1 # Copyright (C) 2006, 2008 Canonical Ltd
3 # Dulwich is dual-licensed under the Apache License, Version 2.0 and the GNU
4 # General Public License as public by the Free Software Foundation; version 2.0
5 # or (at your option) any later version. You can redistribute it and/or
6 # modify it under the terms of either of these two licenses.
8 # Unless required by applicable law or agreed to in writing, software
9 # distributed under the License is distributed on an "AS IS" BASIS,
10 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
11 # See the License for the specific language governing permissions and
12 # limitations under the License.
14 # You should have received a copy of the licenses; if not, see
15 # <http://www.gnu.org/licenses/> for a copy of the GNU General Public License
16 # and <http://www.apache.org/licenses/LICENSE-2.0> for a copy of the Apache
17 # License, Version 2.0.
20 """Tests for the lru_cache module."""
25 from dulwich.tests import (
30 class TestLRUCache(TestCase):
31 """Test that LRU cache properly keeps track of entries."""
33 def test_cache_size(self):
34 cache = lru_cache.LRUCache(max_cache=10)
35 self.assertEqual(10, cache.cache_size())
37 cache = lru_cache.LRUCache(max_cache=256)
38 self.assertEqual(256, cache.cache_size())
41 self.assertEqual(512, cache.cache_size())
43 def test_missing(self):
44 cache = lru_cache.LRUCache(max_cache=10)
46 self.assertFalse('foo' in cache)
47 self.assertRaises(KeyError, cache.__getitem__, 'foo')
50 self.assertEqual('bar', cache['foo'])
51 self.assertTrue('foo' in cache)
52 self.assertFalse('bar' in cache)
54 def test_map_None(self):
55 # Make sure that we can properly map None as a key.
56 cache = lru_cache.LRUCache(max_cache=10)
57 self.assertFalse(None in cache)
59 self.assertEqual(1, cache[None])
61 self.assertEqual(2, cache[None])
62 # Test the various code paths of __getitem__, to make sure that we can
63 # handle when None is the key for the LRU and the MRU
69 self.assertEqual([None, 1], [n.key for n in cache._walk_lru()])
71 def test_add__null_key(self):
72 cache = lru_cache.LRUCache(max_cache=10)
73 self.assertRaises(ValueError, cache.add, lru_cache._null_key, 1)
75 def test_overflow(self):
76 """Adding extra entries will pop out old ones."""
77 cache = lru_cache.LRUCache(max_cache=1, after_cleanup_count=1)
80 # With a max cache of 1, adding 'baz' should pop out 'foo'
83 self.assertFalse('foo' in cache)
84 self.assertTrue('baz' in cache)
86 self.assertEqual('biz', cache['baz'])
88 def test_by_usage(self):
89 """Accessing entries bumps them up in priority."""
90 cache = lru_cache.LRUCache(max_cache=2)
95 self.assertEqual('biz', cache['baz'])
97 # This must kick out 'foo' because it was the last accessed
100 self.assertFalse('foo' in cache)
102 def test_cleanup(self):
103 """Test that we can use a cleanup function."""
106 def cleanup_func(key, val):
107 cleanup_called.append((key, val))
109 cache = lru_cache.LRUCache(max_cache=2, after_cleanup_count=2)
111 cache.add('baz', '1', cleanup=cleanup_func)
112 cache.add('foo', '2', cleanup=cleanup_func)
113 cache.add('biz', '3', cleanup=cleanup_func)
115 self.assertEqual([('baz', '1')], cleanup_called)
117 # 'foo' is now most recent, so final cleanup will call it last
120 self.assertEqual([('baz', '1'), ('biz', '3'), ('foo', '2')],
123 def test_cleanup_on_replace(self):
124 """Replacing an object should cleanup the old value."""
