revset: stop serializing node when using "%ln"
Turning hundred of thousand of node from node to hex and back can be slow… what
about we stop doing it?
In many case were we are using node id we should be using revision id. However
this is not a good reason to have a stupidly slow implementation of "%ln".
This caught my attention again because the phase discovery during push make an
extensive use of "%ln" or huge set. In absolute, that phase discovery probably
should use "%ld" and need to improves its algorithmic complexity, but improving
"%ln" seems simple and long overdue. This greatly speeds up `hg push` on
repository with many drafts.
Here are some relevant poulpe benchmarks:
### data-env-vars.name = mozilla-try-2023-03-22-zstd-sparse-revlog
# benchmark.name = hg.command.push
# bin-env-vars.hg.flavor = default
# bin-env-vars.hg.py-re2-module = default
# benchmark.variants.explicit-rev = all-out-heads
# benchmark.variants.issue6528 = disabled
# benchmark.variants.protocol = ssh
# benchmark.variants.reuse-external-delta-parent = default
## benchmark.variants.revs = any-1-extra-rev
before: 44.235070
after: 20.416329 (-53.85%, -23.82)
## benchmark.variants.revs = any-100-extra-rev
before: 49.234697
after: 26.519829 (-46.14%, -22.71)
### benchmark.name = hg.command.bundle
# bin-env-vars.hg.flavor = default
# bin-env-vars.hg.py-re2-module = default
# benchmark.variants.revs = all
# benchmark.variants.type = none-streamv2
## data-env-vars.name = heptapod-public-2024-03-25-zstd-sparse-revlog
before: 10.138396
after: 7.750458 (-23.55%, -2.39)
## data-env-vars.name = mercurial-public-2024-03-22-zstd-sparse-revlog
before: 1.263859
after: 0.700229 (-44.60%, -0.56)
## data-env-vars.name = mozilla-try-2023-03-22-zstd-sparse-revlog
before: 399.484481
after: 346.5089 (-13.26%, -52.98)
## data-env-vars.name = pypy-2024-03-22-zstd-sparse-revlog
before: 4.540080
after: 3.401700 (-25.07%, -1.14)
## data-env-vars.name = tryton-public-2024-03-22-zstd-sparse-revlog
before: 2.975765
after: 1.870798 (-37.13%, -1.10)
import collections
import struct
import unittest
from mercurial import mdiff
class diffreplace(collections.namedtuple('diffreplace', 'start end from_ to')):
def __repr__(self):
return 'diffreplace(%r, %r, %r, %r)' % self
class BdiffTests(unittest.TestCase):
def assert_bdiff_applies(self, a, b):
d = mdiff.textdiff(a, b)
c = a
if d:
c = mdiff.patches(a, [d])
self.assertEqual(
c,
b,
(
"bad diff+patch result from\n %r to\n "
"%r: \nbdiff: %r\npatched: %r" % (a, b, d, c[:200])
),
)
def assert_bdiff(self, a, b):
self.assert_bdiff_applies(a, b)
self.assert_bdiff_applies(b, a)
def test_bdiff_basic(self):
cases = [
(b"a\nc\n\n\n\n", b"a\nb\n\n\n"),
(b"a\nb\nc\n", b"a\nc\n"),
(b"", b""),
(b"a\nb\nc", b"a\nb\nc"),
(b"a\nb\nc\nd\n", b"a\nd\n"),
(b"a\nb\nc\nd\n", b"a\nc\ne\n"),
(b"a\nb\nc\n", b"a\nc\n"),
(b"a\n", b"c\na\nb\n"),
(b"a\n", b""),
(b"a\n", b"b\nc\n"),
(b"a\n", b"c\na\n"),
