Previously in the worst case we iterated the files in matcher twice and
had a method only for this, which reimplemented logic in subdirmatchers
constructor. So we replaced the method with a subdirmatcher.files() call.
At 9069882b46bf, we had to optimize a parsed tree to resolve x^:y ambiguity.
Since we've moved the resolution of x^:y to parse(), we no longer have to call
optimize(). Therefore, (x:y) can be taken as a single expression, not an odd
range expression x:y.
This was breaking my ability to use treemanifests in bundlerepos, and
was deeply mysterious. We should probably just make the options
property a formal part of the vfs API, and make it a required
construction parameter. Sadly, I don't have time to dive into that
refactor right now.
I can never remember the differences between the various revset
APIs. I can never remember that scmutil.revrange() is the one I
want to use from user-facing commands.
Add some documentation to clarify this.
While we're here, the argument name for revrange() is changed to
"specs" because that's what it actually is.
To make it easier to patch the wrapped function, make it possible to access the
filecache descriptor directly on the class (rather than have to use
ClassObject.__dict__['attributename']). Returning `self` when the first
argument to `__get__` is `None` makes the descriptor behave the same way
`property` objects do.
All versions of Python we support or hope to support make the hash
functions available in the same way under the same name, so we may as
well drop the util forwards.
In some cases below, renaming from backup is used to restore original
contents of a file. If renaming keeps ctime, mtime and size of a file,
restoring is overlooked, and old contents cached before restoring
isn't invalidated as expected.
- failure of transaction before closing (only from '.hg/journal.dirstate')
- rollback of previous transaction (from '.hg/undo.*')
- failure in dirstateguard scope (from '.hg/dirstate.SUFFIX')
To avoid such problem, this patch makes vfs.rename() avoid ambiguity
of file stat, if needed.
Ambiguity check is executed, only if:
- checkambig=True is specified (not all renaming needs ambiguity check), and
- destination file exists before renaming
This patch is a part of preparation for "Exact Cache Validation Plan":
https://www.mercurial-scm.org/wiki/ExactCacheValidationPlan
Update makedirs() to ignore EEXIST in case someone else has already created the
directory in question. Previously the ensuredirs() function existed, and was
nearly identical to makedirs() except that it fixed this race. Unfortunately
ensuredirs() was only used in 3 places, and most code uses the racy makedirs()
function. This fixes makedirs() to be non-racy, and replaces calls to
ensuredirs() with makedirs().
In particular, mercurial.scmutil.origpath() used the racy makedirs() code,
which could cause failures during "hg update" as it tried to create backup
directories.
This does slightly change the behavior of call sites using ensuredirs():
previously ensuredirs() would throw EEXIST if the path existed but was a
regular file instead of a directory. It did this by explicitly checking
os.path.isdir() after getting EEXIST. The makedirs() code did not do this and
swallowed all EEXIST errors. I kept the makedirs() behavior, since it seemed
preferable to avoid the extra stat call in the common case where this directory
already exists. If the path does happen to be a file, the caller will almost
certainly fail with an ENOTDIR error shortly afterwards anyway. I checked
the 3 existing call sites of ensuredirs(), and this seems to be the case for
them.
Closing files that have been appended to is relatively slow on
Windows/NTFS. This makes several Mercurial operations slower on
Windows.
The workaround to this issue is conceptually simple: use multiple
threads for I/O. Unfortunately, Python doesn't scale well to multiple
threads because of the GIL. And, refactoring our code to use threads
everywhere would be a huge undertaking. So, we decide to tackle this
problem by starting small: establishing a thread pool for closing
files.
This patch establishes a mechanism for closing file handles on separate
threads. The coordinator object is basically a queue of file handles to
operate on and a thread pool consuming from the queue.
When files are opened through the VFS layer, the caller can specify
that delay closing is allowed.
A proxy class for file handles has been added. We must use a proxy
because it isn't possible to modify __class__ on built-in types. This
adds some overhead. But as future patches will show, this overhead
is cancelled out by the benefit of closing file handles on background
threads.
Now that we dropped support for Python 2.4, we are able to use context
managers. Let's replace the try..finally pattern in scmutil.py with
context managers, which close files automatically when the context
manager is exited.
There should be no change in behavior with this patch.
Why convert to context managers if nothing is broken? I'm working on
closing file handles in background threads to improve performance on
Windows. As part of this, I realized there could be some future issues
if the background file closing code isn't designed with context
managers in mind. So, I'd like to switch some code to context managers
so I can design an API that works with context managers.
Previously, we were using Python's native 'os.path.isfile' method which follows
symlinks. In this case, since we're operating on repo contents, we don't want
to follow symlinks.
There's a behaviour change here, as shown by the second part of the added test.
Consider a symlink 'f' pointing to a file containing 'abc'. If we try and
replace it with a file with contents 'abc', previously we would have let it
though. Now we don't. Although this breaks naive inspection with tools like
'cat' and 'diff', on balance I believe this is the right change.
When using 'extdiff --patch' to check the changes in a rebase, 'precursors(x)'
evaluated to an empty set because I forgot the --hidden flag, so the other
revision was used as the replacement for the empty set. The result was the
patch for the other revision was diffed against itself, and the tool saying
there were no differences. That's misleading since the expected diff args were
silently changed, so it's better to bail out.
The other uses of scmutil.revpair() are commands.diff and commands.status, and
it doesn't make sense to allow an empty revision there either. The code here
was suggested by Yuya Nishihara.
Since we have pushed back the performance issue related to general delta behind
another configuration (Still off by default), we can safely create new
repository with general delta support. As client are compatible with it since
Mercurial 1.9 (4.5 years ago) I do no expect any significant compatibility
issues.
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.
This is part of a series that will allow locks to be inherited by subprocesses
in limited circumstances.
In the future, we'll call this for custom merge drivers.
This is part of a series that will allow locks to be inherited by subprocesses
in limited circumstances.
In an upcoming patch, we'll add an API for the wlock to be inherited.
Mutable default arguments are know to the state of California to cause bugs. We
added support for None in the underlying function in the parent commit.
therefore we do not need to do anything but passing None.
The odd-range hack was introduced by 9afcfbca1710 for backward compatibility,
but it was too widely applied. I've checked cmdutil.revpair() at 1.6, and
found that ".:", ":0" and ":" are also handled as pairs. So let's enable the
hack only for "x:y", "x:", "y:" and ":".
test-revset.t is updated because "tip^::tip^ or tip^" shouldn't be taken as
an odd range. This patch adds "tip^:tip^" instead.
This patch is written for the default branch because parse() of the stable
branch lacks compatibility hack for "foo+bar" tag. If we want to mitigate the
issue in stable, we can add something like "and '::' in revs[0]".
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.
Now revset can parse nullary ":" operator and existing "foo+bar" tags, we
don't need the old-style parser.
This means scmutil.revsingle(), revpair() and revrange() no longer accept
a binary nodeid. An integer revision is still allowed as it isn't ambiguous.
Because we defined the working-directory revision is INT_MAX, it makes sense
that "hg log -r 'wdir()'" displays the "parent:" field. This is the same for
two revisions that are semantically contiguous but the intermediate revisions
are hidden.
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 .`.
