This should have been done as part of or as an immediate follow-up to
01b01d59e33f, but presumably this feature of extensions.py was
forgotten at that time.
In many cases, we don't need to cast to a str because the object will
be cast when it is eventually written.
As part of testing this, I added some code to raise exceptions when a
non-str was passed in and wasn't able to trigger it. i.e. we're already
passing str into this function everywhere, so the casting isn't
necessary.
Previously, we stored 2-tuples of text and label in a list and then
evaluated the labels when the buffer was popped. After this patch,
we evaluate the labels at write time and do a simple join when the
buffer is popped.
This patch appears to have no impact on performance, despite creating
fewer 2-tuples and having fewer strings hanging around in memory.
If detailed conflict markers are enabled and the closing quote gets truncated,
editors will often screw syntax highlighting up from that point because they'll
see an opening quote and think it's the beginning of a string.
In tests, the hashes change because the commit messages of the shelved bundles
also change.
Used a class as a namespace, and then wired up a classmethod to return
all known constraints. I'm mostly happy with this, even though it's
kind of weird for hg.
This is a first (very simple) version of the histedit base action.
It works well in common usecases like rebasing the whole stack and
spliting the stack.
I don't see any obvious edge cases - but probably there is more than one.
That's why I want to keep it behind experimental.histeditng config knob
for now. I think on knob for all new histedit behaviors is better because
we will test all of them together and testers will need to turn it on only
once to get all new nice things.
For the future 'base' action in histedit we need a verification
constraint which will not allow using this action with changes
that are currently edited.
Before we can add a 'base' action to histedit need to change verification
so that action can specify which steps of verification should run for it.
Also it's everything we need for the exec and stop actions implementation.
I thought about baking verification into each histedit action (so each
of them is responsible for verifying its constraints) but it felt wrong
because:
- every action would need to know its context (eg. the list of all other
actions)
- a lot of duplicated work will be added - each action will iterate through
all others
- the steps of the verification would need to be extracted and named anyway
in order to be reused
The verifyrules function grows too big now. I plan to refator it in one of
the next series.
Before this patch we were using the old api bookmarks.write instead of
bookmarks.recordchange at the end of rebase operations.
We move clearstatus within the transaction to make it easier for extensions
that wrap transactions operations.
Before this patch, strip was using repo._bookmarks.write.
This patch replaces this code with the recommended way of saving bookmarks
changes: repo._bookmarks.recordchange.
Before this patch we were using the old api bookmarks.write, this patches
replaces its usage by bookmarks.recordchange, the new api to record bookmark
changes.
The largefiles merge code (currently) does not handle change/delete conflicts.
So fall back to regular filemerge in that case.
Making this code handle change/delete conflicts is left as an exercise for the
future.
Currently strip works with a single bookmark,
the changes in this patch modifies the strip module
to work with a list of bookmarks
Building on this we can take a list of bookmarks as input
and remove all of them in a single go
This patch avoids unnecessary conflicts to resolve during rebase for the users
of changeset evolution.
This patch modifies rebase to skip obsolete commits with no successor.
It introduces a new rebase state 'revpruned' for these revisions that are
being skipped and a new message to inform the user of what is happening.
This feature is gated behind the config flag experimental.rebaseskipobsolete
When an obsolete commit is skipped, the output is:
note: not rebasing 7:360bbaa7d3ce "O", it has no successor
So far pullrebase function has always returned None value, no matter
what orig function returned. This behaviour made impossible for
pull to change returned value from mercurial process (it has always
ended with 0 value by default). This patch makes pullrebase returning
with returned value from orig.
4bc805f938a0 made 'bmstore.write()' transaction sensitive, to restore
original bookmarks correctly at failure of a transaction.
