branch}  {desc|firstline}\n'
  0  default  add a again
  $ hg status
  M a
  $ hg bookmark foo
  $ hg commit -m'modify a again'
  $ echo b > b
  $ hg bookmark bar -r default #making bar active, before the transaction
  $ hg commit -Am'add b'
  adding b
  $ hg log --template '{rev}  {branch}  {desc|firstline}\n'
  2  test  add b
  1  test  modify a again
  0  default  add a again
  $ hg update bar
  1 files updated, 0 files merged, 1 files removed, 0 files unresolved
  (activating bookmark bar)
  $ cat .hg/undo.branch ; echo
  test
  $ hg rollback -f
  repository tip rolled back to revision 1 (undo commit)
  $ hg id -n
  0
  $ hg branch
  default
  $ cat .hg/bookmarks.current ; echo
  bar
  $ hg bookmark --delete foo bar

rollback by pretxncommit saves commit message (issue1635)

  $ echo a >> a
  $ hg --config hooks.pretxncommit=false commit -m"precious commit message"
  transaction abort!
  rollback completed
  abort: pretxncommit hook exited with status * (glob)
  [40]
  $ cat .hg/last-message.txt ; echo
  precious commit message

same thing, but run $EDITOR

  $ cat > editor.sh << '__EOF__'
  > echo "another precious commit message" > "$1"
  > __EOF__
  $ HGEDITOR="\"sh\" \"`pwd`/editor.sh\"" hg --config hooks.pretxncommit=false commit 2>&1
  transaction abort!
  rollback completed
  note: commit message saved in .hg/last-message.txt
  note: use 'hg commit --logfile .hg/last-message.txt --edit' to reuse it
  abort: pretxncommit hook exited with status * (glob)
  [40]
  $ cat .hg/last-message.txt
  another precious commit message

test rollback on served repository

#if serve
  $ hg commit -m "precious commit message"
  $ hg serve -p $HGPORT -d --pid-file=hg.pid -A access.log -E errors.log
  $ cat hg.pid >> $DAEMON_PIDS
  $ cd ..
  $ hg clone http://localhost:$HGPORT u
  requesting all changes
  adding changesets
  adding manifests
  adding file changes
  added 3 changesets with 2 changes to 1 files (+1 heads)
  new changesets 23b0221f3370:068774709090
  updating to branch default
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ cd u
  $ hg id default
  068774709090

now rollback and observe that 'hg serve' reloads the repository and
presents the correct tip changeset:

  $ hg -R ../t rollback
  repository tip rolled back to revision 1 (undo commit)
  working directory now based on revision 0
  $ hg id default
  791dd2169706

  $ killdaemons.py
#endif

update to older changeset and then refuse rollback, because
that would lose data (issue2998)
  $ cd ../t
  $ hg -q update
  $ rm `hg status -un`
  $ template='{rev}:{node|short}  [{branch}]  {desc|firstline}\n'
  $ echo 'valuable new file' > b
  $ echo 'valuable modification' >> a
  $ hg commit -A -m'a valuable change'
  adding b
  $ hg update 0
  1 files updated, 0 files merged, 1 files removed, 0 files unresolved
  $ hg rollback
  abort: rollback of last commit while not checked out may lose data
  (use -f to force)
  [255]
  $ hg tip -q
  2:4d9cd3795eea
  $ hg rollback -f
  repository tip rolled back to revision 1 (undo commit)
  $ hg status
  $ hg log --removed b   # yep, it's gone

same again, but emulate an old client that doesn't write undo.desc
  $ hg -q update
  $ echo 'valuable modification redux' >> a
  $ hg commit -m'a valuable change redux'
  $ rm .hg/undo.desc
  $ hg update 0
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ hg rollback
  rolling back unknown transaction
  $ cat a
  a

corrupt journal test
  $ echo "foo" > .hg/store/journal
  $ hg recover --verify -q
  couldn't read journal entry 'foo\n'!

rollback disabled by config
  $ cat >> $HGRCPATH <<EOF
  > [ui]
  > rollback = false
  > EOF
  $ echo narf >> pinky-sayings.txt
  $ hg add pinky-sayings.txt
  $ hg ci -m 'First one.'
  $ hg rollback
  abort: rollback is disabled because it is unsafe
  (see `hg help -v rollback` for information)
  [255]

  $ cd ..

