bundle2: extract logic for seeking bundle2 part into own class
Currently, unbundlepart classes support bi-directional seeking.
Most consumers of unbundlepart only ever seek forward - typically
as part of moving to the end of the bundle part so they can move
on to the next one. But regardless of the actual usage of the
part, instances maintain an index mapping offsets within the
underlying raw payload to offsets within the decoded payload.
Maintaining the mapping of offset data can be expensive in terms of
memory use. Furthermore, many bundle2 consumers don't have access
to an underlying seekable stream. This includes all compressed
bundles. So maintaining offset data when the underlying stream
can't be seeked anyway is wasteful. And since many bundle2 streams
can't be seeked, it seems like a bad idea to expose a seek API
in bundle2 parts by default. If you provide them, people will
attempt to use them.
Seekable bundle2 parts should be the exception, not the rule. This
commit starts the process dividing unbundlepart into 2 classes: a
base class that supports linear, one-time reads and a child class
that supports bi-directional seeking. In this first commit, we
split various methods and attributes out into a new
"seekableunbundlepart" class. Previous instantiators of "unbundlepart"
now instantiate "seekableunbundlepart." This preserves backwards
compatibility. The coupling between the classes is still tight:
"unbundlepart" cannot be used on its own. This will be addressed
in subsequent commits.
Differential Revision: https://phab.mercurial-scm.org/D1386
$ 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('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('proper')
> tr2 = repo.transaction('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', 'a'):
> pass
>
> @command(b'no-lock-write', [], '')
> def nolockwrite(ui, repo):
> with repo.svfs(b'fncache', 'a'):
> pass
>
> @command(b'stripintr', [], '')
> def stripintr(ui, repo):
> lo = repo.lock()
> tr = repo.transaction('foobar')
> try:
> repair.strip(repo.ui, repo, [repo['.'].node()])
> finally:
> lo.release()
> @command(b'oldanddeprecated', [], '')
> def oldanddeprecated(ui, repo):
> """test deprecation warning API"""
> def foobar(ui):
> ui.deprecwarn('foorbar is deprecated, go shopping', '42.1337')
> foobar(ui)
> @command(b'nouiwarning', [], '')
> def nouiwarning(ui, repo):
> util.nouideprecwarn('this is a test', '13.37')
> @command(b'programmingerror', [], '')
> def programmingerror(ui, repo):
> raise error.ProgrammingError('something went wrong', hint='try again')
> 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)
#if no-chg
$ 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 _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)
#else
$ 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 _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 _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/dispatch.py:* in dispatch (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
$ 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
$ 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/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)
#else
$ 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/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 _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/dispatch.py:* in dispatch (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 no-chg
$ hg blackbox -l 7
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/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 bob @cb9a9f314b8b07ba71012fcdbc544b5a4d82ff5b (5000)> oldanddeprecated --traceback exited 0 after * seconds (glob)
1970/01/01 00:00:00 bob @cb9a9f314b8b07ba71012fcdbc544b5a4d82ff5b (5000)> blackbox -l 7
#else
$ hg blackbox -l 7
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/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 _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/dispatch.py:* in dispatch (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 bob @cb9a9f314b8b07ba71012fcdbc544b5a4d82ff5b (5000)> oldanddeprecated --traceback exited 0 after * seconds (glob)
1970/01/01 00:00:00 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
** 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
** 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('this is a test', '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 registrar, configitems
>
> cmdtable = {}
> command = registrar.command(cmdtable)
>
> configtable = {}
> configitem = registrar.configitem(configtable)
>
> configitem('test', 'some', default='foo')
> configitem('test', 'dynamic', default=configitems.dynamicdefault)
> configitem('test', 'callable', default=list)
> # overwrite a core config
> configitem('ui', 'quiet', default=False)
> configitem('ui', 'interactive', default=None)
>
> @command(b'buggyconfig')
> def cmdbuggyconfig(ui, repo):
> repo.ui.config('ui', 'quiet', True)
> repo.ui.config('ui', 'interactive', False)
> repo.ui.config('test', 'some', 'bar')
> repo.ui.config('test', 'some', 'foo')
> repo.ui.config('test', 'dynamic', 'some-required-default')
> repo.ui.config('test', 'dynamic')
> repo.ui.config('test', 'callable', [])
> repo.ui.config('test', 'callable', 'foo')
> repo.ui.config('test', 'unregistered')
> repo.ui.config('unregistered', '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)
devel-warn: extension 'buggyconfig' overwrite config item 'ui.quiet' at: */mercurial/extensions.py:* (_loadextra) (glob)
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 ..