Mercurial > hg
view tests/test-bdiff.py @ 50346:54f68495ab2a stable
revlog-split: show manifest data loss situation when using clonebundle
After the commit of the transaction from applying the clone bundle, changes to
the manifest from the subsequent pull would write index data in the wrong file.
This lead to data being "lost" after the pull and the repository to be
corrupted. We add a test checking this specific scenario.
In practice, the issue only affects the manifest but we also test the issue with a file for future proofing things up.
See test documentation and failure for details.
author | Pierre-Yves David <pierre-yves.david@octobus.net> |
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date | Tue, 18 Apr 2023 01:12:00 +0200 |
parents | 6000f5b25c9b |
children |
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import collections import struct import unittest from mercurial import mdiff class diffreplace(collections.namedtuple('diffreplace', 'start end from_ to')): def __repr__(self): return 'diffreplace(%r, %r, %r, %r)' % self class BdiffTests(unittest.TestCase): def assert_bdiff_applies(self, a, b): d = mdiff.textdiff(a, b) c = a if d: c = mdiff.patches(a, [d]) self.assertEqual( c, b, ( "bad diff+patch result from\n %r to\n " "%r: \nbdiff: %r\npatched: %r" % (a, b, d, c[:200]) ), ) def assert_bdiff(self, a, b): self.assert_bdiff_applies(a, b) self.assert_bdiff_applies(b, a) def test_bdiff_basic(self): cases = [ (b"a\nc\n\n\n\n", b"a\nb\n\n\n"), (b"a\nb\nc\n", b"a\nc\n"), (b"", b""), (b"a\nb\nc", b"a\nb\nc"), (b"a\nb\nc\nd\n", b"a\nd\n"), (b"a\nb\nc\nd\n", b"a\nc\ne\n"), (b"a\nb\nc\n", b"a\nc\n"), (b"a\n", b"c\na\nb\n"), (b"a\n", b""), (b"a\n", b"b\nc\n"), (b"a\n", b"c\na\n"), (b"", b"adjfkjdjksdhfksj"), (b"", b"ab"), (b"", b"abc"), (b"a", b"a"), (b"ab", b"ab"), (b"abc", b"abc"), (b"a\n", b"a\n"), (b"a\nb", b"a\nb"), ] for a, b in cases: self.assert_bdiff(a, b) def showdiff(self, a, b): bin = mdiff.textdiff(a, b) pos = 0 q = 0 actions = [] while pos < len(bin): p1, p2, l = struct.unpack(">lll", bin[pos : pos + 12]) pos += 12 if p1: actions.append(a[q:p1]) actions.append(diffreplace(p1, p2, a[p1:p2], bin[pos : pos + l])) pos += l q = p2 if q < len(a): actions.append(a[q:]) return actions def test_issue1295(self): cases = [ ( b"x\n\nx\n\nx\n\nx\n\nz\n", b"x\n\nx\n\ny\n\nx\n\nx\n\nz\n", [ b'x\n\nx\n\n', diffreplace(6, 6, b'', b'y\n\n'), b'x\n\nx\n\nz\n', ], ), ( b"x\n\nx\n\nx\n\nx\n\nz\n", b"x\n\nx\n\ny\n\nx\n\ny\n\nx\n\nz\n", [ b'x\n\nx\n\n', diffreplace(6, 6, b'', b'y\n\n'), b'x\n\n', diffreplace(9, 9, b'', b'y\n\n'), b'x\n\nz\n', ], ), ] for old, new, want in cases: self.assertEqual(self.showdiff(old, new), want) def test_issue1295_varies_on_pure(self): # we should pick up abbbc. rather than bc.de as the longest match got = self.showdiff( b"a\nb\nb\nb\nc\n.\nd\ne\n.\nf\n", b"a\nb\nb\na\nb\nb\nb\nc\n.\nb\nc\n.\nd\ne\nf\n", ) want_c = [ b'a\nb\nb\n', diffreplace(6, 6, b'', b'a\nb\nb\nb\nc\n.\n'), b'b\nc\n.\nd\ne\n', diffreplace(16, 18, b'.\n', b''), b'f\n', ] want_pure = [ diffreplace(0, 0, b'', b'a\nb\nb\n'), b'a\nb\nb\nb\nc\n.\n', diffreplace(12, 12, b'', b'b\nc\n.\n'), b'd\ne\n', diffreplace(16, 18, b'.\n', b''), b'f\n', ] self.assertTrue( got in (want_c, want_pure), 'got: %r, wanted either %r or %r' % (got, want_c, want_pure), ) def test_fixws(self): cases = [ (b" \ta\r b\t\n", b"ab\n", 1), (b" \ta\r b\t\n", b" a b\n", 0), (b"", b"", 1), (b"", b"", 0), ] for a, b, allws in cases: c = mdiff.fixws(a, allws) self.assertEqual( c, b, 'fixws(%r) want %r got %r (allws=%r)' % (a, b, c, allws) ) def test_nice_diff_for_trivial_change(self): self.assertEqual( self.showdiff( b''.join(b'<%d\n-\n' % i for i in range(5)), b''.join(b'>%d\n-\n' % i for i in range(5)), ), [ diffreplace(0, 3, b'<0\n', b'>0\n'), b'-\n', diffreplace(5, 8, b'<1\n', b'>1\n'), b'-\n', diffreplace(10, 13, b'<2\n', b'>2\n'), b'-\n', diffreplace(15, 18, b'<3\n', b'>3\n'), b'-\n', diffreplace(20, 23, b'<4\n', b'>4\n'), b'-\n', ], ) def test_prefer_appending(self): # 1 line to 3 lines self.assertEqual( self.showdiff(b'a\n', b'a\n' * 3), [b'a\n', diffreplace(2, 2, b'', b'a\na\n')], ) # 1 line to 5 lines self.assertEqual( self.showdiff(b'a\n', b'a\n' * 5), [b'a\n', diffreplace(2, 2, b'', b'a\na\na\na\n')], ) def test_prefer_removing_trailing(self): # 3 lines to 1 line self.assertEqual( self.showdiff(b'a\n' * 3, b'a\n'), [b'a\n', diffreplace(2, 6, b'a\na\n', b'')], ) # 5 lines to 1 line self.assertEqual( self.showdiff(b'a\n' * 5, b'a\n'), [b'a\n', diffreplace(2, 10, b'a\na\na\na\n', b'')], ) if __name__ == '__main__': import silenttestrunner silenttestrunner.main(__name__)