tests/test-devel-warnings.t

worker: avoid potential partial write of pickled data

Previously, the code wrote the pickled data using os.write(). However,
os.write() can write less bytes than passed to it. To trigger the problem, the
pickled data had to be larger than 2147479552 bytes on my system.

Instead, open a file object and pass it to pickle.dump(). This also has the
advantage that it doesn’t buffer the whole pickled data in memory.

Note that the opened file must be buffered because pickle doesn’t support
unbuffered streams because unbuffered streams’ write() method might write less
bytes than passed to it (like os.write()) but pickle.dump() relies on that all
bytes are written (see https://github.com/python/cpython/issues/93050).

The side effect of using a file object and a with statement is that wfd is
explicitly closed now while it seems like before it was implicitly closed by
process exit.

  $ cat << EOF > buggylocking.py
  > """A small extension that tests our developer warnings
  > """
  > 
  > from mercurial import error, registrar, repair, util
  > 
  > cmdtable = {}
  > command = registrar.command(cmdtable)
  > 
  > @command(b'buggylocking', [], '')
  > def buggylocking(ui, repo):
  >     lo = repo.lock()
  >     wl = repo.wlock()
  >     wl.release()
  >     lo.release()
  > 
  > @command(b'buggytransaction', [], '')
  > def buggylocking(ui, repo):
  >     tr = repo.transaction(b'buggy')
  >     # make sure we rollback the transaction as we don't want to rely on the__del__
  >     tr.release()
  > 
  > @command(b'properlocking', [], '')
  > def properlocking(ui, repo):
  >     """check that reentrance is fine"""
  >     wl = repo.wlock()
  >     lo = repo.lock()
  >     tr = repo.transaction(b'proper')
  >     tr2 = repo.transaction(b'proper')
  >     lo2 = repo.lock()
  >     wl2 = repo.wlock()
  >     wl2.release()
  >     lo2.release()
  >     tr2.close()
  >     tr.close()
  >     lo.release()
  >     wl.release()
  > 
  > @command(b'nowaitlocking', [], '')
  > def nowaitlocking(ui, repo):
  >     lo = repo.lock()
  >     wl = repo.wlock(wait=False)
  >     wl.release()
  >     lo.release()
  > 
  > @command(b'no-wlock-write', [], '')
  > def nowlockwrite(ui, repo):
  >     with repo.vfs(b'branch', b'a'):
  >         pass
  > 
  > @command(b'no-lock-write', [], '')
  > def nolockwrite(ui, repo):
  >     with repo.svfs(b'fncache', b'a'):
  >         pass
  > 
  > @command(b'stripintr', [], '')
  > def stripintr(ui, repo):
  >     lo = repo.lock()
  >     tr = repo.transaction(b'foobar')
  >     try:
  >         repair.strip(repo.ui, repo, [repo[b'.'].node()])
  >     finally:
  >         lo.release()
  > @command(b'oldanddeprecated', [], '')
  > def oldanddeprecated(ui, repo):
  >     """test deprecation warning API"""
  >     def foobar(ui):
  >         ui.deprecwarn(b'foorbar is deprecated, go shopping', b'42.1337')
  >     foobar(ui)
  > @command(b'nouiwarning', [], '')
  > def nouiwarning(ui, repo):
  >     util.nouideprecwarn(b'this is a test', b'13.37')
  > @command(b'programmingerror', [], '')
  > def programmingerror(ui, repo):
  >     raise error.ProgrammingError(b'something went wrong', hint=b'try again')
  > EOF

