view tests/test-simplemerge.py @ 39356:c8e4eae84808

narrow: add server logic to send cg while widening without ellipsis

Before this patch, if you try to widen a narrow clone without ellipsis enabled,
it will be broken and the exchange.pull() done by tracked command to widen the
clone will be no-op because no custom logic exists for this and server sees that
we have all csets and it says `no changes found`.

The widening with ellipsis send KILL for existing changegroups and send new
changegroups because of the change in ellipsis hash, but we can prevent that in
non-ellipsis cases.

This patch adds server side logic to send the changegroups for the changesets
which are on the client again with filelogs and manifests for the new includes.
This is a very starting implementation and we send changegroups and manifests
too while we can prevent them.

Following things can definitely be improved in the logic this patch adds:

  1) Send just the filelogs and treemanifests
  2) Send the filelogs only for the additions in the include

I tried 1) here but the code is coupled tightly and the way I was able to do
that was hacking into the changegroup generation code in a very dirty way, like
adding conditionals and preventing the yield.

This patch also adds a 'widen' kwarg to prevent other commands except widening
to go through that codepath.

The test changes demonstrate that the new implementation is correct and fixes
things.

Differential Revision: https://phab.mercurial-scm.org/D4383

# Copyright (C) 2004, 2005 Canonical Ltd
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, see <http://www.gnu.org/licenses/>.

from __future__ import absolute_import

import unittest
from mercurial import (
    error,
    simplemerge,
    util,
)

from mercurial.utils import (
    stringutil,
)

TestCase = unittest.TestCase
# bzr compatible interface, for the tests
class Merge3(simplemerge.Merge3Text):
    """3-way merge of texts.

    Given BASE, OTHER, THIS, tries to produce a combined text
    incorporating the changes from both BASE->OTHER and BASE->THIS.
    All three will typically be sequences of lines."""
    def __init__(self, base, a, b):
        basetext = b'\n'.join([i.strip(b'\n') for i in base] + [b''])
        atext = b'\n'.join([i.strip(b'\n') for i in a] + [b''])
        btext = b'\n'.join([i.strip(b'\n') for i in b] + [b''])
        if (stringutil.binary(basetext) or stringutil.binary(atext)
            or stringutil.binary(btext)):
            raise error.Abort(b"don't know how to merge binary files")
        simplemerge.Merge3Text.__init__(self, basetext, atext, btext,
                                        base, a, b)

CantReprocessAndShowBase = simplemerge.CantReprocessAndShowBase

def split_lines(t):
    return util.stringio(t).readlines()

############################################################
# test case data from the gnu diffutils manual
# common base
TZU = split_lines(b"""     The Nameless is the origin of Heaven and Earth;
     The named is the mother of all things.

     Therefore let there always be non-being,
       so we may see their subtlety,
     And let there always be being,
       so we may see their outcome.
     The two are the same,
     But after they are produced,
       they have different names.
     They both may be called deep and profound.
     Deeper and more profound,
     The door of all subtleties!
""")

LAO = split_lines(b"""     The Way that can be told of is not the eternal Way;
     The name that can be named is not the eternal name.
     The Nameless is the origin of Heaven and Earth;
     The Named is the mother of all things.
     Therefore let there always be non-being,
       so we may see their subtlety,
     And let there always be being,
       so we may see their outcome.
     The two are the same,
     But after they are produced,
       they have different names.
""")


TAO = split_lines(b"""     The Way that can be told of is not the eternal Way;
     The name that can be named is not the eternal name.
     The Nameless is the origin of Heaven and Earth;
     The named is the mother of all things.

     Therefore let there always be non-being,
       so we may see their subtlety,
     And let there always be being,
       so we may see their result.
     The two are the same,
     But after they are produced,
       they have different names.

       -- The Way of Lao-Tzu, tr. Wing-tsit Chan

""")

MERGED_RESULT = split_lines(b"""\
     The Way that can be told of is not the eternal Way;
     The name that can be named is not the eternal name.
     The Nameless is the origin of Heaven and Earth;
     The Named is the mother of all things.
     Therefore let there always be non-being,
       so we may see their subtlety,
     And let there always be being,
       so we may see their result.
     The two are the same,
     But after they are produced,
       they have different names.\
\n<<<<<<< LAO\
\n=======

