Before this patch, making a commit on a local repo could move a bookmark and
both operations would not be grouped as one transaction. This patch makes both
operations part of one transaction. This is necessary to switch to the new api
to save bookmarks repo._bookmarks.recordchange if we don't want to change the
current behavior of rollback.
Dirstate change happening after the commit is done is now part of the
transaction mentioned above. This leads to a change in the expected output of
several tests.
The change to test-fncache happens because both lock are now released in the
same finally clause. The lock release is made explicitly buggy in this test.
Previously releasing lock would crash triggering release of wlock that crashes
too. Now lock release crash does not directly result in the release of wlock.
Instead wlock is released at garbage collection time and the error raised at
that time "confuses" python.
This option will make repositories created as general delta by default but will
not make Mercurial aggressively recompute deltas for all incoming bundle.
Instead, the delta contained in the bundle will be used. This will allow us to
start having general delta repositories created everywhere without triggering
massive recomputation costs for all new clients cloning from old servers.
General delta is currently controlled by a single option, we will introduce a
new one in the next changeset.
We extract the logic in a function while it is simple.
'repo.invalidate()' deletes 'filecache'-ed properties by
'filecache.__delete__()' below via 'delattr(unfiltered, k)'. But
cached objects are still kept in 'repo._filecache'.
def __delete__(self, obj):
try:
del obj.__dict__[self.name]
except KeyError:
raise AttributeError(self.name)
If 'repo' object is reused even after failure of command execution,
referring 'filecache'-ed property may reuse one kept in
'repo._filecache', even if reloading from a file is expected.
Executing command sequence on command server is a typical case of this
situation (e0a0f9ad3e4c also tried to fix this issue). For example:
1. start a command execution
2. 'changelog.delayupdate()' is invoked in a transaction scope
This replaces own 'opener' by '_divertopener()' for additional
accessing to '00changelog.i.a' (aka "pending file").
3. transaction is aborted, and command (1) execution is ended
After 'repo.invalidate()' at releasing store lock, changelog
object above (= 'opener' of it is still replaced) is deleted from
'repo.__dict__', but still kept in 'repo._filecache'.
4. start next command execution with same 'repo'
5. referring 'repo.changelog' may reuse changelog object kept in
'repo._filecache' according to timestamp of '00changelog.i'
'00changelog.i' is truncated at transaction failure (even though
this truncation is unintentional one, as described later), and
'st_mtime' of it is changed. But 'st_mtime' doesn't have enough
resolution to always detect this truncation, and invalid
changelog object kept in 'repo._filecache' is reused
occasionally.
Then, "No such file or directory" error occurs for
'00changelog.i.a', which is already removed at (3).
This patch discards objects in '_filecache' other than dirstate at
transaction failure.
Changes in 'invalidate()' can't be simplified by 'self._filecache =
{}', because 'invalidate()' should keep dirstate in 'self._filecache'
'repo.invalidate()' at "hg qpush" failure is removed in this patch,
because now it is redundant.
This patch doesn't make 'repo.invalidate()' always discard objects in
'_filecache', because 'repo.invalidate()' is invoked also at unlocking
store lock.
- "always discard objects in filecache at unlocking" may cause
serious performance problem for subsequent procedures at normal
execution
- but it is impossible to "discard objects in filecache at unlocking
only at failure", because 'releasefn' of lock can't know whether a
lock scope is terminated normally or not
BTW, using "with" statement described in PEP343 for lock may
resolve this ?
After this patch, truncation of '00changelog.i' still occurs at
transaction failure, even though newly added revisions exist only in
'00changelog.i.a' and size of '00changelog.i' isn't changed by this
truncation.
Updating 'st_mtime' of '00changelog.i' implied by this redundant
truncation also affects cache behavior as described above.
This will be fixed by dropping '00changelog.i' at aborting from the
list of files to be truncated in transaction.
This patch centralizes passing HG_PENDING to external hook process
into '_exthook()'. To make in-memory changes visible to external hook
process, this patch does:
- write (or schedule to write) in-memory dirstate changes, and
- set HG_PENDING environment variable, if:
- a transaction is running, and
- there are in-memory changes to be visible
This patch tests some commands with some hooks, because transaction
activity of a same hook differs from each other ("---": "not tested").
======== ========= ========= ============
command preupdate precommit pretxncommit
======== ========= ========= ============
unshelve o --- ---
backout x --- ---
import --- o o
qrefresh --- x o
======== ========= ========= ============
Each hooks are examined separately to prevent in-memory changes from
being visible to external process accidentally by side effect of hooks
previously invoked.
Now, 'dirstate.write(tr)' delays writing in-memory changes out, if a
transaction is running.
This may cause treating this revision as "the first bad one" at
bisecting in some cases using external hook process inside transaction
scope, because some external hooks and editor process are still
invoked without HG_PENDING and pending changes aren't visible to them.
'dirstate.write()' callers below in localrepo.py explicitly use 'None'
as 'tr', because they can assume that no transaction is running:
- just before starting transaction
- at closing transaction, or
- at unlocking wlock
This code will not currently be activated because there's no code to mark
files as driver-resolved in core. This point is also somewhat hard to plug into
from extensions.
