transaction: turn lack of locking into a hard failure (API)
We have been warning about transactions without locks for about a year (and
three releases), third party extensions had a fair grace period to fix their
code, we are moving lack of locking to a hard failure in order to protect users
against repository corruption.
$ cat << EOF > buggylocking.py
> """A small extension that tests our developer warnings
> """
>
> from mercurial import cmdutil, repair, revset
>
> cmdtable = {}
> command = cmdutil.command(cmdtable)
>
> @command('buggylocking', [], '')
> def buggylocking(ui, repo):
> lo = repo.lock()
> wl = repo.wlock()
> wl.release()
> lo.release()
>
> @command('buggytransaction', [], '')
> def buggylocking(ui, repo):
> tr = repo.transaction('buggy')
> # make sure we rollback the transaction as we don't want to rely on the__del__
> tr.release()
>
> @command('properlocking', [], '')
> def properlocking(ui, repo):
> """check that reentrance is fine"""
> wl = repo.wlock()
> lo = repo.lock()
> tr = repo.transaction('proper')
> tr2 = repo.transaction('proper')
> lo2 = repo.lock()
> wl2 = repo.wlock()
> wl2.release()
> lo2.release()
> tr2.close()
> tr.close()
> lo.release()
> wl.release()
>
> @command('nowaitlocking', [], '')
> def nowaitlocking(ui, repo):
> lo = repo.lock()
> wl = repo.wlock(wait=False)
> wl.release()
> lo.release()
>
> @command('stripintr', [], '')
> def stripintr(ui, repo):
> lo = repo.lock()
> tr = repo.transaction('foobar')
> try:
> repair.strip(repo.ui, repo, [repo['.'].node()])
> finally:
> lo.release()
> @command('oldanddeprecated', [], '')
> def oldanddeprecated(ui, repo):
> """test deprecation warning API"""
> def foobar(ui):
> ui.deprecwarn('foorbar is deprecated, go shopping', '42.1337')
> foobar(ui)
>
> def oldstylerevset(repo, subset, x):
> return list(subset)
>
> revset.symbols['oldstyle'] = oldstylerevset
> EOF
$ cat << EOF >> $HGRCPATH
> [extensions]
> buggylocking=$TESTTMP/buggylocking.py
> mock=$TESTDIR/mockblackbox.py
> blackbox=
> [devel]
> all-warnings=1
> EOF
$ hg init lock-checker
$ cd lock-checker
$ hg buggylocking
devel-warn: "wlock" acquired after "lock" at: $TESTTMP/buggylocking.py:* (buggylocking) (glob)
$ cat << EOF >> $HGRCPATH
> [devel]
> all=0
> check-locks=1
> EOF
$ hg buggylocking
devel-warn: "wlock" acquired after "lock" at: $TESTTMP/buggylocking.py:* (buggylocking) (glob)
$ hg buggylocking --traceback
devel-warn: "wlock" acquired after "lock" at:
*/hg:* in * (glob)
*/mercurial/dispatch.py:* in run (glob)
*/mercurial/dispatch.py:* in dispatch (glob)
*/mercurial/dispatch.py:* in _runcatch (glob)
*/mercurial/dispatch.py:* in _dispatch (glob)
*/mercurial/dispatch.py:* in runcommand (glob)
*/mercurial/dispatch.py:* in _runcommand (glob)
*/mercurial/dispatch.py:* in checkargs (glob)
*/mercurial/dispatch.py:* in <lambda> (glob)
*/mercurial/util.py:* in check (glob)
$TESTTMP/buggylocking.py:* in buggylocking (glob)
$ hg properlocking
$ hg nowaitlocking
$ echo a > a
$ hg add a
$ hg commit -m a
$ hg stripintr
saved backup bundle to $TESTTMP/lock-checker/.hg/strip-backup/*-backup.hg (glob)
abort: programming error: cannot strip from inside a transaction
(contact your extension maintainer)
[255]
$ hg log -r "oldstyle()" -T '{rev}\n'
devel-warn: revset "oldstyle" uses list instead of smartset