  $ cat << EOF >> $HGRCPATH
  > [extensions]
  > buggylocking=$TESTTMP/buggylocking.py
  > mock=$TESTDIR/mockblackbox.py
  > blackbox=
  > [devel]
  > all-warnings=1
  > [blackbox]
  > track = command, commandexception, commandfinish, develwarn
  > 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)
#if no-chg no-pyoxidizer
  $ hg buggylocking --traceback
  devel-warn: "wlock" acquired after "lock" at:
   */hg:* in <module> (glob) (?)
   */mercurial/dispatch.py:* in run (glob)
   */mercurial/dispatch.py:* in dispatch (glob)
   */mercurial/dispatch.py:* in _rundispatch (glob)
   */mercurial/dispatch.py:* in _runcatch (glob)
   */mercurial/dispatch.py:* in _callcatch (glob)
   */mercurial/scmutil.py* in callcatch (glob)
   */mercurial/dispatch.py:* in _runcatchfunc (glob)
   */mercurial/dispatch.py:* in _dispatch (glob)
   */mercurial/dispatch.py:* in runcommand (glob)
   */mercurial/dispatch.py:* in _runcommand (glob)
   */mercurial/dispatch.py:* in <lambda> (glob)
   */mercurial/util.py:* in check (glob)
   $TESTTMP/buggylocking.py:* in buggylocking (glob)
#endif
#if chg no-pyoxidizer
  $ hg buggylocking --traceback
  devel-warn: "wlock" acquired after "lock" at:
   */hg:* in <module> (glob) (?)
   */mercurial/dispatch.py:* in run (glob)
   */mercurial/dispatch.py:* in dispatch (glob)
   */mercurial/dispatch.py:* in _rundispatch (glob)
   */mercurial/dispatch.py:* in _runcatch (glob)
   */mercurial/dispatch.py:* in _callcatch (glob)
   */mercurial/scmutil.py:* in callcatch (glob)
   */mercurial/dispatch.py:* in _runcatchfunc (glob)
   */mercurial/dispatch.py:* in _dispatch (glob)
   */mercurial/dispatch.py:* in runcommand (glob)
   */mercurial/dispatch.py:* in _runcommand (glob)
   */mercurial/dispatch.py:* in <lambda> (glob)
   */mercurial/util.py:* in check (glob)
   */mercurial/commands.py:* in serve (glob)
   */mercurial/server.py:* in runservice (glob)
   */mercurial/commandserver.py:* in run (glob)
   */mercurial/commandserver.py:* in _mainloop (glob)
   */mercurial/commandserver.py:* in _acceptnewconnection (glob)
   */mercurial/commandserver.py:* in _runworker (glob)
   */mercurial/commandserver.py:* in _serverequest (glob)
   */mercurial/commandserver.py:* in serve (glob)
   */mercurial/commandserver.py:* in serveone (glob)
   */mercurial/chgserver.py:* in runcommand (glob)
   */mercurial/commandserver.py:* in runcommand (glob)
   */mercurial/commandserver.py:* in _dispatchcommand (glob)
   */mercurial/dispatch.py:* in dispatch (glob)
   */mercurial/dispatch.py:* in _rundispatch (glob)
   */mercurial/dispatch.py:* in _runcatch (glob)
   */mercurial/dispatch.py:* in _callcatch (glob)
   */mercurial/scmutil.py:* in callcatch (glob)
   */mercurial/dispatch.py:* in _runcatchfunc (glob)
   */mercurial/dispatch.py:* in _dispatch (glob)
   */mercurial/dispatch.py:* in runcommand (glob)
   */mercurial/dispatch.py:* in _runcommand (glob)
   */mercurial/dispatch.py:* in <lambda> (glob)
   */mercurial/util.py:* in check (glob)
   $TESTTMP/buggylocking.py:* in buggylocking (glob)
#endif
#if pyoxidizer
  $ hg buggylocking --traceback
  devel-warn: "wlock" acquired after "lock" at:
   <string>:* (glob)
   mercurial.dispatch:* in run (glob)
   mercurial.dispatch:* in dispatch (glob)
   mercurial.dispatch:* in _rundispatch (glob)
   mercurial.dispatch:* in _runcatch (glob)
   mercurial.dispatch:* in _callcatch (glob)
   mercurial.scmutil:* in callcatch (glob)
   mercurial.dispatch:* in _runcatchfunc (glob)
   mercurial.dispatch:* in _dispatch (glob)
   mercurial.dispatch:* in runcommand (glob)
   mercurial.dispatch:* in _runcommand (glob)
   mercurial.dispatch:* in <lambda> (glob)
   mercurial.util:* in check (glob)
   $TESTTMP/buggylocking.py:* in buggylocking (glob)
#endif
  $ hg properlocking
  $ hg nowaitlocking