I/O errors on stdio are handled properly (issue5658)

  $ cat > badui.py << EOF
  > import errno
  > from mercurial.i18n import _
  > from mercurial import (
  >     error,
  >     registrar,
  >     ui as uimod,
  > )
  > 
  > configtable = {}
  > configitem = registrar.configitem(configtable)
  > 
  > configitem(b'ui', b'ioerrors',
  >     default=list,
  > )
  > 
  > def pretxncommit(ui, repo, **kwargs):
  >     ui.warn(b'warn during pretxncommit\n')
  > 
  > def pretxnclose(ui, repo, **kwargs):
  >     ui.warn(b'warn during pretxnclose\n')
  > 
  > def txnclose(ui, repo, **kwargs):
  >     ui.warn(b'warn during txnclose\n')
  > 
  > def txnabort(ui, repo, **kwargs):
  >     ui.warn(b'warn during abort\n')
  > 
  > class fdproxy(object):
  >     def __init__(self, ui, o):
  >         self._ui = ui
  >         self._o = o
  > 
  >     def __getattr__(self, attr):
  >         return getattr(self._o, attr)
  > 
  >     def write(self, msg):
  >         errors = set(self._ui.configlist(b'ui', b'ioerrors'))
  >         pretxncommit = msg == b'warn during pretxncommit\n'
  >         pretxnclose = msg == b'warn during pretxnclose\n'
  >         txnclose = msg == b'warn during txnclose\n'
  >         txnabort = msg == b'warn during abort\n'
  >         msgabort = msg == _(b'transaction abort!\n')
  >         msgrollback = msg == _(b'rollback completed\n')
  > 
  >         if pretxncommit and b'pretxncommit' in errors:
  >             raise IOError(errno.EPIPE, 'simulated epipe')
  >         if pretxnclose and b'pretxnclose' in errors:
  >             raise IOError(errno.EIO, 'simulated eio')
  >         if txnclose and b'txnclose' in errors:
  >             raise IOError(errno.EBADF, 'simulated badf')
  >         if txnabort and b'txnabort' in errors:
  >             raise IOError(errno.EPIPE, 'simulated epipe')
  >         if msgabort and b'msgabort' in errors:
  >             raise IOError(errno.EBADF, 'simulated ebadf')
  >         if msgrollback and b'msgrollback' in errors:
  >             raise IOError(errno.EIO, 'simulated eio')
  > 
  >         return self._o.write(msg)
  > 
  > def uisetup(ui):
  >     class badui(ui.__class__):
  >         def _write(self, dest, *args, **kwargs):
  >             olderr = self.ferr
  >             try:
  >                 if dest is self.ferr:
  >                     self.ferr = dest = fdproxy(self, olderr)
  >                 return super(badui, self)._write(dest, *args, **kwargs)
  >             finally:
  >                 self.ferr = olderr
  > 
  >     ui.__class__ = badui
  > 
  > def reposetup(ui, repo):
  >     ui.setconfig(b'hooks', b'pretxnclose.badui', pretxnclose, b'badui')
  >     ui.setconfig(b'hooks', b'txnclose.badui', txnclose, b'badui')
  >     ui.setconfig(b'hooks', b'pretxncommit.badui', pretxncommit, b'badui')
  >     ui.setconfig(b'hooks', b'txnabort.badui', txnabort, b'badui')
  > EOF

  $ cat >> $HGRCPATH << EOF
  > [extensions]
  > badui = $TESTTMP/badui.py
  > EOF

An I/O error during pretxncommit is handled

  $ hg init ioerror-pretxncommit
  $ cd ioerror-pretxncommit
  $ echo 0 > foo
  $ hg -q commit -A -m initial
  warn during pretxncommit
  warn during pretxnclose
  warn during txnclose
  $ echo 1 > foo
  $ hg --config ui.ioerrors=pretxncommit commit -m 'error during pretxncommit'
  warn during pretxnclose
  warn during txnclose

  $ hg commit -m 'commit 1'
  nothing changed
  [1]

  $ cd ..