(compatibility will be dropped after Mercurial-3.9, update your code.) at: *mercurial/revset.py:* (mfunc) (glob)
0
$ hg oldanddeprecated
devel-warn: foorbar is deprecated, go shopping
(compatibility will be dropped after Mercurial-42.1337, update your code.) at: $TESTTMP/buggylocking.py:* (oldanddeprecated) (glob)
$ hg oldanddeprecated --traceback
devel-warn: foorbar is deprecated, go shopping
(compatibility will be dropped after Mercurial-42.1337, update your code.) at:
*/hg:* in <module> (glob)
*/mercurial/dispatch.py:* in run (glob)
*/mercurial/dispatch.py:* in dispatch (glob)
*/mercurial/dispatch.py:* in _runcatch (glob)
*/mercurial/dispatch.py:* in _dispatch (glob)
*/mercurial/dispatch.py:* in runcommand (glob)
*/mercurial/dispatch.py:* in _runcommand (glob)
*/mercurial/dispatch.py:* in checkargs (glob)
*/mercurial/dispatch.py:* in <lambda> (glob)
*/mercurial/util.py:* in check (glob)
$TESTTMP/buggylocking.py:* in oldanddeprecated (glob)
$ hg blackbox -l 9
1970/01/01 00:00:00 bob @cb9a9f314b8b07ba71012fcdbc544b5a4d82ff5b (5000)> devel-warn: revset "oldstyle" uses list instead of smartset
(compatibility will be dropped after Mercurial-3.9, update your code.) at: *mercurial/revset.py:* (mfunc) (glob)
1970/01/01 00:00:00 bob @cb9a9f314b8b07ba71012fcdbc544b5a4d82ff5b (5000)> log -r oldstyle() -T {rev}\n exited 0 after * seconds (glob)
1970/01/01 00:00:00 bob @cb9a9f314b8b07ba71012fcdbc544b5a4d82ff5b (5000)> oldanddeprecated
1970/01/01 00:00:00 bob @cb9a9f314b8b07ba71012fcdbc544b5a4d82ff5b (5000)> devel-warn: foorbar is deprecated, go shopping
(compatibility will be dropped after Mercurial-42.1337, update your code.) at: $TESTTMP/buggylocking.py:* (oldanddeprecated) (glob)
1970/01/01 00:00:00 bob @cb9a9f314b8b07ba71012fcdbc544b5a4d82ff5b (5000)> oldanddeprecated exited 0 after * seconds (glob)
1970/01/01 00:00:00 bob @cb9a9f314b8b07ba71012fcdbc544b5a4d82ff5b (5000)> oldanddeprecated --traceback
1970/01/01 00:00:00 bob @cb9a9f314b8b07ba71012fcdbc544b5a4d82ff5b (5000)> devel-warn: foorbar is deprecated, go shopping
(compatibility will be dropped after Mercurial-42.1337, update your code.) at:
*/hg:* in <module> (glob)
*/mercurial/dispatch.py:* in run (glob)
*/mercurial/dispatch.py:* in dispatch (glob)
*/mercurial/dispatch.py:* in _runcatch (glob)
*/mercurial/dispatch.py:* in _dispatch (glob)
*/mercurial/dispatch.py:* in runcommand (glob)
*/mercurial/dispatch.py:* in _runcommand (glob)
*/mercurial/dispatch.py:* in checkargs (glob)
*/mercurial/dispatch.py:* in <lambda> (glob)
*/mercurial/util.py:* in check (glob)
$TESTTMP/buggylocking.py:* in oldanddeprecated (glob)
1970/01/01 00:00:00 bob @cb9a9f314b8b07ba71012fcdbc544b5a4d82ff5b (5000)> oldanddeprecated --traceback exited 0 after * seconds (glob)
1970/01/01 00:00:00 bob @cb9a9f314b8b07ba71012fcdbc544b5a4d82ff5b (5000)> blackbox -l 9
Test programming error failure:
$ hg buggytransaction 2>&1 | egrep -v '^ '
** Unknown exception encountered with possibly-broken third-party extension buggylocking
** which supports versions unknown of Mercurial.
** Please disable buggylocking and try your action again.
** If that fixes the bug please report it to the extension author.
** Python * (glob)
** Mercurial Distributed SCM (*) (glob)
** Extensions loaded: * (glob)
Traceback (most recent call last):
RuntimeError: programming error: transaction requires locking
$ cd ..