       -- The Way of Lao-Tzu, tr. Wing-tsit Chan
\
\n>>>>>>> TAO
""")

class TestMerge3(TestCase):
    def log(self, msg):
        pass

    def test_no_changes(self):
        """No conflicts because nothing changed"""
        m3 = Merge3([b'aaa', b'bbb'],
                    [b'aaa', b'bbb'],
                    [b'aaa', b'bbb'])

        self.assertEqual(m3.find_unconflicted(),
                         [(0, 2)])

        self.assertEqual(list(m3.find_sync_regions()),
                         [(0, 2,
                           0, 2,
                           0, 2),
                          (2, 2,  2, 2,  2, 2)])

        self.assertEqual(list(m3.merge_regions()),
                         [(b'unchanged', 0, 2)])

        self.assertEqual(list(m3.merge_groups()),
                         [(b'unchanged', [b'aaa', b'bbb'])])

    def test_front_insert(self):
        m3 = Merge3([b'zz'],
                    [b'aaa', b'bbb', b'zz'],
                    [b'zz'])

        # todo: should use a sentinel at end as from get_matching_blocks
        # to match without zz
        self.assertEqual(list(m3.find_sync_regions()),
                         [(0, 1,  2, 3,  0, 1),
                          (1, 1,  3, 3,  1, 1)])

        self.assertEqual(list(m3.merge_regions()),
                         [(b'a', 0, 2),
                          (b'unchanged', 0, 1)])

        self.assertEqual(list(m3.merge_groups()),
                         [(b'a', [b'aaa', b'bbb']),
                          (b'unchanged', [b'zz'])])

    def test_null_insert(self):
        m3 = Merge3([],
                    [b'aaa', b'bbb'],
                    [])
        # todo: should use a sentinel at end as from get_matching_blocks
        # to match without zz
        self.assertEqual(list(m3.find_sync_regions()),
                         [(0, 0,  2, 2,  0, 0)])

        self.assertEqual(list(m3.merge_regions()),
                         [(b'a', 0, 2)])

        self.assertEqual(list(m3.merge_lines()),
                         [b'aaa', b'bbb'])

    def test_no_conflicts(self):
        """No conflicts because only one side changed"""
        m3 = Merge3([b'aaa', b'bbb'],
                    [b'aaa', b'111', b'bbb'],
                    [b'aaa', b'bbb'])

        self.assertEqual(m3.find_unconflicted(),
                         [(0, 1), (1, 2)])

        self.assertEqual(list(m3.find_sync_regions()),
                         [(0, 1,  0, 1,  0, 1),
                          (1, 2,  2, 3,  1, 2),
                          (2, 2,  3, 3,  2, 2)])

        self.assertEqual(list(m3.merge_regions()),
                         [(b'unchanged', 0, 1),
                          (b'a', 1, 2),
                          (b'unchanged', 1, 2)])

    def test_append_a(self):
        m3 = Merge3([b'aaa\n', b'bbb\n'],
                    [b'aaa\n', b'bbb\n', b'222\n'],
                    [b'aaa\n', b'bbb\n'])

        self.assertEqual(b''.join(m3.merge_lines()),
                         b'aaa\nbbb\n222\n')

    def test_append_b(self):
        m3 = Merge3([b'aaa\n', b'bbb\n'],
                    [b'aaa\n', b'bbb\n'],
                    [b'aaa\n', b'bbb\n', b'222\n'])

        self.assertEqual(b''.join(m3.merge_lines()),
                         b'aaa\nbbb\n222\n')

    def test_append_agreement(self):
        m3 = Merge3([b'aaa\n', b'bbb\n'],
                    [b'aaa\n', b'bbb\n', b'222\n'],
                    [b'aaa\n', b'bbb\n', b'222\n'])

        self.assertEqual(b''.join(m3.merge_lines()),
                         b'aaa\nbbb\n222\n')

    def test_append_clash(self):
        m3 = Merge3([b'aaa\n', b'bbb\n'],
                    [b'aaa\n', b'bbb\n', b'222\n'],
                    [b'aaa\n', b'bbb\n', b'333\n'])

        ml = m3.merge_lines(name_a=b'a',
                            name_b=b'b',
                            start_marker=b'<<',
                            mid_marker=b'--',
                            end_marker=b'>>')
        self.assertEqual(b''.join(ml),
                         b'aaa\n'
                         b'bbb\n'
                         b'<< a\n'
                         b'222\n'
                         b'--\n'
                         b'333\n'
                         b'>> b\n'
                         )

    def test_insert_agreement(self):
        m3 = Merge3([b'aaa\n', b'bbb\n'],
                    [b'aaa\n', b'222\n', b'bbb\n'],
                    [b'aaa\n', b'222\n', b'bbb\n'])