An I/O error during pretxnclose is handled

  $ hg init ioerror-pretxnclose
  $ cd ioerror-pretxnclose
  $ echo 0 > foo
  $ hg -q commit -A -m initial
  warn during pretxncommit
  warn during pretxnclose
  warn during txnclose

  $ echo 1 > foo
  $ hg --config ui.ioerrors=pretxnclose commit -m 'error during pretxnclose'
  warn during pretxncommit
  warn during txnclose

  $ hg commit -m 'commit 1'
  nothing changed
  [1]

  $ cd ..

An I/O error during txnclose is handled

  $ hg init ioerror-txnclose
  $ cd ioerror-txnclose
  $ echo 0 > foo
  $ hg -q commit -A -m initial
  warn during pretxncommit
  warn during pretxnclose
  warn during txnclose

  $ echo 1 > foo
  $ hg --config ui.ioerrors=txnclose commit -m 'error during txnclose'
  warn during pretxncommit
  warn during pretxnclose

  $ hg commit -m 'commit 1'
  nothing changed
  [1]

  $ cd ..

An I/O error writing "transaction abort" is handled

  $ hg init ioerror-msgabort
  $ cd ioerror-msgabort

  $ echo 0 > foo
  $ hg -q commit -A -m initial
  warn during pretxncommit
  warn during pretxnclose
  warn during txnclose

  $ echo 1 > foo
  $ hg --config ui.ioerrors=msgabort --config hooks.pretxncommit=false commit -m 'error during abort message'
  warn during abort
  rollback completed
  abort: pretxncommit hook exited with status 1
  [40]

  $ hg commit -m 'commit 1'
  warn during pretxncommit
  warn during pretxnclose
  warn during txnclose

  $ cd ..

An I/O error during txnabort should still result in rollback

  $ hg init ioerror-txnabort
  $ cd ioerror-txnabort

  $ echo 0 > foo
  $ hg -q commit -A -m initial
  warn during pretxncommit
  warn during pretxnclose
  warn during txnclose

  $ echo 1 > foo
  $ hg --config ui.ioerrors=txnabort --config hooks.pretxncommit=false commit -m 'error during abort'
  transaction abort!
  rollback completed
  abort: pretxncommit hook exited with status 1
  [40]

  $ hg commit -m 'commit 1'
  warn during pretxncommit
  warn during pretxnclose
  warn during txnclose

  $ cd ..

An I/O error writing "rollback completed" is handled

  $ hg init ioerror-msgrollback
  $ cd ioerror-msgrollback

  $ echo 0 > foo
  $ hg -q commit -A -m initial
  warn during pretxncommit
  warn during pretxnclose
  warn during txnclose

  $ echo 1 > foo

  $ hg --config ui.ioerrors=msgrollback --config hooks.pretxncommit=false commit -m 'error during rollback message'
  transaction abort!
  warn during abort
  abort: pretxncommit hook exited with status 1
  [40]

  $ hg verify -q

  $ cd ..

Multiple I/O errors after transaction open are handled.
This is effectively what happens if a peer disconnects in the middle
of a transaction.

  $ hg init ioerror-multiple
  $ cd ioerror-multiple
  $ echo 0 > foo
  $ hg -q commit -A -m initial
  warn during pretxncommit
  warn during pretxnclose
  warn during txnclose

  $ echo 1 > foo

  $ hg --config ui.ioerrors=pretxncommit,pretxnclose,txnclose,txnabort,msgabort,msgrollback commit -m 'multiple errors'

  $ hg verify -q

  $ cd ..