branchcache: add a "pure topological head" fast path
In a narrow but actually quick common case, all topological heads are all on
the same branch and all open. In this case, computing the branch map is very
simple. We can quickly detect situation where this situation will not change.
So we update the V3 format to be able to express this situation and upgrade the
update code to detect we remains in that mode.
The branch cache is populated with the actual value when the branch map is
accessed, but the update_disk method can do the update without needing to
populate it.
import difflib
import random
import unittest
from mercurial import linelog
vecratio = 3 # number of replacelines / number of replacelines_vec
maxlinenum = 0xFFFFFF
maxb1 = 0xFFFFFF
maxdeltaa = 10
maxdeltab = 10
def _genedits(seed, endrev):
lines = []
random.seed(seed)
for rev in range(0, endrev):
n = len(lines)
a1 = random.randint(0, n)
a2 = random.randint(a1, min(n, a1 + maxdeltaa))
b1 = random.randint(0, maxb1)
b2 = random.randint(b1, b1 + maxdeltab)
usevec = not bool(random.randint(0, vecratio))
if usevec:
blines = [
(random.randint(0, rev), random.randint(0, maxlinenum))
for _ in range(b1, b2)
]
else:
blines = [(rev, bidx) for bidx in range(b1, b2)]
lines[a1:a2] = blines
yield lines, rev, a1, a2, b1, b2, blines, usevec
class linelogtests(unittest.TestCase):
def testlinelogencodedecode(self):
program = [
linelog._eof(0, 0),
linelog._jge(41, 42),
linelog._jump(0, 43),
linelog._eof(0, 0),
linelog._jl(44, 45),
linelog._line(46, 47),
]
ll = linelog.linelog(program, maxrev=100)
enc = ll.encode()
# round-trips okay
self.assertEqual(linelog.linelog.fromdata(enc)._program, ll._program)
self.assertEqual(linelog.linelog.fromdata(enc), ll)
# This encoding matches the encoding used by hg-experimental's
# linelog file, or is supposed to if it doesn't.
self.assertEqual(
enc,
(
b'\x00\x00\x01\x90\x00\x00\x00\x06'
b'\x00\x00\x00\xa4\x00\x00\x00*'
b'\x00\x00\x00\x00\x00\x00\x00+'
b'\x00\x00\x00\x00\x00\x00\x00\x00'
b'\x00\x00\x00\xb1\x00\x00\x00-'
b'\x00\x00\x00\xba\x00\x00\x00/'
),
)
def testsimpleedits(self):
ll = linelog.linelog()
# Initial revision: add lines 0, 1, and 2
ll.replacelines(1, 0, 0, 0, 3)
self.assertEqual(
[(l.rev, l.linenum) for l in ll.annotate(1)],
[
(1, 0),
(1, 1),
(1, 2),
],
)
# Replace line 1 with a new line
ll.replacelines(2, 1, 2, 1, 2)
self.assertEqual(
[(l.rev, l.linenum) for l in ll.annotate(2)],
[
(1, 0),
(2, 1),
(1, 2),
],
)
# delete a line out of 2
ll.replacelines(3, 1, 2, 0, 0)
self.assertEqual(
[(l.rev, l.linenum) for l in ll.annotate(3)],
[
(1, 0),
(1, 2),
],
)
# annotation of 1 is unchanged
self.assertEqual(
[(l.rev, l.linenum) for l in ll.annotate(1)],
[
(1, 0),
(1, 1),
(1, 2),
],
)
ll.annotate(3) # set internal state to revision 3
start = ll.getoffset(0)
end = ll.getoffset(1)
self.assertEqual(
ll.getalllines(start, end),
[
(1, 0),
(2, 1),
(1, 1),
],
)
self.assertEqual(
ll.getalllines(),
[
(1, 0),
(2, 1),
(1, 1),
(1, 2),
],
)
def testparseclinelogfile(self):
