view tests/test-devel-warnings.t @ 29859:a1092e2d70a3

help: internals topic for wire protocol

The Mercurial wire protocol is under-documented. This includes a lack
of source docstrings and comments as well as pages on the official
wiki.

This patch adds the beginnings of "internals" documentation on the
wire protocol.

The documentation should have nearly complete coverage on the
lower-level parts of the protocol, such as the different transport
mechanims, how commands and arguments are sent, capabilities, and,
of course, the commands themselves.

As part of writing this documentation, I discovered a number of
deficiencies in the protocol and bugs in the implementation. I've
started sending patches for some of the issues. I hope to send a lot
more.

This patch starts with the scaffolding for a new internals page.

  $ 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 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)
  $ 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 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)
  $ 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 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 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 ..