view tests/test-absorb-filefixupstate.py @ 45584:4c8a93ec6908

merge: store commitinfo if these is a dc or cd conflict

delete-changed or changed-delete conflicts can either be resolved by mergetool,
if some tool is passed and using or by user choose something on prompt or user
doing some `hg revert` after choosing the file to remain conflicted.

If the user decides to keep the changed side, on commit we just reuse the parent
filenode. This is mostly fine unless we are in a distributed environment and
people are doing criss-cross merges.

Since, we don't have recursive merges or any other way of describing the end
result of the merge was an explicit choice and it should be differentiated from
it's ancestors, merge algo during criss-cross merges fails to take in account
the explicit choice made by user and end up with a what-can-be-said-wrong-merge.

The solution which we are trying to fix this is by creating a filenode on commit
instead of reusing the parent filenode. This helps differentiate between
pre-merged filenode and post-merge filenode and kind of tells about the choice
user made.

To implement creating new filenode functionality, we store info about these
files in mergestate so that we can read them on commit and force create a new
filenode.

Differential Revision: https://phab.mercurial-scm.org/D8988

from __future__ import absolute_import, print_function

import itertools
from mercurial import pycompat
from hgext import absorb


class simplefctx(object):
    def __init__(self, content):
        self.content = content

    def data(self):
        return self.content


def insertreturns(x):
    # insert "\n"s after each single char
    if isinstance(x, bytes):
        return b''.join(ch + b'\n' for ch in pycompat.bytestr(x))
    else:
        return pycompat.maplist(insertreturns, x)


def removereturns(x):
    # the revert of "insertreturns"
    if isinstance(x, bytes):
        return x.replace(b'\n', b'')
    else:
        return pycompat.maplist(removereturns, x)


def assertlistequal(lhs, rhs, decorator=lambda x: x):
    if lhs != rhs:
        raise RuntimeError(
            'mismatch:\n actual:   %r\n expected: %r'
            % tuple(map(decorator, [lhs, rhs]))
        )


def testfilefixup(oldcontents, workingcopy, expectedcontents, fixups=None):
    """([str], str, [str], [(rev, a1, a2, b1, b2)]?) -> None

    workingcopy is a string, of which every character denotes a single line.

    oldcontents, expectedcontents are lists of strings, every character of
    every string denots a single line.

    if fixups is not None, it's the expected fixups list and will be checked.
    """
    expectedcontents = insertreturns(expectedcontents)
    oldcontents = insertreturns(oldcontents)
    workingcopy = insertreturns(workingcopy)
    state = absorb.filefixupstate(
        pycompat.maplist(simplefctx, oldcontents), 'path'
    )
    state.diffwith(simplefctx(workingcopy))
    if fixups is not None:
        assertlistequal(state.fixups, fixups)
    state.apply()
    assertlistequal(state.finalcontents, expectedcontents, removereturns)


def buildcontents(linesrevs):
    # linesrevs: [(linecontent : str, revs : [int])]
    revs = set(itertools.chain(*[revs for line, revs in linesrevs]))
    return [b''] + [
        b''.join([l for l, rs in linesrevs if r in rs]) for r in sorted(revs)
    ]


# input case 0: one single commit
case0 = [b'', b'11']

# replace a single chunk
testfilefixup(case0, b'', [b'', b''])
testfilefixup(case0, b'2', [b'', b'2'])
testfilefixup(case0, b'22', [b'', b'22'])
testfilefixup(case0, b'222', [b'', b'222'])

# input case 1: 3 lines, each commit adds one line
case1 = buildcontents([(b'1', [1, 2, 3]), (b'2', [2, 3]), (b'3', [3]),])

# 1:1 line mapping
testfilefixup(case1, b'123', case1)
testfilefixup(case1, b'12c', [b'', b'1', b'12', b'12c'])
testfilefixup(case1, b'1b3', [b'', b'1', b'1b', b'1b3'])
testfilefixup(case1, b'1bc', [b'', b'1', b'1b', b'1bc'])
testfilefixup(case1, b'a23', [b'', b'a', b'a2', b'a23'])
testfilefixup(case1, b'a2c', [b'', b'a', b'a2', b'a2c'])
testfilefixup(case1, b'ab3', [b'', b'a', b'ab', b'ab3'])
testfilefixup(case1, b'abc', [b'', b'a', b'ab', b'abc'])

# non 1:1 edits
testfilefixup(case1, b'abcd', case1)
testfilefixup(case1, b'ab', case1)

# deletion
testfilefixup(case1, b'', [b'', b'', b'', b''])
testfilefixup(case1, b'1', [b'', b'1', b'1', b'1'])
testfilefixup(case1, b'2', [b'', b'', b'2', b'2'])
testfilefixup(case1, b'3', [b'', b'', b'', b'3'])
testfilefixup(case1, b'13', [b'', b'1', b'1', b'13'])