For example, shelve and unshelve imply steps below:
before 4bc805f938a0:
1. move active bookmark forward at internal rebasing
2. 'bmstore.write()' writes updated ones into .hg/bookmarks
3. rollback transaction to remove internal commits
4. restore updated bookmarks manually
after 4bc805f938a0:
1. move active bookmark forward at internal rebasing
2. 'bmstore.write()' doesn't write updated ones into .hg/bookmarks
(these are written into .hg/bookmarks.pending, if external hook
is spawn)
3. rollback transaction to remove internal commits
4. .hg/bookmarks should be clean, because it isn't changed while
transaction running: see (2) above
But if shelve or unshelve is executed in the repository created with
"shared bookmarks" ("hg share -B"), this doesn't work as expected,
because:
- share extension makes 'bmstore.write()' write updated bookmarks
into .hg/bookmarks of shared source repository regardless of
transaction activity, and
- intentional transaction failure at the end of shelve/unshelve
doesn't restore already updated .hg/bookmarks of shared source
This patch makes share extension wrap 'bmstore._writerepo()' instead
of 'bmstore.write()', because the former is used to actually write
bookmark changes out.
The SSH peer class accesses wireproto.commands[cmd] as part of encoding
command arguments. Previously, the wire protocol command was defined in
the clonebundles extension. If the client didn't have this extension
enabled (which it likely doesn't since it is meant as a server-side
extension), then clients attempting to clone via ssh:// would get a
crash due to a KeyError accessing wireproto.commands['clonebundles']
when cloning from a server that is advertising clone bundles.
Moving the definition of the wire protocol command to wireproto.py makes
this problem go away.
A side effect of this code move is servers will always respond to
"clonebundles" wire protocol command requests. This should be fine: the
server will return an empty response unless a clone bundles manifest
file is present and clients shouldn't call the command unless the server
is advertising the capability, which only happens if the clonebundles
extension is enabled and the manifest file exists.
Before this patch, mq was using repo._bookmarks.write.
This patch replaces this code with the recommended way of saving bookmarks
changes: repo._bookmarks.recordchange.
Before this patch, convert was using repo._bookmarks.write, a deprecated API
for saving bookmarks.
This patch changes the use of repo._bookmarks.write to
repo._bookmarks.recordchange.
Renaming local variables to be more precise, i want to store
a different list of bookmarks and it would be hard to
understand what marks represents in that change therefore
renaming it to repomarks. Renamed bookmarks(module)
to bookmarksmod as to free up bookmarks which will be
used when pluralizing bookmark.
'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.
'unexpected putlfile response: None' when an http error occurs is not very
helpful.
Instead, leave the handling of urllib2.HTTPError exceptions to other layers.
If the store somehow got corrupted, users could end up in weird situations that
were very hard to recover from or lead to propagation of the corruption.
Instead, spend the extra time checking the hash when copying to the working
directory. If it doesn't match, emit a warning, and don't put wrong content in
the working directory.
Commit of corresponding normal/largefiles pairs would only commit the standin.
That is usually fine, except if either the normal file or the standin is a
remove while the other is an add. In that case it would either give duplicate
colliding entries or lose the file.
Instead, commit both filenames if one of them is a remove.
Instead of reporting
spliced in ['82544090e14fe18091e04f1fb0f0d7991cbe6e7e'] as parents of 369fd983d9e13330e9f12d9fce820deae84ea223
report
spliced in 82544090e14fe18091e04f1fb0f0d7991cbe6e7e as parents of 369fd983d9e13330e9f12d9fce820deae84ea223
--collapse will do that rebase doesn't commit until the final commit. The lack
of a new commit would make it look like the rebase didn't contribute any
changes.
Instead, only warn about no commits when not using --collapse.
Back in June we made histedit use obsolete markers to cleanup when possible.
This was rolled back as part of bb3db0db4037 (which should have only rolled back
the --abort stuff, but rolled back everything). This caused a nasty bug when
used in conjuction with the inhibit+directaccess extensions where histedit would
leave old nodes around even after they had been squashed away.
The root of the problem is that we first clean up old nodes, and then we clean
up temp nodes. In the first pass, when we obsoleted old nodes, some would become
unobsolete because they had temp nodes on top of them, thus making them stick
around even after the histedit finished.
