view tests/test-bdiff.py @ 32226:bf3af0eced44

fsmonitor: do not nuke dirstate filecache

In the future, chg may prefill repo's dirstate filecache so it's valuable
and should be kept. Previously we drop both filecache and property cache for
dirstate during fsmonitor reposetup, this patch changes it to only drop
property cache but keep the filecache.

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__)