tests/test-manifest.py

cborutil: change buffering strategy

Profiling revealed that we were spending a lot of time on the
line that was concatenating the old buffer with the incoming data
when attempting to decode long byte strings, such as manifest
revisions.

Essentially, we were feeding N chunks of size len(X) << len(Y) into
decode() and continuously allocating a new, larger buffer to hold
the undecoded input. This created substantial memory churn and
slowed down execution.

Changing the code to aggregate pending chunks in a list until we
have enough data to fully decode the next atom makes things much
more efficient.

I don't have exact data, but I recall the old code spending >1s
on manifest fulltexts from the mozilla-unified repo. The new code
doesn't significantly appear in profile output.

Differential Revision: https://phab.mercurial-scm.org/D4854

from __future__ import absolute_import

import binascii
import itertools
import silenttestrunner
import unittest

from mercurial import (
    manifest as manifestmod,
    match as matchmod,
)

EMTPY_MANIFEST = b''

HASH_1 = b'1' * 40
BIN_HASH_1 = binascii.unhexlify(HASH_1)
HASH_2 = b'f' * 40
BIN_HASH_2 = binascii.unhexlify(HASH_2)
HASH_3 = b'1234567890abcdef0987654321deadbeef0fcafe'
BIN_HASH_3 = binascii.unhexlify(HASH_3)
A_SHORT_MANIFEST = (
    b'bar/baz/qux.py\0%(hash2)s%(flag2)s\n'
    b'foo\0%(hash1)s%(flag1)s\n'
    ) % {b'hash1': HASH_1,
         b'flag1': b'',
         b'hash2': HASH_2,
         b'flag2': b'l',
         }

A_DEEPER_MANIFEST = (
    b'a/b/c/bar.py\0%(hash3)s%(flag1)s\n'
    b'a/b/c/bar.txt\0%(hash1)s%(flag1)s\n'
    b'a/b/c/foo.py\0%(hash3)s%(flag1)s\n'
    b'a/b/c/foo.txt\0%(hash2)s%(flag2)s\n'
    b'a/b/d/baz.py\0%(hash3)s%(flag1)s\n'
    b'a/b/d/qux.py\0%(hash1)s%(flag2)s\n'
    b'a/b/d/ten.txt\0%(hash3)s%(flag2)s\n'
    b'a/b/dog.py\0%(hash3)s%(flag1)s\n'
    b'a/b/fish.py\0%(hash2)s%(flag1)s\n'
    b'a/c/london.py\0%(hash3)s%(flag2)s\n'
    b'a/c/paper.txt\0%(hash2)s%(flag2)s\n'
    b'a/c/paris.py\0%(hash2)s%(flag1)s\n'
    b'a/d/apple.py\0%(hash3)s%(flag1)s\n'
    b'a/d/pizza.py\0%(hash3)s%(flag2)s\n'
    b'a/green.py\0%(hash1)s%(flag2)s\n'
    b'a/purple.py\0%(hash2)s%(flag1)s\n'
    b'app.py\0%(hash3)s%(flag1)s\n'
    b'readme.txt\0%(hash2)s%(flag1)s\n'
    ) % {b'hash1': HASH_1,
         b'flag1': b'',
         b'hash2': HASH_2,
         b'flag2': b'l',
         b'hash3': HASH_3,
         }

HUGE_MANIFEST_ENTRIES = 200001

izip = getattr(itertools, 'izip', zip)
if 'xrange' not in globals():
    xrange = range

A_HUGE_MANIFEST = b''.join(sorted(
    b'file%d\0%s%s\n' % (i, h, f) for i, h, f in
    izip(xrange(200001),
         itertools.cycle((HASH_1, HASH_2)),
         itertools.cycle((b'', b'x', b'l')))))

class basemanifesttests(object):
    def parsemanifest(self, text):
        raise NotImplementedError('parsemanifest not implemented by test case')

    def testEmptyManifest(self):
        m = self.parsemanifest(EMTPY_MANIFEST)
        self.assertEqual(0, len(m))
        self.assertEqual([], list(m))

    def testManifest(self):
        m = self.parsemanifest(A_SHORT_MANIFEST)
        self.assertEqual([b'bar/baz/qux.py', b'foo'], list(m))
        self.assertEqual(BIN_HASH_2, m[b'bar/baz/qux.py'])
        self.assertEqual(b'l', m.flags(b'bar/baz/qux.py'))
        self.assertEqual(BIN_HASH_1, m[b'foo'])
        self.assertEqual(b'', m.flags(b'foo'))
        with self.assertRaises(KeyError):
            m[b'wat']

