view tests/test-rollback.t @ 42619:20d0e59be79b

tests: show the files fields of changelogs for many merges

I don't think there's coverage for many of the subtle cases, and I
found it hard to understand what the code is doing by reading it.  The
test takes 40s to run on a laptop, or 9s with --chg.

I have yet to find a description of what the files field is supposed
to be for merges. I thought it could be one of:
1. the files added/modified/removed relative to p1 (wouldn't seem
  useful, but `hg diff -c -r mergerev` has this behavior)
2. the files with filelog nodes not in either parent (i.e., what is
needed to create a bundle out of a commit)
3. the files added/removed/modified files by merge itself [1]

It's clearly not 1, because file contents merges are symmetric. It's
clearly not 2 because removed files and exec bit changes are
listed. It's also not 3 but I think it's intended to be 3 and the
differences are bugs.

Assuming 3, the test shows that, for merges, the list of files both
overapproximates and underapproximates. All the cases involve file
changes not in the filelog but in the manifest (existence of file
at revision, exec bit and file vs symlink).

I didn't look at all underapproximations, but they looked minor. The
two overapproximations are problematic though because they both cause
potentially long lists of files when merging cleanly.


[1] even what it means for the merge commit itself to change a file is
not completely trivial. A file in the merge being the same as in one
of the parent is too lax as it would consider that merges change
nothing when they revert all the changes done on one side. The
criteria used in the test and in the next commit for "merge didn't
touch a file" is:
- the parents and the merge all have the same file
- or, one parent didn't touch the file and the other parent contains
  the same file as the merge

Differential Revision: https://phab.mercurial-scm.org/D6612

setup repo
  $ hg init t
  $ cd t
  $ echo a > a
  $ hg commit -Am'add a'
  adding a
  $ hg verify
  checking changesets
  checking manifests
  crosschecking files in changesets and manifests
  checking files
  checked 1 changesets with 1 changes to 1 files
  $ 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
  checking changesets
  checking manifests
  crosschecking files in changesets and manifests
  checking files
  checked 0 changesets with 0 changes to 0 files
  $ 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)
  [255]
  $ 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
  abort: pretxncommit hook exited with status * (glob)
  [255]
  $ 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
  rolling back interrupted transaction
  couldn't read journal entry 'foo\n'!
  checking changesets
  checking manifests
  crosschecking files in changesets and manifests
  checking files
  checked 2 changesets with 2 changes to 1 files

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
  [255]

  $ 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
  [255]

  $ 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
  [255]

  $ hg verify
  checking changesets
  checking manifests
  crosschecking files in changesets and manifests
  checking files
  checked 1 changesets with 1 changes to 1 files

  $ 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
  checking changesets
  checking manifests
  crosschecking files in changesets and manifests
  checking files
  checked 2 changesets with 2 changes to 1 files

  $ cd ..