This patch delays writing in-memory changes out, if transaction is
running.
'_getfsnow()' is defined as a function, to hook it easily for
ambiguous timestamp tests (see also fakedirstatewritetime.py)
'if tr:' code path in this patch is still disabled at this revision,
because there is no client invoking 'dirstate.write()' with repo
object.
BTW, this patch changes 'dirstate.invalidate()' semantics around
'dirstate.write()' in a transaction scope:
before:
with repo.transaction():
dirstate.CHANGE('A')
dirstate.write() # change for A is written out here
dirstate.CHANGE('B')
dirstate.invalidate() # discards only change for B
after:
with repo.transaction():
dirstate.CHANGE('A')
dirstate.write() # change for A is still kept in memory
dirstate.CHANGE('B')
dirstate.invalidate() # discards changes for A and B
Fortunately, there is no code path expecting the former, at least, in
Mercurial itself, because 'dirstateguard' was introduced to remove
such 'dirstate.invalidate()'.
'localrepository.rollback()' explicilty restores dirstate, only if at
least one of current parents of the working directory is removed at
rollbacking (a.k.a "parent-gone").
After DirstateTransactionPlan, 'dirstate.write()' will cause marking
'.hg/dirstate' as a file to be restored at rollbacking.
https://mercurial.selenic.com/wiki/DirstateTransactionPlan
Then, 'transaction.rollback()' restores '.hg/dirstate' regardless of
parents of the working directory at that time, and this causes
unexpected dirstate changes if not "parent-gone" (e.g. "hg update" to
another branch after "hg commit" or so, then "hg rollback").
To avoid such situation, this patch restores dirstate to one before
rollbacking if not "parent-gone".
before:
b1. restore dirstate explicitly, if "parent-gone"
after:
a1. save dirstate before actual rollbacking via dirstateguard
a2. restore dirstate via 'transaction.rollback()'
a3. if "parent-gone"
- discard backup (a1)
- restore dirstate from 'undo.dirstate'
a4. otherwise, restore dirstate from backup (a1)
Even though restoring dirstate at (a3) after (a2) seems redundant,
this patch keeps this existing code path, because:
- it isn't ensured that 'dirstate.write()' was invoked at least once
while transaction running
If not, '.hg/dirstate' isn't restored at (a2).
In addition to it, rude 3rd party extension invoking
'dirstate.write()' without 'repo' while transaction running (see
subsequent patches for detail) may break consistency of a file
backup-ed by transaction.
- this patch mainly focuses on changes for DirstateTransactionPlan
Restoring dirstate at (a3) itself should be cheaper enough than
rollbacking itself. Redundancy will be removed in next step.
Newly added test is almost meaningless at this point. It will be used
to detect regression while implementing delayed dirstate write out.
The home of 'Abort' is 'error' not 'util' however, a lot of code seems to be
confused about that and gives all the credit to 'util' instead of the
hardworking 'error'. In a spirit of equity, we break the cycle of injustice and
give back to 'error' the respect it deserves. And screw that 'util' poser.
For great justice.
Before this patch, in-memory dirstate changes are still kept over a
transaction scope boundary regardless of the result of it.
For "all or nothing" policy of the transaction, in-memory dirstate
changes should be:
- written out at successful closing a transaction, because
subsequent 'dirstate.invalidate()' can lose them
- discarded at failure of a transaction, because outer
'wlock.release()' or so may write them out
To discard all changes in a transaction completely, this patch also
restores '.hg/dirstate' by '.hg/journal.dirstate' at failure, because
'transaction' itself does nothing for files related to '.hg/journal.*'
in such case (therefore, renaming in this patch is safe enough).
This is a part of preparations for "transactional dirstate". See also
the wiki page below for detail about it.
https://mercurial.selenic.com/wiki/DirstateTransactionPlan
This patch also removes redundant 'dirstate.invalidate()' just before
aborting a transaction for shelve/unshelve.
Review feedback from Pierre-Yves David. A separate line of work is working to
ensure that dirstate writes are written to a separate 'pending' file while a
transaction is active. Lock inheritance currently conflicts with that, so dodge
the issue by simply preventing inheritance while a transaction is running.
Custom merge drivers aren't going to run inside a transaction, so this doesn't
affect that.
This will be useful to pass around a reference to the lock to some functions
we're going to add to scmutil. We don't want those functions to live in
localrepo to avoid bloat.
This is part of a series that will allow locks to be inherited by subprocesses
in limited circumstances.
When allowed, the parent process will pass down requisite information to the
child process by way of this environment variable.
Stream clones are a special case of clones. Clones are a special case of
pull. Most of the logic for deciding what to do at pull time is in
exchange.py. It makes sense for the stream clone determination to live
there as well.
This patch moves the calling of the stream clone code into pull(). The
checks in streamclone.canperformstreamclone() ensure that we don't
perform a stream clone unless it is possible.