127 def cleanup_func(key, val):
128 cleanup_called.append((key, val))
130 cache = lru_cache.LRUCache(max_cache=2)
131 cache.add(1, 10, cleanup=cleanup_func)
132 cache.add(2, 20, cleanup=cleanup_func)
133 cache.add(2, 25, cleanup=cleanup_func)
135 self.assertEqual([(2, 20)], cleanup_called)
136 self.assertEqual(25, cache[2])
138 # Even __setitem__ should make sure cleanup() is called
140 self.assertEqual([(2, 20), (2, 25)], cleanup_called)
143 cache = lru_cache.LRUCache(max_cache=10, after_cleanup_count=10)
150 self.assertEqual(4, len(cache))
157 self.assertEqual(8, len(cache))
159 cache[1] = 15 # replacement
161 self.assertEqual(8, len(cache))
168 self.assertEqual(10, len(cache))
169 self.assertEqual([11, 10, 9, 1, 8, 7, 6, 5, 4, 3],
170 [n.key for n in cache._walk_lru()])
172 def test_cleanup_shrinks_to_after_clean_count(self):
173 cache = lru_cache.LRUCache(max_cache=5, after_cleanup_count=3)
181 self.assertEqual(5, len(cache))
182 # This will bump us over the max, which causes us to shrink down to
183 # after_cleanup_cache size
185 self.assertEqual(3, len(cache))
187 def test_after_cleanup_larger_than_max(self):
188 cache = lru_cache.LRUCache(max_cache=5, after_cleanup_count=10)
189 self.assertEqual(5, cache._after_cleanup_count)
191 def test_after_cleanup_none(self):
192 cache = lru_cache.LRUCache(max_cache=5, after_cleanup_count=None)
193 # By default _after_cleanup_size is 80% of the normal size
194 self.assertEqual(4, cache._after_cleanup_count)
196 def test_cleanup_2(self):
197 cache = lru_cache.LRUCache(max_cache=5, after_cleanup_count=2)
206 self.assertEqual(5, len(cache))
209 self.assertEqual(2, len(cache))
211 def test_preserve_last_access_order(self):
212 cache = lru_cache.LRUCache(max_cache=5)
221 self.assertEqual([5, 4, 3, 2, 1], [n.key for n in cache._walk_lru()])
223 # Now access some randomly
228 self.assertEqual([2, 3, 5, 4, 1], [n.key for n in cache._walk_lru()])
231 cache = lru_cache.LRUCache(max_cache=5)
235 self.assertEqual(20, cache.get(2))
236 self.assertEqual(None, cache.get(3))
238 self.assertTrue(obj is cache.get(3, obj))
239 self.assertEqual([2, 1], [n.key for n in cache._walk_lru()])
240 self.assertEqual(10, cache.get(1))
241 self.assertEqual([1, 2], [n.key for n in cache._walk_lru()])
244 cache = lru_cache.LRUCache(max_cache=5, after_cleanup_count=5)
249 self.assertEqual([1, 2, 3], sorted(cache.keys()))
253 self.assertEqual([2, 3, 4, 5, 6], sorted(cache.keys()))
255 def test_resize_smaller(self):
256 cache = lru_cache.LRUCache(max_cache=5, after_cleanup_count=4)
262 self.assertEqual([1, 2, 3, 4, 5], sorted(cache.keys()))
264 self.assertEqual([3, 4, 5, 6], sorted(cache.keys()))
265 # Now resize to something smaller, which triggers a cleanup
266 cache.resize(max_cache=3, after_cleanup_count=2)
267 self.assertEqual([5, 6], sorted(cache.keys()))
268 # Adding something will use the new size
270 self.assertEqual([5, 6, 7], sorted(cache.keys()))
272 self.assertEqual([7, 8], sorted(cache.keys()))
274 def test_resize_larger(self):
275 cache = lru_cache.LRUCache(max_cache=5, after_cleanup_count=4)
281 self.assertEqual([1, 2, 3, 4, 5], sorted(cache.keys()))
283 self.assertEqual([3, 4, 5, 6], sorted(cache.keys()))
284 cache.resize(max_cache=8, after_cleanup_count=6)
285 self.assertEqual([3, 4, 5, 6], sorted(cache.keys()))
290 self.assertEqual([3, 4, 5, 6, 7, 8, 9, 10], sorted(cache.keys()))
291 cache[11] = 12 # triggers cleanup back to new after_cleanup_count
292 self.assertEqual([6, 7, 8, 9, 10, 11], sorted(cache.keys()))
295 class TestLRUSizeCache(TestCase):
297 def test_basic_init(self):
298 cache = lru_cache.LRUSizeCache()
299 self.assertEqual(2048, cache._max_cache)
300 self.assertEqual(int(cache._max_size*0.8), cache._after_cleanup_size)
301 self.assertEqual(0, cache._value_size)
303 def test_add__null_key(self):
304 cache = lru_cache.LRUSizeCache()
305 self.assertRaises(ValueError, cache.add, lru_cache._null_key, 1)
307 def test_add_tracks_size(self):
308 cache = lru_cache.LRUSizeCache()
309 self.assertEqual(0, cache._value_size)
310 cache.add('my key', 'my value text')
311 self.assertEqual(13, cache._value_size)
313 def test_remove_tracks_size(self):
314 cache = lru_cache.LRUSizeCache()
315 self.assertEqual(0, cache._value_size)
316 cache.add('my key', 'my value text')
317 self.assertEqual(13, cache._value_size)
318 node = cache._cache['my key']
319 cache._remove_node(node)
320 self.assertEqual(0, cache._value_size)
322 def test_no_add_over_size(self):
323 """Adding a large value may not be cached at all."""