Writing without lock

  $ hg no-wlock-write
  devel-warn: write with no wlock: "branch" at: $TESTTMP/buggylocking.py:* (nowlockwrite) (glob)

  $ hg no-lock-write
  devel-warn: write with no lock: "fncache" at: $TESTTMP/buggylocking.py:* (nolockwrite) (glob)

Stripping from a transaction

  $ echo a > a
  $ hg add a
  $ hg commit -m a
  $ hg stripintr 2>&1 | egrep -v '^(\*\*|  )'
  Traceback (most recent call last):
  *ProgrammingError: cannot strip from inside a transaction (glob)

  $ 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)

#if no-chg no-pyoxidizer
  $ 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 _rundispatch (glob)
   */mercurial/dispatch.py:* in _runcatch (glob)
   */mercurial/dispatch.py:* in _callcatch (glob)
   */mercurial/scmutil.py* in callcatch (glob)
   */mercurial/dispatch.py:* in _runcatchfunc (glob)
   */mercurial/dispatch.py:* in _dispatch (glob)
   */mercurial/dispatch.py:* in runcommand (glob)
   */mercurial/dispatch.py:* in _runcommand (glob)
   */mercurial/dispatch.py:* in <lambda> (glob)
   */mercurial/util.py:* in check (glob)
   $TESTTMP/buggylocking.py:* in oldanddeprecated (glob)
#endif
#if chg no-pyoxidizer
  $ 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 _rundispatch (glob)
   */mercurial/dispatch.py:* in _runcatch (glob)
   */mercurial/dispatch.py:* in _callcatch (glob)
   */mercurial/scmutil.py:* in callcatch (glob)
   */mercurial/dispatch.py:* in _runcatchfunc (glob)
   */mercurial/dispatch.py:* in _dispatch (glob)
   */mercurial/dispatch.py:* in runcommand (glob)
   */mercurial/dispatch.py:* in _runcommand (glob)
   */mercurial/dispatch.py:* in <lambda> (glob)
   */mercurial/util.py:* in check (glob)
   */mercurial/commands.py:* in serve (glob)
   */mercurial/server.py:* in runservice (glob)
   */mercurial/commandserver.py:* in run (glob)
   */mercurial/commandserver.py:* in _mainloop (glob)
   */mercurial/commandserver.py:* in _acceptnewconnection (glob)
   */mercurial/commandserver.py:* in _runworker (glob)
   */mercurial/commandserver.py:* in _serverequest (glob)
   */mercurial/commandserver.py:* in serve (glob)
   */mercurial/commandserver.py:* in serveone (glob)
   */mercurial/chgserver.py:* in runcommand (glob)
   */mercurial/commandserver.py:* in runcommand (glob)
   */mercurial/commandserver.py:* in _dispatchcommand (glob)
   */mercurial/dispatch.py:* in dispatch (glob)
   */mercurial/dispatch.py:* in _rundispatch (glob)
   */mercurial/dispatch.py:* in _runcatch (glob)
   */mercurial/dispatch.py:* in _callcatch (glob)
   */mercurial/scmutil.py:* in callcatch (glob)
   */mercurial/dispatch.py:* in _runcatchfunc (glob)
   */mercurial/dispatch.py:* in _dispatch (glob)
   */mercurial/dispatch.py:* in runcommand (glob)
   */mercurial/dispatch.py:* in _runcommand (glob)
   */mercurial/dispatch.py:* in <lambda> (glob)
   */mercurial/util.py:* in check (glob)
   $TESTTMP/buggylocking.py:* in oldanddeprecated (glob)
#endif
#if pyoxidizer
  $ hg oldanddeprecated --traceback
  devel-warn: foorbar is deprecated, go shopping
  (compatibility will be dropped after Mercurial-42.1337, update your code.) at:
   <string>:* (glob)
   mercurial.dispatch:* in run (glob)
   mercurial.dispatch:* in dispatch (glob)
   mercurial.dispatch:* in _rundispatch (glob)
   mercurial.dispatch:* in _runcatch (glob)
   mercurial.dispatch:* in _callcatch (glob)
   mercurial.scmutil:* in callcatch (glob)
   mercurial.dispatch:* in _runcatchfunc (glob)
   mercurial.dispatch:* in _dispatch (glob)
   mercurial.dispatch:* in runcommand (glob)
   mercurial.dispatch:* in _runcommand (glob)
   mercurial.dispatch:* in <lambda> (glob)
   mercurial.util:* in check (glob)
   $TESTTMP/buggylocking.py:* in oldanddeprecated (glob)
#endif

