Mercurial > hg
view tests/test-parseindex.t @ 33289:abd7dedbaa36
sparse: vendor Facebook-developed extension
Facebook has developed an extension to enable "sparse" checkouts -
a working directory with a subset of files. This feature is a critical
component in enabling repositories to scale to infinite number of
files while retaining reasonable performance. It's worth noting
that sparse checkout is only one possible solution to this problem:
another is virtual filesystems that realize files on first access.
But given that virtual filesystems may not be accessible to all
users, sparse checkout is necessary as a fallback.
Per mailing list discussion at
https://www.mercurial-scm.org/pipermail/mercurial-devel/2017-March/095868.html
we want to add sparse checkout to the Mercurial distribution via
roughly the following mechanism:
1. Vendor extension as-is with minimal modifications (this patch)
2. Refactor extension so it is more clearly experimental and inline
with Mercurial practices
3. Move code from extension into core where possible
4. Drop experimental labeling and/or move feature into core
after sign-off from narrow clone feature owners
This commit essentially copies the sparse extension and tests
from revision 71e0a2aeca92a4078fe1b8c76e32c88ff1929737 of the
https://bitbucket.org/facebook/hg-experimental repository.
A list of modifications made as part of vendoring is as follows:
* "EXPERIMENTAL" added to module docstring
* Imports were changed to match Mercurial style conventions
* "testedwith" value was updated to core Mercurial special value and
comment boilerplate was inserted
* A "clone_sparse" function was renamed to "clonesparse" to appease
the style checker
* Paths to the sparse extension in tests reflect built-in location
* test-sparse-extensions.t was renamed to test-sparse-fsmonitor.t
and references to "simplecache" were removed. The test always skips
because it isn't trivial to run it given the way we currently run
fsmonitor tests
* A double empty line was removed from test-sparse-profiles.t
There are aspects of the added code that are obviously not ideal.
The goal is to make a minimal number of modifications as part of
the vendoring to make it easier to track changes from the original
implementation. Refactoring will occur in subsequent patches.
author | Gregory Szorc <gregory.szorc@gmail.com> |
---|---|
date | Sat, 01 Jul 2017 10:43:29 -0700 |
parents | 8e6f4939a69a |
children | c839bbee1e13 |
line wrap: on
line source
revlog.parseindex must be able to parse the index file even if an index entry is split between two 64k blocks. The ideal test would be to create an index file with inline data where 64k < size < 64k + 64 (64k is the size of the read buffer, 64 is the size of an index entry) and with an index entry starting right before the 64k block boundary, and try to read it. We approximate that by reducing the read buffer to 1 byte. $ hg init a $ cd a $ echo abc > foo $ hg add foo $ hg commit -m 'add foo' $ echo >> foo $ hg commit -m 'change foo' $ hg log -r 0: changeset: 0:7c31755bf9b5 user: test date: Thu Jan 01 00:00:00 1970 +0000 summary: add foo changeset: 1:26333235a41c tag: tip user: test date: Thu Jan 01 00:00:00 1970 +0000 summary: change foo $ cat >> test.py << EOF > from mercurial import changelog, vfs > from mercurial.node import * > > class singlebyteread(object): > def __init__(self, real): > self.real = real > > def read(self, size=-1): > if size == 65536: > size = 1 > return self.real.read(size) > > def __getattr__(self, key): > return getattr(self.real, key) > > def opener(*args): > o = vfs.vfs(*args) > def