324 cache = lru_cache.LRUSizeCache(max_size=10, after_cleanup_size=5)
325 self.assertEqual(0, cache._value_size)
326 self.assertEqual({}, cache.items())
327 cache.add('test', 'key')
328 self.assertEqual(3, cache._value_size)
329 self.assertEqual({'test': 'key'}, cache.items())
330 cache.add('test2', 'key that is too big')
331 self.assertEqual(3, cache._value_size)
332 self.assertEqual({'test': 'key'}, cache.items())
333 # If we would add a key, only to cleanup and remove all cached entries,
334 # then obviously that value should not be stored
335 cache.add('test3', 'bigkey')
336 self.assertEqual(3, cache._value_size)
337 self.assertEqual({'test': 'key'}, cache.items())
339 cache.add('test4', 'bikey')
340 self.assertEqual(3, cache._value_size)
341 self.assertEqual({'test': 'key'}, cache.items())
343 def test_no_add_over_size_cleanup(self):
344 """If a large value is not cached, we will call cleanup right away."""
347 def cleanup(key, value):
348 cleanup_calls.append((key, value))
350 cache = lru_cache.LRUSizeCache(max_size=10, after_cleanup_size=5)
351 self.assertEqual(0, cache._value_size)
352 self.assertEqual({}, cache.items())
353 cache.add('test', 'key that is too big', cleanup=cleanup)
355 self.assertEqual(0, cache._value_size)
356 self.assertEqual({}, cache.items())
357 # and cleanup was called
358 self.assertEqual([('test', 'key that is too big')], cleanup_calls)
360 def test_adding_clears_cache_based_on_size(self):
361 """The cache is cleared in LRU order until small enough"""
362 cache = lru_cache.LRUSizeCache(max_size=20)
363 cache.add('key1', 'value') # 5 chars
364 cache.add('key2', 'value2') # 6 chars
365 cache.add('key3', 'value23') # 7 chars
366 self.assertEqual(5+6+7, cache._value_size)
367 cache['key2'] # reference key2 so it gets a newer reference time
368 cache.add('key4', 'value234') # 8 chars, over limit
369 # We have to remove 2 keys to get back under limit
370 self.assertEqual(6+8, cache._value_size)
371 self.assertEqual({'key2': 'value2', 'key4': 'value234'},
374 def test_adding_clears_to_after_cleanup_size(self):
375 cache = lru_cache.LRUSizeCache(max_size=20, after_cleanup_size=10)
376 cache.add('key1', 'value') # 5 chars
377 cache.add('key2', 'value2') # 6 chars
378 cache.add('key3', 'value23') # 7 chars
379 self.assertEqual(5+6+7, cache._value_size)
380 cache['key2'] # reference key2 so it gets a newer reference time
381 cache.add('key4', 'value234') # 8 chars, over limit
382 # We have to remove 3 keys to get back under limit
383 self.assertEqual(8, cache._value_size)
384 self.assertEqual({'key4': 'value234'}, cache.items())
386 def test_custom_sizes(self):
387 def size_of_list(lst):
388 return sum(len(x) for x in lst)
389 cache = lru_cache.LRUSizeCache(max_size=20, after_cleanup_size=10,
390 compute_size=size_of_list)
392 cache.add('key1', ['val', 'ue']) # 5 chars
393 cache.add('key2', ['val', 'ue2']) # 6 chars
394 cache.add('key3', ['val', 'ue23']) # 7 chars
395 self.assertEqual(5+6+7, cache._value_size)
396 cache['key2'] # reference key2 so it gets a newer reference time
397 cache.add('key4', ['value', '234']) # 8 chars, over limit
398 # We have to remove 3 keys to get back under limit
399 self.assertEqual(8, cache._value_size)
400 self.assertEqual({'key4': ['value', '234']}, cache.items())
402 def test_cleanup(self):
403 cache = lru_cache.LRUSizeCache(max_size=20, after_cleanup_size=10)
406 cache.add('key1', 'value') # 5 chars
407 cache.add('key2', 'value2') # 6 chars
408 cache.add('key3', 'value23') # 7 chars
409 self.assertEqual(5+6+7, cache._value_size)
412 # Only the most recent fits after cleaning up
413 self.assertEqual(7, cache._value_size)
416 cache = lru_cache.LRUSizeCache(max_size=10)
421 self.assertEqual([1, 2, 3], sorted(cache.keys()))
423 def test_resize_smaller(self):
424 cache = lru_cache.LRUSizeCache(max_size=10, after_cleanup_size=9)
430 self.assertEqual([2, 3, 4], sorted(cache.keys()))
431 # Resize should also cleanup again
432 cache.resize(max_size=6, after_cleanup_size=4)
433 self.assertEqual([4], sorted(cache.keys()))
434 # Adding should use the new max size
436 self.assertEqual([4, 5], sorted(cache.keys()))
438 self.assertEqual([6], sorted(cache.keys()))
440 def test_resize_larger(self):
441 cache = lru_cache.LRUSizeCache(max_size=10, after_cleanup_size=9)
447 self.assertEqual([2, 3, 4], sorted(cache.keys()))
448 cache.resize(max_size=15, after_cleanup_size=12)
449 self.assertEqual([2, 3, 4], sorted(cache.keys()))
452 self.assertEqual([2, 3, 4, 5, 6], sorted(cache.keys()))
454 self.assertEqual([4, 5, 6, 7], sorted(cache.keys()))