#if no-chg no-pyoxidizer
  $ hg blackbox -l 7
  1970-01-01 00:00:00.000 bob @cb9a9f314b8b07ba71012fcdbc544b5a4d82ff5b (5000)> oldanddeprecated
  1970-01-01 00:00:00.000 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 00:00:00.000 bob @cb9a9f314b8b07ba71012fcdbc544b5a4d82ff5b (5000)> oldanddeprecated exited 0 after * seconds (glob)
  1970-01-01 00:00:00.000 bob @cb9a9f314b8b07ba71012fcdbc544b5a4d82ff5b (5000)> oldanddeprecated --traceback
  1970-01-01 00:00:00.000 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 _rundispatch (glob)
   */mercurial/dispatch.py:* in _runcatch (glob)
   */mercurial/dispatch.py:* in _callcatch (glob)
   */mercurial/scmutil.py* in callcatch (glob)
   */mercurial/dispatch.py:* in _runcatchfunc (glob)
   */mercurial/dispatch.py:* in _dispatch (glob)
   */mercurial/dispatch.py:* in runcommand (glob)
   */mercurial/dispatch.py:* in _runcommand (glob)
   */mercurial/dispatch.py:* in <lambda> (glob)
   */mercurial/util.py:* in check (glob)
   $TESTTMP/buggylocking.py:* in oldanddeprecated (glob)
  1970-01-01 00:00:00.000 bob @cb9a9f314b8b07ba71012fcdbc544b5a4d82ff5b (5000)> oldanddeprecated --traceback exited 0 after * seconds (glob)
  1970-01-01 00:00:00.000 bob @cb9a9f314b8b07ba71012fcdbc544b5a4d82ff5b (5000)> blackbox -l 7
#endif
#if chg no-pyoxidizer
  $ hg blackbox -l 7
  1970-01-01 00:00:00.000 bob @cb9a9f314b8b07ba71012fcdbc544b5a4d82ff5b (5000)> oldanddeprecated
  1970-01-01 00:00:00.000 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 00:00:00.000 bob @cb9a9f314b8b07ba71012fcdbc544b5a4d82ff5b (5000)> oldanddeprecated exited 0 after * seconds (glob)
  1970-01-01 00:00:00.000 bob @cb9a9f314b8b07ba71012fcdbc544b5a4d82ff5b (5000)> oldanddeprecated --traceback
  1970-01-01 00:00:00.000 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 _rundispatch (glob)
   */mercurial/dispatch.py:* in _runcatch (glob)
   */mercurial/dispatch.py:* in _callcatch (glob)
   */mercurial/scmutil.py:* in callcatch (glob)
   */mercurial/dispatch.py:* in _runcatchfunc (glob)
   */mercurial/dispatch.py:* in _dispatch (glob)
   */mercurial/dispatch.py:* in runcommand (glob)
   */mercurial/dispatch.py:* in _runcommand (glob)
   */mercurial/dispatch.py:* in <lambda> (glob)
   */mercurial/util.py:* in check (glob)
   */mercurial/commands.py:* in serve (glob)
   */mercurial/server.py:* in runservice (glob)
   */mercurial/commandserver.py:* in run (glob)
   */mercurial/commandserver.py:* in _mainloop (glob)
   */mercurial/commandserver.py:* in _acceptnewconnection (glob)
   */mercurial/commandserver.py:* in _runworker (glob)
   */mercurial/commandserver.py:* in _serverequest (glob)