The fix is to A) move the temp node cleanup to be before the old node cleanup
(since they are topological on top of the old nodes), and B) use obsolete
markers instead of stripping.
There are a lot of considerations server operators need to know before
deploying clone bundles. They should be documented. So I rewrote the
extension docs to contain this information.
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
Refactoring by reduce the scope of the try catch block so that it only captures
what it needs. I could have made it smaller but another patch in the series
will add onto it.
When a user's repository is in an unfinished rebase state and they choose to
abort, at a minimum, the repo should be out of that state. We've found
situations where the user could not leave the state unless manually deleting the
rebasestate file. This fix ensures that no matter what exception may be raised
during the abort, the rebase state file will be deleted, the user will be out of
the rebase state and they can get their repository into a workable condition.
Server operators that have enabled clone bundles probably want clients
to use it. This patch introduces a feature that will insert a bundle2
"output" part that advertises the existence of the clone bundles
feature to clients that aren't using it.
The server uses the "cbattempted" argument to "getbundle" to determine
whether a client supports clone bundles and to avoid sending the message
to clients that failed the clone bundle for whatever reason.
When a user's repository is in an unfinished unshelve state and they choose to
abort, at a minimum, the repo should be out of that state. We've found
situations where the user could not leave the state unless manually deleting the
state file. This fix ensures that no matter what exception may be raised during
the abort, the shelved state file will be deleted, the user will be out of the
unshelve state and they can get their repository into a workable condition.
When Mozilla enabled Pygments on hg.mozilla.org, we got a lot of weirdly
colorized files. Upon further investigation, the hightlight extension
is first attempting a filename+content based match then falling back to a
purely content-driven detection mode in Pygments. Sounds good in theory.
Unfortunately, Pygments' content-driven detection establishes no minimum
threshold for returning a lexer. Furthermore, the detection code for
a number of languages is very liberal. For example, ActionScript 3 will
return a confidence of 0.3 (out of 1.0) if the first 1k of the file
we pass in matches the regex "\w+\s*:\s*\w"! Python matches on
"import ". It's no coincidence that a number of our extension-less files
were getting highlighted improperly.
This patch adds an option to have the highlighter not fall back to
purely content-based detection when filename+content detection failed.
This can be enabled to render unlighted text instead of taking the risk
that unknown file types are highlighted incorrectly. The old behavior is
still the default.
After rebasing a set of changes onto a public changeset and having the first one
be skipped, if you try to abort, the operation fails. This fix adds a check to
disallow the target rev into the dstates list within the abort function. This
list is checked for immutable states before the rest of abort does its thing.
As obsolescence markers can contains unknown nodes and 'allsuccessors' returns
them, we have to protect again that when looking for successors of the rebase
set in the destination.
Test have been expanded to catch that.
Accessing 'repo.changelog' have a small overhead because we double check that the
filtering did not changed. As we make multiple use of this into loops, we should
avoid doing the lookup/check every time. This also make the code tidier.
A rebase call that results in nothing to rebase might be considered successful
in some contexts. This factors out the return code from places where hg
determines that there is nothing to rebase, so an extenion might change this
return code to be something that would allow scripts to run without seeing this
as an error.
Server Name Indication (SNI) is commonly used in CDNs and other hosted
environments. Unfortunately, Python <2.7.9 does not support SNI and when
these older Python versions attempt to negotiate TLS to an SNI server,
they raise an opaque error like
"_ssl.c:507: error:14094410:SSL routines:SSL3_READ_BYTES:sslv3 alert
handshake failure."
We introduce a manifest attribute to denote the URL requires SNI and
have clients without SNI support filter these entries.
Not all clients are capable of reading every bundle. Currently, content
negotiation to ensure a server sends a client a compatible bundle
format is performed at request time. The response bundle is dynamically
generated at request time, so this works fine.
