view tests/test-simplemerge.py @ 40042:208303a8172c

obsolete: explicitly track folds inside the markers

We now record information to be able to recognize "fold" event from
obsolescence markers. To do so, we track the following pieces of information:

a) a fold ID. Unique to that fold (per successor),
b) the number of predecessors,
c) the index of the predecessor in that fold.

We will now be able to create an algorithm able to find "predecessorssets".

We now store this data in the generic "metadata" field of the markers.
Updating the format to have a more compact storage for this would be useful.

This way of tracking a fold through multiple markers could be applied to split
too. This would have two advantages:

1) We get a simpler format, since number of successors is limited to [0-1].
2) We can better deal with situations where only some of the split successors
   are pushed to a remote repository.

We should look into the relevance of such a change before updating the on-disk
format.

note: unlike splits, folds do not have to deal with cases where only some of
the markers have been synchronized. As they all share the same successor
changesets, they are all relevant to the same nodes.

# 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