   */mercurial/commandserver.py:* in serve (glob)
   */mercurial/commandserver.py:* in serveone (glob)
   */mercurial/chgserver.py:* in runcommand (glob)
   */mercurial/commandserver.py:* in runcommand (glob)
   */mercurial/commandserver.py:* in _dispatchcommand (glob)
   */mercurial/dispatch.py:* in dispatch (glob)
   */mercurial/dispatch.py:* in _rundispatch (glob)
   */mercurial/dispatch.py:* in _runcatch (glob)
   */mercurial/dispatch.py:* in _callcatch (glob)
   */mercurial/scmutil.py:* in callcatch (glob)
   */mercurial/dispatch.py:* in _runcatchfunc (glob)
   */mercurial/dispatch.py:* in _dispatch (glob)
   */mercurial/dispatch.py:* in runcommand (glob)
   */mercurial/dispatch.py:* in _runcommand (glob)
   */mercurial/dispatch.py:* in <lambda> (glob)
   */mercurial/util.py:* in check (glob)
   $TESTTMP/buggylocking.py:* in oldanddeprecated (glob)
  1970-01-01 00:00:00.000 bob @cb9a9f314b8b07ba71012fcdbc544b5a4d82ff5b (5000)> oldanddeprecated --traceback exited 0 after * seconds (glob)
  1970-01-01 00:00:00.000 bob @cb9a9f314b8b07ba71012fcdbc544b5a4d82ff5b (5000)> blackbox -l 7
#endif
#if pyoxidizer
  $ hg blackbox -l 7
  1970-01-01 00:00:00.000 bob @cb9a9f314b8b07ba71012fcdbc544b5a4d82ff5b (5000)> oldanddeprecated
  1970-01-01 00:00:00.000 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 00:00:00.000 bob @cb9a9f314b8b07ba71012fcdbc544b5a4d82ff5b (5000)> oldanddeprecated exited 0 after * seconds (glob)
  1970-01-01 00:00:00.000 bob @cb9a9f314b8b07ba71012fcdbc544b5a4d82ff5b (5000)> oldanddeprecated --traceback
  1970-01-01 00:00:00.000 bob @cb9a9f314b8b07ba71012fcdbc544b5a4d82ff5b (5000)> devel-warn: foorbar is deprecated, go shopping
  (compatibility will be dropped after Mercurial-42.1337, update your code.) at:
   <string>:* in <module> (glob)
   mercurial.dispatch:* in run (glob)
   mercurial.dispatch:* in dispatch (glob)
   mercurial.dispatch:* in _rundispatch (glob)
   mercurial.dispatch:* in _runcatch (glob)
   mercurial.dispatch:* in _callcatch (glob)
   mercurial.scmutil* in callcatch (glob)
   mercurial.dispatch:* in _runcatchfunc (glob)
   mercurial.dispatch:* in _dispatch (glob)
   mercurial.dispatch:* in runcommand (glob)
   mercurial.dispatch:* in _runcommand (glob)
   mercurial.dispatch:* in <lambda> (glob)
   mercurial.util:* in check (glob)
   $TESTTMP/buggylocking.py:* in oldanddeprecated (glob)
  1970-01-01 00:00:00.000 bob @cb9a9f314b8b07ba71012fcdbc544b5a4d82ff5b (5000)> oldanddeprecated --traceback exited 0 after * seconds (glob)
  1970-01-01 00:00:00.000 bob @cb9a9f314b8b07ba71012fcdbc544b5a4d82ff5b (5000)> blackbox -l 7
#endif