        ml = m3.merge_lines(name_a=b'a',
                            name_b=b'b',
                            start_marker=b'<<',
                            mid_marker=b'--',
                            end_marker=b'>>')
        self.assertEqual(b''.join(ml), b'aaa\n222\nbbb\n')


    def test_insert_clash(self):
        """Both try to insert lines in the same place."""
        m3 = Merge3([b'aaa\n', b'bbb\n'],
                    [b'aaa\n', b'111\n', b'bbb\n'],
                    [b'aaa\n', b'222\n', b'bbb\n'])

        self.assertEqual(m3.find_unconflicted(),
                         [(0, 1), (1, 2)])

        self.assertEqual(list(m3.find_sync_regions()),
                         [(0, 1,  0, 1,  0, 1),
                          (1, 2,  2, 3,  2, 3),
                          (2, 2,  3, 3,  3, 3)])

        self.assertEqual(list(m3.merge_regions()),
                         [(b'unchanged', 0, 1),
                          (b'conflict', 1, 1,  1, 2,  1, 2),
                          (b'unchanged', 1, 2)])

        self.assertEqual(list(m3.merge_groups()),
                         [(b'unchanged', [b'aaa\n']),
                          (b'conflict', [], [b'111\n'], [b'222\n']),
                          (b'unchanged', [b'bbb\n']),
                          ])

        ml = m3.merge_lines(name_a=b'a',
                            name_b=b'b',
                            start_marker=b'<<',
                            mid_marker=b'--',
                            end_marker=b'>>')
        self.assertEqual(b''.join(ml),
b'''aaa
<< a
111
--
222
>> b
bbb
''')

    def test_replace_clash(self):
        """Both try to insert lines in the same place."""
        m3 = Merge3([b'aaa', b'000', b'bbb'],
                    [b'aaa', b'111', b'bbb'],
                    [b'aaa', b'222', b'bbb'])

        self.assertEqual(m3.find_unconflicted(),
                         [(0, 1), (2, 3)])

        self.assertEqual(list(m3.find_sync_regions()),
                         [(0, 1,  0, 1,  0, 1),
                           (2, 3,  2, 3,  2, 3),
                           (3, 3,  3, 3,  3, 3)])

    def test_replace_multi(self):
        """Replacement with regions of different size."""
        m3 = Merge3([b'aaa', b'000', b'000', b'bbb'],
                    [b'aaa', b'111', b'111', b'111', b'bbb'],
                    [b'aaa', b'222', b'222', b'222', b'222', b'bbb'])

        self.assertEqual(m3.find_unconflicted(),
                         [(0, 1), (3, 4)])


        self.assertEqual(list(m3.find_sync_regions()),
                         [(0, 1,  0, 1,  0, 1),
                          (3, 4,  4, 5,  5, 6),
                          (4, 4,  5, 5,  6, 6)])

    def test_merge_poem(self):
        """Test case from diff3 manual"""
        m3 = Merge3(TZU, LAO, TAO)
        ml = list(m3.merge_lines(b'LAO', b'TAO'))
        self.log(b'merge result:')
        self.log(b''.join(ml))
        self.assertEqual(ml, MERGED_RESULT)

    def test_binary(self):
        with self.assertRaises(error.Abort):
            Merge3([b'\x00'], [b'a'], [b'b'])

    def test_dos_text(self):
        base_text = b'a\r\n'
        this_text = b'b\r\n'
        other_text = b'c\r\n'
        m3 = Merge3(base_text.splitlines(True), other_text.splitlines(True),
                    this_text.splitlines(True))
        m_lines = m3.merge_lines(b'OTHER', b'THIS')
        self.assertEqual(b'<<<<<<< OTHER\r\nc\r\n=======\r\nb\r\n'
                         b'>>>>>>> THIS\r\n'.splitlines(True), list(m_lines))

    def test_mac_text(self):
        base_text = b'a\r'
        this_text = b'b\r'
        other_text = b'c\r'
        m3 = Merge3(base_text.splitlines(True), other_text.splitlines(True),
                    this_text.splitlines(True))
        m_lines = m3.merge_lines(b'OTHER', b'THIS')
        self.assertEqual(b'<<<<<<< OTHER\rc\r=======\rb\r'
                         b'>>>>>>> THIS\r'.splitlines(True), list(m_lines))

if __name__ == '__main__':
    # hide the timer
    import time
    orig = time.time
    try:
        time.time = lambda: 0
        unittest.main()
    finally:
        time.time = orig