    def testSetItem(self):
        want = BIN_HASH_1

        m = self.parsemanifest(EMTPY_MANIFEST)
        m[b'a'] = want
        self.assertIn(b'a', m)
        self.assertEqual(want, m[b'a'])
        self.assertEqual(b'a\0' + HASH_1 + b'\n', m.text())

        m = self.parsemanifest(A_SHORT_MANIFEST)
        m[b'a'] = want
        self.assertEqual(want, m[b'a'])
        self.assertEqual(b'a\0' + HASH_1 + b'\n' + A_SHORT_MANIFEST,
                         m.text())

    def testSetFlag(self):
        want = b'x'

        m = self.parsemanifest(EMTPY_MANIFEST)
        # first add a file; a file-less flag makes no sense
        m[b'a'] = BIN_HASH_1
        m.setflag(b'a', want)
        self.assertEqual(want, m.flags(b'a'))
        self.assertEqual(b'a\0' + HASH_1 + want + b'\n', m.text())

        m = self.parsemanifest(A_SHORT_MANIFEST)
        # first add a file; a file-less flag makes no sense
        m[b'a'] = BIN_HASH_1
        m.setflag(b'a', want)
        self.assertEqual(want, m.flags(b'a'))
        self.assertEqual(b'a\0' + HASH_1 + want + b'\n' + A_SHORT_MANIFEST,
                         m.text())

    def testCopy(self):
        m = self.parsemanifest(A_SHORT_MANIFEST)
        m[b'a'] = BIN_HASH_1
        m2 = m.copy()
        del m
        del m2 # make sure we don't double free() anything

    def testCompaction(self):
        unhex = binascii.unhexlify
        h1, h2 = unhex(HASH_1), unhex(HASH_2)
        m = self.parsemanifest(A_SHORT_MANIFEST)
        m[b'alpha'] = h1
        m[b'beta'] = h2
        del m[b'foo']
        want = b'alpha\0%s\nbar/baz/qux.py\0%sl\nbeta\0%s\n' % (
            HASH_1, HASH_2, HASH_2)
        self.assertEqual(want, m.text())
        self.assertEqual(3, len(m))
        self.assertEqual([b'alpha', b'bar/baz/qux.py', b'beta'], list(m))
        self.assertEqual(h1, m[b'alpha'])
        self.assertEqual(h2, m[b'bar/baz/qux.py'])
        self.assertEqual(h2, m[b'beta'])
        self.assertEqual(b'', m.flags(b'alpha'))
        self.assertEqual(b'l', m.flags(b'bar/baz/qux.py'))
        self.assertEqual(b'', m.flags(b'beta'))
        with self.assertRaises(KeyError):
            m[b'foo']

    def testSetGetNodeSuffix(self):
        clean = self.parsemanifest(A_SHORT_MANIFEST)
        m = self.parsemanifest(A_SHORT_MANIFEST)
        h = m[b'foo']
        f = m.flags(b'foo')
        want = h + b'a'
        # Merge code wants to set 21-byte fake hashes at times
        m[b'foo'] = want
        self.assertEqual(want, m[b'foo'])
        self.assertEqual([(b'bar/baz/qux.py', BIN_HASH_2),
                          (b'foo', BIN_HASH_1 + b'a')],
                         list(m.items()))
        # Sometimes it even tries a 22-byte fake hash, but we can
        # return 21 and it'll work out
        m[b'foo'] = want + b'+'
        self.assertEqual(want, m[b'foo'])
        # make sure the suffix survives a copy
        match = matchmod.match(b'', b'', [b're:foo'])
        m2 = m.matches(match)
        self.assertEqual(want, m2[b'foo'])
        self.assertEqual(1, len(m2))
        m2 = m.copy()
        self.assertEqual(want, m2[b'foo'])
        # suffix with iteration
        self.assertEqual([(b'bar/baz/qux.py', BIN_HASH_2),
                          (b'foo', want)],
                         list(m.items()))