wrapper(*a): > f = o(*a) > return singlebyteread(f) > return wrapper > > cl = changelog.changelog(opener('.hg/store')) > print len(cl), 'revisions:' > for r in cl: > print short(cl.node(r)) > EOF $ $PYTHON test.py 2 revisions: 7c31755bf9b5 26333235a41c $ cd .. #if no-pure Test SEGV caused by bad revision passed to reachableroots() (issue4775): $ cd a $ $PYTHON <<EOF > from mercurial import changelog, vfs > cl = changelog.changelog(vfs.vfs('.hg/store')) > print 'good heads:' > for head in [0, len(cl) - 1, -1]: > print'%s: %r' % (head, cl.reachableroots(0, [head], [0])) > print 'bad heads:' > for head in [len(cl), 10000, -2, -10000, None]: > print '%s:' % head, > try: > cl.reachableroots(0, [head], [0]) > print 'uncaught buffer overflow?' > except (IndexError, TypeError) as inst: > print inst > print 'good roots:' > for root in [0, len(cl) - 1, -1]: > print '%s: %r' % (root, cl.reachableroots(root, [len(cl) - 1], [root])) > print 'out-of-range roots are ignored:' > for root in [len(cl), 10000, -2, -10000]: > print '%s: %r' % (root, cl.reachableroots(root, [len(cl) - 1], [root])) > print 'bad roots:' > for root in [None]: > print '%s:' % root, > try: > cl.reachableroots(root, [len(cl) - 1], [root]) > print 'uncaught error?' > except TypeError as inst: > print inst > EOF good heads: 0: [0] 1: [0] -1: [] bad heads: 2: head out of range 10000: head out of range -2: head out of range -10000: head out of range None: an integer is required good roots: 0: [0] 1: [1] -1: [-1] out-of-range roots are ignored: 2: [] 10000: [] -2: [] -10000: [] bad roots: None: an integer is required $ cd .. Test corrupted p1/p2 fields that could cause SEGV at parsers.c: $ mkdir invalidparent $ cd invalidparent $ hg clone --pull -q --config phases.publish=False ../a limit $ hg clone --pull -q --config phases.publish=False ../a segv $ rm -R limit/.hg/cache segv/.hg/cache $ $PYTHON <<EOF > data = open("limit/.hg/store/00changelog.i", "rb").read() > for n, p in [('limit', '\0\0\0\x02'), ('segv', '\0\x01\0\0')]: > # corrupt p1 at rev0 and p2 at rev1 > d = data[:24] + p + data[28:127 + 28] + p + data[127 + 32:] > open(n + "/.hg/store/00changelog.i", "wb").write(d) > EOF $ hg debugindex -f1 limit/.hg/store/00changelog.i rev flag offset length size base link p1 p2 nodeid 0 0000 0 63 62 0 0 2 -1 7c31755bf9b5 1 0000 63 66 65 1 1 0 2 26333235a41c $ hg debugindex -f1 segv/.hg/store/00changelog.i rev flag offset length size base link p1 p2 nodeid 0 0000 0 63 62 0 0 65536 -1 7c31755bf9b5 1 0000 63 66 65 1 1 0 65536 26333235a41c $ cat <<EOF > test.py > import sys > from mercurial import changelog, vfs > cl = changelog.changelog(vfs.vfs(sys.argv[1])) > n0, n1 = cl.node(0), cl.node(1) > ops = [ > ('reachableroots', > lambda: cl.index.reachableroots2(0, [1], [0], False)), > ('compute_phases_map_sets', lambda: cl.computephases([[0], []])), > ('index_headrevs', lambda: cl.headrevs()), > ('find_gca_candidates', lambda: cl.commonancestorsheads(n0, n1)), > ('find_deepest', lambda: cl.ancestor(n0, n1)), > ] > for l, f in ops: > print l + ':', > try: > f() > print 'uncaught buffer overflow?' > except ValueError, inst: > print inst > EOF $ $PYTHON test.py limit/.hg/store reachableroots: parent out of range compute_phases_map_sets: parent out of range index_headrevs: parent out of range find_gca_candidates: parent out of range find_deepest: parent out of range $ $PYTHON test.py segv/.hg/store reachableroots: parent out of range compute_phases_map_sets: parent out of range index_headrevs: parent out of range find_gca_candidates: parent out of range find_deepest: parent out of range $ cd .. #endif