Test programming error failure:

  $ hg buggytransaction 2>&1 | egrep -v '^  '
  ** Unknown exception encountered with possibly-broken third-party extension "buggylocking" (version N/A)
  ** 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)
  ** ProgrammingError: transaction requires locking
  Traceback (most recent call last):
  *ProgrammingError: transaction requires locking (glob)

  $ hg programmingerror 2>&1 | egrep -v '^  '
  ** Unknown exception encountered with possibly-broken third-party extension "buggylocking" (version N/A)
  ** 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)
  ** ProgrammingError: something went wrong
  ** (try again)
  Traceback (most recent call last):
  *ProgrammingError: something went wrong (glob)

Old style deprecation warning

  $ hg nouiwarning
  $TESTTMP/buggylocking.py:*: DeprecationWarning: this is a test (glob)
  (compatibility will be dropped after Mercurial-13.37, update your code.)
    util.nouideprecwarn(b'this is a test', b'13.37')

(disabled outside of test run)

  $ HGEMITWARNINGS= hg nouiwarning

Test warning on config option access and registration

  $ cat << EOF > ${TESTTMP}/buggyconfig.py
  > """A small extension that tests our developer warnings for config"""
  > 
  > from mercurial import configitems, registrar
  > 
  > cmdtable = {}
  > command = registrar.command(cmdtable)
  > 
  > configtable = {}
  > configitem = registrar.configitem(configtable)
  > 
  > configitem(b'test', b'some', default=b'foo')
  > configitem(b'test', b'dynamic', default=configitems.dynamicdefault)
  > configitem(b'test', b'callable', default=list)
  > # overwrite a core config
  > configitem(b'ui', b'quiet', default=False)
  > configitem(b'ui', b'interactive', default=None)
  > 
  > @command(b'buggyconfig')
  > def cmdbuggyconfig(ui, repo):
  >     repo.ui.config(b'ui', b'quiet', True)
  >     repo.ui.config(b'ui', b'interactive', False)
  >     repo.ui.config(b'test', b'some', b'bar')
  >     repo.ui.config(b'test', b'some', b'foo')
  >     repo.ui.config(b'test', b'dynamic', b'some-required-default')
  >     repo.ui.config(b'test', b'dynamic')
  >     repo.ui.config(b'test', b'callable', [])
  >     repo.ui.config(b'test', b'callable', b'foo')
  >     repo.ui.config(b'test', b'unregistered')
  >     repo.ui.config(b'unregistered', b'unregistered')
  > EOF

  $ hg --config "extensions.buggyconfig=${TESTTMP}/buggyconfig.py" buggyconfig
  devel-warn: extension 'buggyconfig' overwrite config item 'ui.interactive' at: */mercurial/extensions.py:* (_loadextra) (glob) (no-pyoxidizer !)
  devel-warn: extension 'buggyconfig' overwrite config item 'ui.quiet' at: */mercurial/extensions.py:* (_loadextra) (glob) (no-pyoxidizer !)
  devel-warn: extension 'buggyconfig' overwrite config item 'ui.interactive' at: mercurial.extensions:* (_loadextra) (glob) (pyoxidizer !)
  devel-warn: extension 'buggyconfig' overwrite config item 'ui.quiet' at: mercurial.extensions:* (_loadextra) (glob) (pyoxidizer !)
  devel-warn: specifying a mismatched default value for a registered config item: 'ui.quiet' 'True' at: $TESTTMP/buggyconfig.py:* (cmdbuggyconfig) (glob)
  devel-warn: specifying a mismatched default value for a registered config item: 'ui.interactive' 'False' at: $TESTTMP/buggyconfig.py:* (cmdbuggyconfig) (glob)
  devel-warn: specifying a mismatched default value for a registered config item: 'test.some' 'bar' at: $TESTTMP/buggyconfig.py:* (cmdbuggyconfig) (glob)
  devel-warn: config item requires an explicit default value: 'test.dynamic' at: $TESTTMP/buggyconfig.py:* (cmdbuggyconfig) (glob)
  devel-warn: specifying a mismatched default value for a registered config item: 'test.callable' 'foo' at: $TESTTMP/buggyconfig.py:* (cmdbuggyconfig) (glob)
  devel-warn: accessing unregistered config item: 'test.unregistered' at: $TESTTMP/buggyconfig.py:* (cmdbuggyconfig) (glob)
  devel-warn: accessing unregistered config item: 'unregistered.unregistered' at: $TESTTMP/buggyconfig.py:* (cmdbuggyconfig) (glob)

  $ cd ..