~bzr-pqm/bzr/bzr.dev

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
# Copyright (C) 2005-2011, 2016 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, write to the Free Software
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA

import os
import stat
import time

from bzrlib import osutils
from bzrlib.errors import BzrError
from bzrlib.hashcache import HashCache
from bzrlib.tests import (
    TestCaseInTempDir,
    )
from bzrlib.tests.features import (
    OsFifoFeature,
    )


sha1 = osutils.sha_string


def pause():
    time.sleep(5.0)


class TestHashCache(TestCaseInTempDir):
    """Test the hashcache against a real directory"""

    def make_hashcache(self):
        # make a dummy bzr directory just to hold the cache
        os.mkdir('.bzr')
        hc = HashCache('.', '.bzr/stat-cache')
        return hc

    def reopen_hashcache(self):
        hc = HashCache('.', '.bzr/stat-cache')
        hc.read()
        return hc

    def test_hashcache_initial_miss(self):
        """Get correct hash from an empty hashcache"""
        hc = self.make_hashcache()
        self.build_tree_contents([('foo', 'hello')])
        self.assertEqual(hc.get_sha1('foo'),
                          'aaf4c61ddcc5e8a2dabede0f3b482cd9aea9434d')
        self.assertEqual(hc.miss_count, 1)
        self.assertEqual(hc.hit_count, 0)

    def test_hashcache_new_file(self):
        hc = self.make_hashcache()
        self.build_tree_contents([('foo', 'goodbye')])
        # now read without pausing; it may not be possible to cache it as its
        # so new
        self.assertEqual(hc.get_sha1('foo'), sha1('goodbye'))

    def test_hashcache_nonexistent_file(self):
        hc = self.make_hashcache()
        self.assertEqual(hc.get_sha1('no-name-yet'), None)

    def test_hashcache_replaced_file(self):
        hc = self.make_hashcache()
        self.build_tree_contents([('foo', 'goodbye')])
        self.assertEqual(hc.get_sha1('foo'), sha1('goodbye'))
        os.remove('foo')
        self.assertEqual(hc.get_sha1('foo'), None)
        self.build_tree_contents([('foo', 'new content')])
        self.assertEqual(hc.get_sha1('foo'), sha1('new content'))

    def test_hashcache_not_file(self):
        hc = self.make_hashcache()
        self.build_tree(['subdir/'])
        self.assertEqual(hc.get_sha1('subdir'), None)

    def test_hashcache_load(self):
        hc = self.make_hashcache()
        self.build_tree_contents([('foo', 'contents')])
        pause()
        self.assertEqual(hc.get_sha1('foo'), sha1('contents'))
        hc.write()
        hc = self.reopen_hashcache()
        self.assertEqual(hc.get_sha1('foo'), sha1('contents'))
        self.assertEqual(hc.hit_count, 1)

    def test_hammer_hashcache(self):
        hc = self.make_hashcache()
        for i in xrange(10000):
            self.log('start writing at %s', time.time())
            f = file('foo', 'w')
            try:
                last_content = '%08x' % i
                f.write(last_content)
            finally:
                f.close()
            last_sha1 = sha1(last_content)
            self.log("iteration %d: %r -> %r",
                     i, last_content, last_sha1)
            got_sha1 = hc.get_sha1('foo')
            self.assertEqual(got_sha1, last_sha1)
            hc.write()
            hc = self.reopen_hashcache()

    def test_hashcache_raise(self):
        """check that hashcache can raise BzrError"""
        self.requireFeature(OsFifoFeature)
        hc = self.make_hashcache()
        os.mkfifo('a')
        # It's possible that the system supports fifos but the filesystem
        # can't.  In that case we should skip at this point.  But in fact
        # such combinations don't usually occur for the filesystem where
        # people test bzr.
        self.assertRaises(BzrError, hc.get_sha1, 'a')


class FakeHashCache(HashCache):
    """Hashcache that consults a fake clock rather than the real one.

    This lets us examine how old or new files would be handled, without
    actually having to wait for time to pass.
    """
    def __init__(self):
        # set root and cache file name to none to make sure we won't touch the
        # real filesystem
        HashCache.__init__(self, '.', 'hashcache')
        self._files = {}
        # simulated clock running forward as operations happen
        self._clock = 0

    def put_file(self, filename, file_contents):
        abspath = './' + filename
        self._files[abspath] = (file_contents, self._clock)

    def _fingerprint(self, abspath, fs=None):
        entry = self._files[abspath]
        return (len(entry[0]),
                entry[1], entry[1],
                10, 20,
                stat.S_IFREG | 0600)

    def _really_sha1_file(self, abspath, filters):
        if abspath in self._files:
            return sha1(self._files[abspath][0])
        else:
            return None

    def _cutoff_time(self):
        return self._clock - 2

    def pretend_to_sleep(self, secs):
        self._clock += secs


class TestHashCacheFakeFilesystem(TestCaseInTempDir):
    """Tests the hashcache using a simulated OS.
    """

    def make_hashcache(self):
        return FakeHashCache()

    def test_hashcache_miss_new_file(self):
        """A new file gives the right sha1 but misses"""
        hc = self.make_hashcache()
        hc.put_file('foo', 'hello')
        self.assertEqual(hc.get_sha1('foo'), sha1('hello'))
        self.assertEqual(hc.miss_count, 1)
        self.assertEqual(hc.hit_count, 0)
        # if we try again it's still too new;
        self.assertEqual(hc.get_sha1('foo'), sha1('hello'))
        self.assertEqual(hc.miss_count, 2)
        self.assertEqual(hc.hit_count, 0)

    def test_hashcache_old_file(self):
        """An old file gives the right sha1 and hits"""
        hc = self.make_hashcache()
        hc.put_file('foo', 'hello')
        hc.pretend_to_sleep(20)
        # file is new; should get the correct hash but miss
        self.assertEqual(hc.get_sha1('foo'), sha1('hello'))
        self.assertEqual(hc.miss_count, 1)
        self.assertEqual(hc.hit_count, 0)
        # and can now be hit
        self.assertEqual(hc.get_sha1('foo'), sha1('hello'))
        self.assertEqual(hc.miss_count, 1)
        self.assertEqual(hc.hit_count, 1)
        hc.pretend_to_sleep(3)
        # and again
        self.assertEqual(hc.get_sha1('foo'), sha1('hello'))
        self.assertEqual(hc.miss_count, 1)
        self.assertEqual(hc.hit_count, 2)

    def test_hashcache_invalidates(self):
        hc = self.make_hashcache()
        hc.put_file('foo', 'hello')
        hc.pretend_to_sleep(20)
        hc.get_sha1('foo')
        hc.put_file('foo', 'h1llo')
        self.assertEqual(hc.get_sha1('foo'), sha1('h1llo'))
        self.assertEqual(hc.miss_count, 2)
        self.assertEqual(hc.hit_count, 0)