(b"", b"adjfkjdjksdhfksj"),
(b"", b"ab"),
(b"", b"abc"),
(b"a", b"a"),
(b"ab", b"ab"),
(b"abc", b"abc"),
(b"a\n", b"a\n"),
(b"a\nb", b"a\nb"),
]
for a, b in cases:
self.assert_bdiff(a, b)
def showdiff(self, a, b):
bin = mdiff.textdiff(a, b)
pos = 0
q = 0
actions = []
while pos < len(bin):
p1, p2, l = struct.unpack(">lll", bin[pos : pos + 12])
pos += 12
if p1:
actions.append(a[q:p1])
actions.append(diffreplace(p1, p2, a[p1:p2], bin[pos : pos + l]))
pos += l
q = p2
if q < len(a):
actions.append(a[q:])
return actions
def test_issue1295(self):
cases = [
(
b"x\n\nx\n\nx\n\nx\n\nz\n",
b"x\n\nx\n\ny\n\nx\n\nx\n\nz\n",
[
b'x\n\nx\n\n',
diffreplace(6, 6, b'', b'y\n\n'),
b'x\n\nx\n\nz\n',
],
),
(
b"x\n\nx\n\nx\n\nx\n\nz\n",
b"x\n\nx\n\ny\n\nx\n\ny\n\nx\n\nz\n",
[
b'x\n\nx\n\n',
diffreplace(6, 6, b'', b'y\n\n'),
b'x\n\n',
diffreplace(9, 9, b'', b'y\n\n'),
b'x\n\nz\n',
],
),
]
for old, new, want in cases:
self.assertEqual(self.showdiff(old, new), want)
def test_issue1295_varies_on_pure(self):
# we should pick up abbbc. rather than bc.de as the longest match
got = self.showdiff(
b"a\nb\nb\nb\nc\n.\nd\ne\n.\nf\n",
b"a\nb\nb\na\nb\nb\nb\nc\n.\nb\nc\n.\nd\ne\nf\n",
)
want_c = [
b'a\nb\nb\n',
diffreplace(6, 6, b'', b'a\nb\nb\nb\nc\n.\n'),
b'b\nc\n.\nd\ne\n',
diffreplace(16, 18, b'.\n', b''),
b'f\n',
]
want_pure = [
diffreplace(0, 0, b'', b'a\nb\nb\n'),
b'a\nb\nb\nb\nc\n.\n',
diffreplace(12, 12, b'', b'b\nc\n.\n'),
b'd\ne\n',
diffreplace(16, 18, b'.\n', b''),
b'f\n',
]
self.assertTrue(
got in (want_c, want_pure),
'got: %r, wanted either %r or %r' % (got, want_c, want_pure),
)
def test_fixws(self):
cases = [
(b" \ta\r b\t\n", b"ab\n", 1),
(b" \ta\r b\t\n", b" a b\n", 0),
(b"", b"", 1),
(b"", b"", 0),
]
for a, b, allws in cases:
c = mdiff.fixws(a, allws)
self.assertEqual(
c, b, 'fixws(%r) want %r got %r (allws=%r)' % (a, b, c, allws)
)
def test_nice_diff_for_trivial_change(self):
self.assertEqual(
self.showdiff(
b''.join(b'<%d\n-\n' % i for i in range(5)),
b''.join(b'>%d\n-\n' % i for i in range(5)),
),
[
diffreplace(0, 3, b'<0\n', b'>0\n'),
b'-\n',
diffreplace(5, 8, b'<1\n', b'>1\n'),
b'-\n',
diffreplace(10, 13, b'<2\n', b'>2\n'),
b'-\n',
diffreplace(15, 18, b'<3\n', b'>3\n'),
b'-\n',
diffreplace(20, 23, b'<4\n', b'>4\n'),
b'-\n',
],
)
def test_prefer_appending(self):
# 1 line to 3 lines
self.assertEqual(
self.showdiff(b'a\n', b'a\n' * 3),
[b'a\n', diffreplace(2, 2, b'', b'a\na\n')],
)
# 1 line to 5 lines
self.assertEqual(
self.showdiff(b'a\n', b'a\n' * 5),
[b'a\n', diffreplace(2, 2, b'', b'a\na\na\na\n')],
)
def test_prefer_removing_trailing(self):
# 3 lines to 1 line
self.assertEqual(
self.showdiff(b'a\n' * 3, b'a\n'),
[b'a\n', diffreplace(2, 6, b'a\na\n', b'')],
)
# 5 lines to 1 line
self.assertEqual(
self.showdiff(b'a\n' * 5, b'a\n'),
[b'a\n', diffreplace(2, 10, b'a\na\na\na\n', b'')],
)
if __name__ == '__main__':
import silenttestrunner
silenttestrunner.main(__name__)