view tests/test-linelog.py @ 44758:45f3f35cefe7

copies: fix the changeset based algorithm regarding merge

In 99ebde4fec99, we changed the list of files stored into the `files` field.
This lead to the changeset centric copy algorithm to break in various merge
situation involving merge. Older information could reach the merge through
`p1`, and while information from `p2` was strictly fresher, it would get
overwritten anyway.

We update the situation with more details about which revision introduces rename
information. This help use making the right decision in case of merge.

We are now running a more comprehensive suite of test with include this kind of
situation. The behavior differ slightly from the filelog based in a couple of
instance. There is mostly two distinct cases:

1) there are conflicting rename information in a merge (different rename history
on each side). In this case the filelog based implementation arbitrarily pick a
side based on the file-revision-number. So it depends on a local factor. The
changeset centric algorithm will use a deterministic approach, by picking the
information coming from the first parent of the merge. This is stable across
different clone.

2) rename information related to file that exist in both source and destination.
The filelog based implementation do not even try to detect these, however the
changeset centric one get them for "free" (it is simpler to detect them than
not).

The new implementation focus on correctness. Performance improvement will come
later.

Differential Revision: https://phab.mercurial-scm.org/D8244

from __future__ import absolute_import, print_function

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__)