# replaces
testfilefixup(case1, b'1bb3', [b'', b'1', b'1bb', b'1bb3'])

# (confusing) replaces
testfilefixup(case1, b'1bbb', case1)
testfilefixup(case1, b'bbbb', case1)
testfilefixup(case1, b'bbb3', case1)
testfilefixup(case1, b'1b', case1)
testfilefixup(case1, b'bb', case1)
testfilefixup(case1, b'b3', case1)

# insertions at the beginning and the end
testfilefixup(case1, b'123c', [b'', b'1', b'12', b'123c'])
testfilefixup(case1, b'a123', [b'', b'a1', b'a12', b'a123'])

# (confusing) insertions
testfilefixup(case1, b'1a23', case1)
testfilefixup(case1, b'12b3', case1)

# input case 2: delete in the middle
case2 = buildcontents([(b'11', [1, 2]), (b'22', [1]), (b'33', [1, 2]),])

# deletion (optimize code should make it 2 chunks)
testfilefixup(
    case2, b'', [b'', b'22', b''], fixups=[(4, 0, 2, 0, 0), (4, 2, 4, 0, 0)]
)

# 1:1 line mapping
testfilefixup(case2, b'aaaa', [b'', b'aa22aa', b'aaaa'])

# non 1:1 edits
# note: unlike case0, the chunk is not "continuous" and no edit allowed
testfilefixup(case2, b'aaa', case2)

# input case 3: rev 3 reverts rev 2
case3 = buildcontents([(b'1', [1, 2, 3]), (b'2', [2]), (b'3', [1, 2, 3]),])

# 1:1 line mapping
testfilefixup(case3, b'13', case3)
testfilefixup(case3, b'1b', [b'', b'1b', b'12b', b'1b'])
testfilefixup(case3, b'a3', [b'', b'a3', b'a23', b'a3'])
testfilefixup(case3, b'ab', [b'', b'ab', b'a2b', b'ab'])

# non 1:1 edits
testfilefixup(case3, b'a', case3)
testfilefixup(case3, b'abc', case3)

# deletion
testfilefixup(case3, b'', [b'', b'', b'2', b''])

# insertion
testfilefixup(case3, b'a13c', [b'', b'a13c', b'a123c', b'a13c'])

# input case 4: a slightly complex case
case4 = buildcontents(
    [
        (b'1', [1, 2, 3]),
        (b'2', [2, 3]),
        (b'3', [1, 2,]),
        (b'4', [1, 3]),
        (b'5', [3]),
        (b'6', [2, 3]),
        (b'7', [2]),
        (b'8', [2, 3]),
        (b'9', [3]),
    ]
)

testfilefixup(case4, b'1245689', case4)
testfilefixup(case4, b'1a2456bbb', case4)
testfilefixup(case4, b'1abc5689', case4)
testfilefixup(case4, b'1ab5689', [b'', b'134', b'1a3678', b'1ab5689'])
testfilefixup(case4, b'aa2bcd8ee', [b'', b'aa34', b'aa23d78', b'aa2bcd8ee'])
testfilefixup(case4, b'aa2bcdd8ee', [b'', b'aa34', b'aa23678', b'aa24568ee'])
testfilefixup(case4, b'aaaaaa', case4)
testfilefixup(case4, b'aa258b', [b'', b'aa34', b'aa2378', b'aa258b'])
testfilefixup(case4, b'25bb', [b'', b'34', b'23678', b'25689'])
testfilefixup(case4, b'27', [b'', b'34', b'23678', b'245689'])
testfilefixup(case4, b'28', [b'', b'34', b'2378', b'28'])
testfilefixup(case4, b'', [b'', b'34', b'37', b''])

# input case 5: replace a small chunk which is near a deleted line
case5 = buildcontents([(b'12', [1, 2]), (b'3', [1]), (b'4', [1, 2]),])

testfilefixup(case5, b'1cd4', [b'', b'1cd34', b'1cd4'])

# input case 6: base "changeset" is immutable
case6 = [b'1357', b'0125678']

testfilefixup(case6, b'0125678', case6)
testfilefixup(case6, b'0a25678', case6)
testfilefixup(case6, b'0a256b8', case6)
testfilefixup(case6, b'abcdefg', [b'1357', b'a1c5e7g'])
testfilefixup(case6, b'abcdef', case6)
testfilefixup(case6, b'', [b'1357', b'157'])
testfilefixup(case6, b'0123456789', [b'1357', b'0123456789'])

# input case 7: change an empty file
case7 = [b'']

testfilefixup(case7, b'1', case7)