Clone bundles are statically generated *before* the request. This means
that a modern server could produce bundles that a legacy client isn't
capable of reading. Without some kind of "type hint" in the clone
bundles manifest, a client may attempt to download an incompatible
bundle. Furthermore, a client may not realize a bundle is incompatible
until it has processed part of the bundle (imagine consuming a 1 GB
changegroup bundle2 part only to discover the bundle2 part afterwards is
incompatibl). This would waste time and resources. And it isn't very
user friendly.
Clone bundle manifests thus need to advertise the *exact* format of the
hosted bundles so clients may filter out entries that they don't know
how to read. This patch introduces that mechanism.
We introduce the BUNDLESPEC attribute to declare the "bundle
specification" of the entry. Bundle specifications are parsed using
exchange.parsebundlespecification, which uses the same strings as the
"--type" argument to `hg bundle`. The supported bundle specifications
are well defined and backwards compatible.
When a client encounters a BUNDLESPEC that is invalid or unsupported, it
silently ignores the entry.
Before, when merging revisions with missing largefiles, the missing largefiles
would be fetched as a part of the merge. If that failed (for example because
the main repository temporarily was unavailable), the largefile would be left
missing. However, the next commit would abort and (seemed to) fail when
markcommitted tried to mark the standin file as normal and thus had to hash the
largefile that didn't exist. (Actually, the commit would succeed but the
largefile update that follows right after the commit transaction would abort -
quite confusing.)
To fix that, make sure that synclfdirstate only marks files as normal if they
actually exist.
Advertising that the patch are available to be pulled requires that to be true.
So we check revision availability on the remote before sending any email.
Cloning can be an expensive operation for servers because the server
generates a bundle from existing repository data at request time. For
a large repository like mozilla-central, this consumes 4+ minutes
of CPU time on the server. It also results in significant network
utilization. Multiplied by hundreds or even thousands of clients and
the ensuing load can result in difficulties scaling the Mercurial server.
Despite generation of bundles being deterministic until the next
changeset is added, the generation of bundles to service a clone request
is not cached. Each clone thus performs redundant work. This is
wasteful.
This patch introduces the "clonebundles" extension and related
client-side functionality to help alleviate this deficiency. The
client-side feature is behind an experimental flag and is not enabled by
default.
It works as follows:
1) Server operator generates a bundle and makes it available on a
server (likely HTTP).
2) Server operator defines the URL of a bundle file in a
.hg/clonebundles.manifest file.
3) Client `hg clone`ing sees the server is advertising bundle URLs.
4) Client fetches and applies the advertised bundle.
5) Client performs equivalent of `hg pull` to fetch changes made since
the bundle was created.
Essentially, the server performs the expensive work of generating a
bundle once and all subsequent clones fetch a static file from
somewhere. Scaling static file serving is a much more manageable
problem than scaling a Python application like Mercurial. Assuming your
repository grows less than 1% per day, the end result is 99+% of CPU
and network load from clones is eliminated, allowing Mercurial servers
to scale more easily. Serving static files also means data can be
transferred to clients as fast as they can consume it, rather than as
fast as servers can generate it. This makes clones faster.
Mozilla has implemented similar functionality of this patch on
hg.mozilla.org using a custom extension. We are hosting bundle files in
Amazon S3 and CloudFront (a CDN) and have successfully offloaded
>1 TB/day in data transfer from hg.mozilla.org, freeing up significant
bandwidth and CPU resources. The positive impact has been stellar and
I believe it has proved its value to be included in Mercurial core. I
feel it is important for the client-side support to be enabled in core
by default because it means that clients will get faster, more reliable
clones and will enable server operators to reduce load without
requiring any client-side configuration changes (assuming clients are
up to date, of course).
The scope of this feature is narrowly and specifically tailored to
cloning, despite "serve pulls from pre-generated bundles" being a valid
and useful feature. I would eventually like for Mercurial servers to
support transferring *all* repository data via statically hosted files.