        # shows up in diff
        self.assertEqual({b'foo': ((want, f), (h, b''))}, m.diff(clean))
        self.assertEqual({b'foo': ((h, b''), (want, f))}, clean.diff(m))

    def testMatchException(self):
        m = self.parsemanifest(A_SHORT_MANIFEST)
        match = matchmod.match(b'', b'', [b're:.*'])
        def filt(path):
            if path == b'foo':
                assert False
            return True
        match.matchfn = filt
        with self.assertRaises(AssertionError):
            m.matches(match)

    def testRemoveItem(self):
        m = self.parsemanifest(A_SHORT_MANIFEST)
        del m[b'foo']
        with self.assertRaises(KeyError):
            m[b'foo']
        self.assertEqual(1, len(m))
        self.assertEqual(1, len(list(m)))
        # now restore and make sure everything works right
        m[b'foo'] = b'a' * 20
        self.assertEqual(2, len(m))
        self.assertEqual(2, len(list(m)))

    def testManifestDiff(self):
        MISSING = (None, b'')
        addl = b'z-only-in-left\0' + HASH_1 + b'\n'
        addr = b'z-only-in-right\0' + HASH_2 + b'x\n'
        left = self.parsemanifest(
            A_SHORT_MANIFEST.replace(HASH_1, HASH_3 + b'x') + addl)
        right = self.parsemanifest(A_SHORT_MANIFEST + addr)
        want = {
            b'foo': ((BIN_HASH_3, b'x'),
                     (BIN_HASH_1, b'')),
            b'z-only-in-left': ((BIN_HASH_1, b''), MISSING),
            b'z-only-in-right': (MISSING, (BIN_HASH_2, b'x')),
            }
        self.assertEqual(want, left.diff(right))

        want = {
            b'bar/baz/qux.py': (MISSING, (BIN_HASH_2, b'l')),
            b'foo': (MISSING, (BIN_HASH_3, b'x')),
            b'z-only-in-left': (MISSING, (BIN_HASH_1, b'')),
            }
        self.assertEqual(want, self.parsemanifest(EMTPY_MANIFEST).diff(left))

        want = {
            b'bar/baz/qux.py': ((BIN_HASH_2, b'l'), MISSING),
            b'foo': ((BIN_HASH_3, b'x'), MISSING),
            b'z-only-in-left': ((BIN_HASH_1, b''), MISSING),
            }
        self.assertEqual(want, left.diff(self.parsemanifest(EMTPY_MANIFEST)))
        copy = right.copy()
        del copy[b'z-only-in-right']
        del right[b'foo']
        want = {
            b'foo': (MISSING, (BIN_HASH_1, b'')),
            b'z-only-in-right': ((BIN_HASH_2, b'x'), MISSING),
            }
        self.assertEqual(want, right.diff(copy))

        short = self.parsemanifest(A_SHORT_MANIFEST)
        pruned = short.copy()
        del pruned[b'foo']
        want = {
            b'foo': ((BIN_HASH_1, b''), MISSING),
            }
        self.assertEqual(want, short.diff(pruned))
        want = {
            b'foo': (MISSING, (BIN_HASH_1, b'')),
            }
        self.assertEqual(want, pruned.diff(short))
        want = {
            b'bar/baz/qux.py': None,
            b'foo': (MISSING, (BIN_HASH_1, b'')),
            }
        self.assertEqual(want, pruned.diff(short, clean=True))

    def testReversedLines(self):
        backwards = b''.join(
            l + b'\n' for l in reversed(A_SHORT_MANIFEST.split(b'\n')) if l)
        try:
            self.parsemanifest(backwards)
            self.fail('Should have raised ValueError')
        except ValueError as v:
            self.assertIn('Manifest lines not in sorted order.', str(v))

    def testNoTerminalNewline(self):
        try:
            self.parsemanifest(A_SHORT_MANIFEST + b'wat')
            self.fail('Should have raised ValueError')
        except ValueError as v:
            self.assertIn('Manifest did not end in a newline.', str(v))

    def testNoNewLineAtAll(self):
        try:
            self.parsemanifest(b'wat')
            self.fail('Should have raised ValueError')
        except ValueError as v:
            self.assertIn('Manifest did not end in a newline.', str(v))

    def testHugeManifest(self):
        m = self.parsemanifest(A_HUGE_MANIFEST)
        self.assertEqual(HUGE_MANIFEST_ENTRIES, len(m))
        self.assertEqual(len(m), len(list(m)))

    def testMatchesMetadata(self):
        '''Tests matches() for a few specific files to make sure that both
        the set of files as well as their flags and nodeids are correct in
        the resulting manifest.'''
        m = self.parsemanifest(A_HUGE_MANIFEST)

        match = matchmod.match(b'/', b'',
                [b'file1', b'file200', b'file300'], exact=True)
        m2 = m.matches(match)

        w = (b'file1\0%sx\n'
             b'file200\0%sl\n'
             b'file300\0%s\n') % (HASH_2, HASH_1, HASH_1)
        self.assertEqual(w, m2.text())

    def testMatchesNonexistentFile(self):
        '''Tests matches() for a small set of specific files, including one
        nonexistent file to make sure in only matches against existing files.
        '''
        m = self.parsemanifest(A_DEEPER_MANIFEST)

