view tests/test-bdiff.py @ 36611:6906547c8476

wireproto: don't expose legacy commands to version 2 of wire protocol

Now that we have the ability to control which transports a wire
protocol command is exposed on, let's put it to use.

We flag the "branches," "changegroup," and "changegroupsubset"
commands as only available on version 1. "branches" was used by the
legacy discovery mechanism and was replaced by the "known" and
"heads" commands. "changegroup" and "changegroupsubset" were
replaced by "getbundle."

"between" is also legacy. However, since it is used by the SSH
handshake protocol, marking it as legacy is a bit more complicated
and will be done in a later commit.

Another nuanced issue with this change is that the server-advertised
capabilities still list "changegroupsubset" despite the command not
being available. This will be addressed in a subsequent commit.

Differential Revision: https://phab.mercurial-scm.org/D2485

from __future__ import absolute_import, print_function
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 = [
            ("a\nc\n\n\n\n", "a\nb\n\n\n"),
            ("a\nb\nc\n", "a\nc\n"),
            ("", ""),
            ("a\nb\nc", "a\nb\nc"),
            ("a\nb\nc\nd\n", "a\nd\n"),
            ("a\nb\nc\nd\n", "a\nc\ne\n"),
            ("a\nb\nc\n", "a\nc\n"),
            ("a\n", "c\na\nb\n"),
            ("a\n", ""),
            ("a\n", "b\nc\n"),
            ("a\n", "c\na\n"),
            ("", "adjfkjdjksdhfksj"),
            ("", "ab"),
            ("", "abc"),
            ("a", "a"),
            ("ab", "ab"),
            ("abc", "abc"),
            ("a\n", "a\n"),
            ("a\nb", "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 = [
            ("x\n\nx\n\nx\n\nx\n\nz\n", "x\n\nx\n\ny\n\nx\n\nx\n\nz\n",
             ['x\n\nx\n\n', diffreplace(6, 6, '', 'y\n\n'), 'x\n\nx\n\nz\n']),
            ("x\n\nx\n\nx\n\nx\n\nz\n", "x\n\nx\n\ny\n\nx\n\ny\n\nx\n\nz\n",
             ['x\n\nx\n\n',
              diffreplace(6, 6, '', 'y\n\n'),
              'x\n\n',
              diffreplace(9, 9, '', 'y\n\n'),
              '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("a\nb\nb\nb\nc\n.\nd\ne\n.\nf\n",
                            "a\nb\nb\na\nb\nb\nb\nc\n.\nb\nc\n.\nd\ne\nf\n")
        want_c = ['a\nb\nb\n',
                  diffreplace(6, 6, '', 'a\nb\nb\nb\nc\n.\n'),
                  'b\nc\n.\nd\ne\n',
                  diffreplace(16, 18, '.\n', ''),
                  'f\n']
        want_pure = [diffreplace(0, 0, '', 'a\nb\nb\n'),
                     'a\nb\nb\nb\nc\n.\n',
                     diffreplace(12, 12, '', 'b\nc\n.\n'),
                     'd\ne\n',
                     diffreplace(16, 18, '.\n', ''), 'f\n']
        self.assert_(got in (want_c, want_pure),
                     'got: %r, wanted either %r or %r' % (
                         got, want_c, want_pure))

    def test_fixws(self):
        cases = [
            (" \ta\r b\t\n", "ab\n", 1),
            (" \ta\r b\t\n", " a b\n", 0),
            ("", "", 1),
            ("", "", 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(
            ''.join('<%s\n-\n' % i for i in range(5)),
            ''.join('>%s\n-\n' % i for i in range(5))),
                         [diffreplace(0, 3, '<0\n', '>0\n'),
                          '-\n',
                          diffreplace(5, 8, '<1\n', '>1\n'),
                          '-\n',
                          diffreplace(10, 13, '<2\n', '>2\n'),
                          '-\n',
                          diffreplace(15, 18, '<3\n', '>3\n'),
                          '-\n',
                          diffreplace(20, 23, '<4\n', '>4\n'),
                          '-\n'])

    def test_prefer_appending(self):
        # 1 line to 3 lines
        self.assertEqual(self.showdiff('a\n', 'a\n' * 3),
                         ['a\n', diffreplace(2, 2, '', 'a\na\n')])
        # 1 line to 5 lines
        self.assertEqual(self.showdiff('a\n', 'a\n' * 5),
                         ['a\n', diffreplace(2, 2, '', 'a\na\na\na\n')])

    def test_prefer_removing_trailing(self):
        # 3 lines to 1 line
        self.assertEqual(self.showdiff('a\n' * 3, 'a\n'),
                         ['a\n', diffreplace(2, 6, 'a\na\n', '')])
        # 5 lines to 1 line
        self.assertEqual(self.showdiff('a\n' * 5, 'a\n'),
                         ['a\n', diffreplace(2, 10, 'a\na\na\na\n', '')])

if __name__ == '__main__':
    import silenttestrunner
    silenttestrunner.main(__name__)