You could imagine a server that siphons all pushed data to bundle files
and instructs clients to apply a stream of bundles to reconstruct all
repository data. This feature, while useful and powerful, is
significantly more work to implement because it requires the server
component have awareness of discovery and a mapping of which changesets
are in which files. Full, clone bundles, by contrast, are much simpler.
The wire protocol command is named "clonebundles" instead of something
more generic like "staticbundles" to leave the door open for a new, more
powerful and more generic server-side component with minimal backwards
compatibility implications. The name "bundleclone" is used by Mozilla's
extension and would cause problems since there are subtle differences
in Mozilla's extension.
Mozilla's experience with this idea has taught us that some form of
"content negotiation" is required. Not all clients will support all
bundle formats or even URLs (advanced TLS requirements, etc). To ensure
the highest uptake possible, a server needs to advertise multiple
versions of bundles and clients need to be able to choose the most
appropriate from that list one. The "attributes" in each
server-advertised entry facilitate this filtering and sorting. Their
use will become apparent in subsequent patches.
Initial inspiration and credit for the idea of cloning from static files
belongs to Augie Fackler and his "lookaside clone" extension proof of
concept.
That function is actually not returning public ancestors at all. This is
pointed by the second line of the docstring...
The bundling behavior was made correct in a5141977198d but with confusion
remaining regarding what each function was doing.
This close issue4737, because this highlight that shelve is actually -not-
bundling too much data (this was actually properly tested).
cvsps computes the parent revisions of log entries by walking the cvs log
sorted by (rcs, revision) and by iteratively maintaining a 'versions'
dictionary which maps a (rcs, branch) pair onto the last revision seen for that
pair. When log caching is on and a log cache exists, cvsps fails to set the
parent revisions of new log entries because it does not iterate over the log
cache in the parents computation. A complication is that a file rcs can change
(move to/from the attic), with respect to its value in the log cache, if the
file is removed/added back. This patch adds an iteration over the log cache to
update the rcs of cached log entries, if changed, and to properly populate the
'versions' dictionary.
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.
When an user aborts a histedit, many things could go wrong. At a minimum, after
a histedit abort failure, their repository should be out of that state. We've
found situations where the user could not exit the histedit state without
manually deleting the histedit state file. This patch ensures that if any
exception happens during an abort, the histedit statefile will be deleted so
that users are out of the histedit state and can at least manually get the repo
back to a workable condition.
When the histeditstate class instance has it's clear() method called, there is
nothing to check to see if the state file exists before deleting it. It may not
exist, which would create an exception. This patch allows clear to be called at
any time.
This will be needed for the following patch.
If a histedit is progress, the 'histedit-state' file should exist. The patch
implements a convenience function to do check if a histedit is in progress.
This method will be use in next patch in the series.
Previous patch made dirstate changes in a transaction scope "all or
nothing". Therefore, 'dirstateguard' is meaningless, if its scope is
as same as one of the related transaction.
This patch removes such meaningless 'dirstateguard' usage.
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.
patchbomb relies on the 'hg bundle' command to generate an attached bundle using
--bundle. However, while 'hg bundle' has a --type option, patchbomb did not.
This is becoming very relevant since we are about to issue bundle2 for
general-delta repository.
This was tracked as issue4863
This config allows to specify a public location where your changeset can be
found. It then include a dedicated patch header show a command to be used to
retrieve the change. See the test for example.
This is flagged as experimental because this feature is not safe until we have
more logic to test that:
- changeset actually exists on destination
- changeset is draft on destination.
As all this is experimental, bike shedding can happily happens before we remove
the experimental flag.
Before this patch, "hg unshelve" uses aborting a current transaction
to discard temporary changes while unshelving.
This assumes that dirstate changes in a transaction scope are kept
even after aborting it. But this assumption will be broken by
"transactional dirstate". See the wiki page below for detail about it.
https://mercurial.selenic.com/wiki/DirstateTransactionPlan
This patch explicitly saves shelved dirstate just before aborting
current transaction, and restore dirstate with it after aborting by
utility function '_aborttransaction()' added by previous patch.