        match = matchmod.match(b'/', b'',
                [b'a/b/c/bar.txt', b'a/b/d/qux.py',
                 b'readme.txt', b'nonexistent'],
                exact=True)
        m2 = m.matches(match)

        self.assertEqual(
                [b'a/b/c/bar.txt', b'a/b/d/qux.py', b'readme.txt'],
                m2.keys())

    def testMatchesNonexistentDirectory(self):
        '''Tests matches() for a relpath match on a directory that doesn't
        actually exist.'''
        m = self.parsemanifest(A_DEEPER_MANIFEST)

        match = matchmod.match(b'/', b'', [b'a/f'], default=b'relpath')
        m2 = m.matches(match)

        self.assertEqual([], m2.keys())

    def testMatchesExactLarge(self):
        '''Tests matches() for files matching a large list of exact files.
        '''
        m = self.parsemanifest(A_HUGE_MANIFEST)

        flist = m.keys()[80:300]
        match = matchmod.match(b'/', b'', flist, exact=True)
        m2 = m.matches(match)

        self.assertEqual(flist, m2.keys())

    def testMatchesFull(self):
        '''Tests matches() for what should be a full match.'''
        m = self.parsemanifest(A_DEEPER_MANIFEST)

        match = matchmod.match(b'/', b'', [b''])
        m2 = m.matches(match)

        self.assertEqual(m.keys(), m2.keys())

    def testMatchesDirectory(self):
        '''Tests matches() on a relpath match on a directory, which should
        match against all files within said directory.'''
        m = self.parsemanifest(A_DEEPER_MANIFEST)

        match = matchmod.match(b'/', b'', [b'a/b'], default=b'relpath')
        m2 = m.matches(match)

        self.assertEqual([
            b'a/b/c/bar.py', b'a/b/c/bar.txt', b'a/b/c/foo.py',
            b'a/b/c/foo.txt',
            b'a/b/d/baz.py', b'a/b/d/qux.py', b'a/b/d/ten.txt', b'a/b/dog.py',
            b'a/b/fish.py'], m2.keys())

    def testMatchesExactPath(self):
        '''Tests matches() on an exact match on a directory, which should
        result in an empty manifest because you can't perform an exact match
        against a directory.'''
        m = self.parsemanifest(A_DEEPER_MANIFEST)

        match = matchmod.match(b'/', b'', [b'a/b'], exact=True)
        m2 = m.matches(match)

        self.assertEqual([], m2.keys())

    def testMatchesCwd(self):
        '''Tests matches() on a relpath match with the current directory ('.')
        when not in the root directory.'''
        m = self.parsemanifest(A_DEEPER_MANIFEST)

        match = matchmod.match(b'/', b'a/b', [b'.'], default=b'relpath')
        m2 = m.matches(match)

        self.assertEqual([
            b'a/b/c/bar.py', b'a/b/c/bar.txt', b'a/b/c/foo.py',
            b'a/b/c/foo.txt', b'a/b/d/baz.py', b'a/b/d/qux.py',
            b'a/b/d/ten.txt', b'a/b/dog.py', b'a/b/fish.py'], m2.keys())

    def testMatchesWithPattern(self):
        '''Tests matches() for files matching a pattern that reside
        deeper than the specified directory.'''
        m = self.parsemanifest(A_DEEPER_MANIFEST)

        match = matchmod.match(b'/', b'', [b'a/b/*/*.txt'])
        m2 = m.matches(match)

        self.assertEqual(
                [b'a/b/c/bar.txt', b'a/b/c/foo.txt', b'a/b/d/ten.txt'],
                m2.keys())

class testmanifestdict(unittest.TestCase, basemanifesttests):
    def parsemanifest(self, text):
        return manifestmod.manifestdict(text)

class testtreemanifest(unittest.TestCase, basemanifesttests):
    def parsemanifest(self, text):
        return manifestmod.treemanifest(b'', text)

    def testWalkSubtrees(self):
        m = self.parsemanifest(A_DEEPER_MANIFEST)

        dirs = [s._dir for s in m.walksubtrees()]
        self.assertEqual(
            sorted([
                b'', b'a/', b'a/c/', b'a/d/', b'a/b/', b'a/b/c/', b'a/b/d/']),
            sorted(dirs)
        )

        match = matchmod.match(b'/', b'', [b'path:a/b/'])
        dirs = [s._dir for s in m.walksubtrees(matcher=match)]
        self.assertEqual(
            sorted([b'a/b/', b'a/b/c/', b'a/b/d/']),
            sorted(dirs)
        )

if __name__ == '__main__':
    silenttestrunner.main(__name__)