# This data is what the replacements in testsimpleedits
# produce when fed to the original linelog.c implementation.
data = (
b'\x00\x00\x00\x0c\x00\x00\x00\x0f'
b'\x00\x00\x00\x00\x00\x00\x00\x02'
b'\x00\x00\x00\x05\x00\x00\x00\x06'
b'\x00\x00\x00\x06\x00\x00\x00\x00'
b'\x00\x00\x00\x00\x00\x00\x00\x07'
b'\x00\x00\x00\x06\x00\x00\x00\x02'
b'\x00\x00\x00\x00\x00\x00\x00\x00'
b'\x00\x00\x00\t\x00\x00\x00\t'
b'\x00\x00\x00\x00\x00\x00\x00\x0c'
b'\x00\x00\x00\x08\x00\x00\x00\x05'
b'\x00\x00\x00\x06\x00\x00\x00\x01'
b'\x00\x00\x00\x00\x00\x00\x00\x05'
b'\x00\x00\x00\x0c\x00\x00\x00\x05'
b'\x00\x00\x00\n\x00\x00\x00\x01'
b'\x00\x00\x00\x00\x00\x00\x00\t'
)
llc = linelog.linelog.fromdata(data)
self.assertEqual(
[(l.rev, l.linenum) for l in llc.annotate(1)],
[
(1, 0),
(1, 1),
(1, 2),
],
)
self.assertEqual(
[(l.rev, l.linenum) for l in llc.annotate(2)],
[
(1, 0),
(2, 1),
(1, 2),
],
)
self.assertEqual(
[(l.rev, l.linenum) for l in llc.annotate(3)],
[
(1, 0),
(1, 2),
],
)
# Check we emit the same bytecode.
ll = linelog.linelog()
# Initial revision: add lines 0, 1, and 2
ll.replacelines(1, 0, 0, 0, 3)
# Replace line 1 with a new line
ll.replacelines(2, 1, 2, 1, 2)
# delete a line out of 2
ll.replacelines(3, 1, 2, 0, 0)
diff = '\n ' + '\n '.join(
difflib.unified_diff(
ll.debugstr().splitlines(),
llc.debugstr().splitlines(),
'python',
'c',
lineterm='',
)
)
self.assertEqual(ll._program, llc._program, 'Program mismatch: ' + diff)
# Done as a secondary step so we get a better result if the
# program is where the mismatch is.
self.assertEqual(ll, llc)
self.assertEqual(ll.encode(), data)
def testanothersimplecase(self):
ll = linelog.linelog()
ll.replacelines(3, 0, 0, 0, 2)
ll.replacelines(4, 0, 2, 0, 0)
self.assertEqual([(l.rev, l.linenum) for l in ll.annotate(4)], [])
self.assertEqual(
[(l.rev, l.linenum) for l in ll.annotate(3)], [(3, 0), (3, 1)]
)
# rev 2 is empty because contents were only ever introduced in rev 3
self.assertEqual([(l.rev, l.linenum) for l in ll.annotate(2)], [])
def testrandomedits(self):
# Inspired by original linelog tests.
seed = random.random()
numrevs = 2000
ll = linelog.linelog()
# Populate linelog
for lines, rev, a1, a2, b1, b2, blines, usevec in _genedits(
seed, numrevs
):
if usevec:
ll.replacelines_vec(rev, a1, a2, blines)
else:
ll.replacelines(rev, a1, a2, b1, b2)
ll.annotate(rev)
self.assertEqual(ll.annotateresult, lines)
# Verify we can get back these states by annotating each rev
for lines, rev, a1, a2, b1, b2, blines, usevec in _genedits(
seed, numrevs
):
ar = ll.annotate(rev)
self.assertEqual([(l.rev, l.linenum) for l in ar], lines)
def testinfinitebadprogram(self):
ll = linelog.linelog.fromdata(
b'\x00\x00\x00\x00\x00\x00\x00\x02' # header
b'\x00\x00\x00\x00\x00\x00\x00\x01' # JUMP to self
)
with self.assertRaises(linelog.LineLogError):
# should not be an infinite loop and raise
ll.annotate(1)
if __name__ == '__main__':
import silenttestrunner
silenttestrunner.main(__name__)