Before this patch, "hg shelve" uses aborting a current transaction to
discard temporary changes while shelving.
This assumes that dirstate changes in a transaction scope are kept
even after aborting it. But this assumption will be broken by
"transactional dirstate". See the wiki page below for detail about it.
https://mercurial.selenic.com/wiki/DirstateTransactionPlan
This patch explicitly saves shelved dirstate just before aborting
current transaction, and restore dirstate with it after aborting by
utility function '_aborttransaction()' added by previous patch.
This patch replaces 'if tr: tr.abort()' by 'lockmod.release(tr)',
because the former is already done in '_aborttransaction()' (and the
latter has no effect), if current transaction is aborted in it
successfully. Otherwise, the latter is enough to trigger aborting.
"hg shelve" and "hg unshelve" use aborting a current transaction to
discard temporary changes while (un)shelving.
This assumes that dirstate changes in a transaction scope are kept
even after aborting it. But this assumption will be broken by
"transactional dirstate". See the wiki page below for detail about it.
https://mercurial.selenic.com/wiki/DirstateTransactionPlan
This patch adds utility function "_aborttransaction()" to abort
current transaction but keep dirstate changes for (un)shelving.
'dirstate.invalidate()' just after aborting a transaction should be
removed soon by subsequent patch, which writes or discards in-memory
dirstate changes at releasing transaction according to the result of
it.
BTW, there are some other ways below, which (seem to, at first glance)
resolve this issue. But this patch chose straightforward way for ease
of review and future refactorring.
- commit transaction at first, and then rollback it
It causes unintentional "dirty read" of running transaction to
other processes at committing it.
- use dirstateguard to save and restore shelved dirstate
After DirstateTransactionPlan, making 'dirstate.write()' write
in-memory changes into actual file requires
'transaction.writepending()' while transaction running.
It causes meaningless writing other in-memory changes out, even
though they are never referred.
In addition to it, it isn't desirable that scope of dirstateguard
and transaction intersects each other.
- get list of files changed from the parent, keep it in memory, and
emulate that changes after aborting transaction
This additional memory consumption may block aborting transaction
in large repository (on small resource environment).
Before this patch, 'bmstore.write()' always write in-memory bookmark
changes into '.hg/bookmarks' regardless of transaction activity.
If 'bmstore.write()' is invoked inside a transaction and it writes
changes into '.hg/bookmarks', then:
- original bookmarks aren't restored at failure of that transaction
This breaks "all or nothing" policy of the transaction.
BTW, "hg rollback" can restore bookmarks successfully even before
this patch, because original bookmarks are saved into
'.hg/journal.bookmarks' at the beginning of the transaction, and
it (actually renamed as '.hg/undo.bookmarks') is used by "hg
rollback".
- uncommitted bookmark changes are visible to other processes
This is a kind of "dirty read"
For example, 'rebase.rebase()' implies 'bmstore.write()', and it may
be executed inside the transaction of "hg unshelve". Then, intentional
aborting at the end of "hg unshelve" transaction doesn't restore
original bookmarks (this is obviously a bug).
This patch uses 'bmstore.recordchange()' instead of actual writing by
'bmstore._writerepo()', if any transaction is active
This patch also removes meaningless restoring bmstore explicitly at
the end of "hg shelve".
This patch doesn't choose fixing each 'bmstore.write()' callers as
like below, because writing similar code here and there is very
redundant.
before:
bmstore.write()
after:
tr = repo.currenttransaction()
if tr:
bmstore.recordchange(tr)
else:
bmstore.write()
Even though 'bmstore.write()' itself may have to be discarded by
putting bookmark operations into transaction scope, this patch chose
fixing it to implement "transactional dirstate" at first.
We will generate different changegroup if general delta is enabled so we gather
this in the lower level function. There wasn't any good reason to have it in
the main code anyway.