A future patch will convert maybeperformstreamclone() to accept a
pullop to make it consistent with everything else in pull(). It will
also grow some functionality (in case you doubted the necessity of a 4
line function).
An upcoming patch will move the invocation of stream cloning logic to
the normal pull code path (from localrepository.clone). In preparation
for this, we teach pull() and pulloperation about whether a streaming
clone is requested.
The return logic in localrepository.clone() has been reformatted
slightly because of line length issues.
This is the last remnants of streaming clone code in localrepo.py.
This is a mostly mechanical transplant of code to a new file. Only a
rewrite of "self" to "repo" was performed. The code will be
significantly refactored in upcoming patches. So don't scrutinize it too
closely.
Upcoming patches will modernize the streaming clone code. Streaming
clone data and code kind of lives in its own world. exchange.py is
arguably the most appropriate existing location for it. However, over
a dozen patches from now it became apparent that there was a lot of code
related to streaming clones and that having it contained within its own
module would make it easier to comprehend. So, we establish
streamclone.py.
It's worth noting that streamclone.py existed a long time ago, last seen
in the 1.6 release. It was removed in 2cd3dd86758c.
The function was renamed as part of the move because its old name was
redundant with the new module name. The only other content change was
"self" was renamed to "repo" and minor grammar in the docstring was
updated.
Because _phaserevs and _phasesets cache revision numbers, they must be
invalidated if there are new commits or stripped revisions. We could do
that by calling _phasecache.invalidate(), but it wasn't simple to be
integrated with the filecache mechanism.
So for now, phasecache will be recreated after repo.invalidate() if
00changelog.i was modified before.
Because _phaserevs and _phasesets cache revision numbers, they must be
invalidated if there are new commits or stripped revisions. We could do
that by calling _phasecache.invalidate(), but it wasn't simple to be
integrated with the filecache mechanism.
So for now, phasecache will be recreated after repo.invalidate() if
00changelog.i was modified before.
Mutable default arguments are know to the state of California to cause bugs. We
just added support of None for the underlying function, so nothing else the
required.
If commit is aborted by pretxncommit hook, in-memory changelog and manifest
have entries that would be added. So they must be discarded on invalidate().
But the mechanism introduced by 071f71da2fe2 doesn't handle this case well.
It tries to mitigate the penalty of invalidate() by marking in-memory cache
as "clean" on unlock assuming that they are identical to the stored data.
But this assumption is wrong if stored data are rolled back by tr.abort().
This patch moves the hook to post-close action so that it will never be
triggered on abort.
This bug was originally reported to thg, which is only reproducible in
command-server process on unix, evolve disabled.
https://bitbucket.org/tortoisehg/thg/issues/4285/
This adds an option for delta'ing against both p1 and p2 when applying merge
revisions and picking whichever is smallest.
Some before and after stats on manifest.d size:
internal large repo:
before: 1.2 GB
after: 930 MB
mozilla-central:
before: 261 MB
after: 92 MB
Before this patch, in-memory dirstate changes aren't written out at
opening transaction, even though 'journal.dirstate' is created
directly from '.hg/dirstate'.
Therefore, subsequent 'hg rollback' uses incomplete 'undo.dirstate' to
restore dirstate, if dirstate is changed and isn't written out before
opening transaction.
In cases below, the condition "dirstate is changed and isn't written
out before opening transaction" isn't satisfied and this problem
doesn't appear:
- "wlock scope" and "transaction scope" are almost equivalent
e.g. 'commit --amend', 'import' and so on
- dirstate changes are written out before opening transaction
e.g. 'rebase' (via 'dirstateguard') and 'commit -A' (by separated
wlock scopes)
On the other hand, 'backout' may satisfy the condition above.
To make 'journal.dirstate' contain in-memory changes before opening
transaction, this patch explicitly invokes 'dirstate.write()' in
'localrepository.transaction()'.
'dirstate.write()' is placed before not "writing journal files out"
but "invoking pretxnopen hooks" for visibility of dirstate changes to
external hook processes.
BTW, in the test script, 'touch -t 200001010000' and 'hg status' are
invoked to make file 'c' surely clean in dirstate, because "clean but
unsure" files indirectly cause 'dirstate.write()' at 'repo.status()'
in 'repo.commit()' (see e1d123a2ee1f for detail) and prevents from
certainly reproducing the issue.
This allows us to use the integer representation in revset. None doesn't
work well while computing revset because revset heavily depends on and
optimized for integer revisions.
Still repo[wdirrev].rev() is None, which means the canonical form of the
working-directory revision is None.
This patch doesn't add the case for the wdirid because we can't handle short
and ambiguous identifiers here. Perhaps, the wdirid will have to be handled
in the changelog layer.
Python 2.6 introduced the "except type as instance" syntax, replacing
the "except type, instance" syntax that came before. Python 3 dropped
support for the latter syntax. Since we no longer support Python 2.4 or
2.5, we have no need to continue supporting the "except type, instance".
This patch mass rewrites the exception syntax to be Python 2.6+ and
Python 3 compatible.
This patch was produced by running `2to3 -f except -w -n .`.
