1 files changed, 435 insertions, 0 deletions
diff --git a/bzrlib/tests/test_lru_cache.py b/bzrlib/tests/test_lru_cache.py
new file mode 100644
index 0000000..8b38583
--- /dev/null
+++ b/bzrlib/tests/test_lru_cache.py
@@ -0,0 +1,435 @@
+# Copyright (C) 2006, 2008, 2009 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
+
+"""Tests for the lru_cache module."""
+
+from bzrlib import (
+    lru_cache,
+    symbol_versioning,
+    tests,
+    )
+
+
+def walk_lru(lru):
+    """Test helper to walk the LRU list and assert its consistency"""
+    node = lru._most_recently_used
+    if node is not None:
+        if node.prev is not None:
+            raise AssertionError('the _most_recently_used entry is not'
+                                 ' supposed to have a previous entry'
+                                 ' %s' % (node,))
+    while node is not None:
+        if node.next_key is lru_cache._null_key:
+            if node is not lru._least_recently_used:
+                raise AssertionError('only the last node should have'
+                                     ' no next value: %s' % (node,))
+            node_next = None
+        else:
+            node_next = lru._cache[node.next_key]
+            if node_next.prev is not node:
+                raise AssertionError('inconsistency found, node.next.prev'
+                                     ' != node: %s' % (node,))
+        if node.prev is None:
+            if node is not lru._most_recently_used:
+                raise AssertionError('only the _most_recently_used should'
+                                     ' not have a previous node: %s'
+                                     % (node,))
+        else:
+            if node.prev.next_key != node.key:
+                raise AssertionError('inconsistency found, node.prev.next'
+                                     ' != node: %s' % (node,))
+        yield node
+        node = node_next
+
+ 
+class TestLRUCache(tests.TestCase):
+    """Test that LRU cache properly keeps track of entries."""
+
+    def test_cache_size(self):
+        cache = lru_cache.LRUCache(max_cache=10)
+        self.assertEqual(10, cache.cache_size())
+
+        cache = lru_cache.LRUCache(max_cache=256)
+        self.assertEqual(256, cache.cache_size())
+
+        cache.resize(512)
+        self.assertEqual(512, cache.cache_size())
+
+    def test_missing(self):
+        cache = lru_cache.LRUCache(max_cache=10)
+
+        self.assertFalse('foo' in cache)
+        self.assertRaises(KeyError, cache.__getitem__, 'foo')
+
+        cache['foo'] = 'bar'
+        self.assertEqual('bar', cache['foo'])
+        self.assertTrue('foo' in cache)
+        self.assertFalse('bar' in cache)
+
+    def test_map_None(self):
+        # Make sure that we can properly map None as a key.
+        cache = lru_cache.LRUCache(max_cache=10)
+        self.assertFalse(None in cache)
+        cache[None] = 1
+        self.assertEqual(1, cache[None])
+        cache[None] = 2
+        self.assertEqual(2, cache[None])
+        # Test the various code paths of __getitem__, to make sure that we can
+        # handle when None is the key for the LRU and the MRU
+        cache[1] = 3
+        cache[None] = 1
+        cache[None]
+        cache[1]
+        cache[None]
+        self.assertEqual([None, 1], [n.key for n in walk_lru(cache)])
+
+    def test_add__null_key(self):
+        cache = lru_cache.LRUCache(max_cache=10)
+        self.assertRaises(ValueError,
+            cache.__setitem__, lru_cache._null_key, 1)
+
+    def test_overflow(self):
+        """Adding extra entries will pop out old ones."""
+        cache = lru_cache.LRUCache(max_cache=1, after_cleanup_count=1)
+
+        cache['foo'] = 'bar'
+        # With a max cache of 1, adding 'baz' should pop out 'foo'
+        cache['baz'] = 'biz'
+
+        self.assertFalse('foo' in cache)
+        self.assertTrue('baz' in cache)
+
+        self.assertEqual('biz', cache['baz'])
+
+    def test_by_usage(self):
+        """Accessing entries bumps them up in priority."""
+        cache = lru_cache.LRUCache(max_cache=2)
+
+        cache['baz'] = 'biz'
+        cache['foo'] = 'bar'
+
+        self.assertEqual('biz', cache['baz'])
+
+        # This must kick out 'foo' because it was the last accessed
+        cache['nub'] = 'in'
+
+        self.assertFalse('foo' in cache)
+
+    def test_cleanup_function_deprecated(self):
+        """Test that per-node cleanup functions are no longer allowed"""
+        cache = lru_cache.LRUCache()
+        self.assertRaises(ValueError, self.applyDeprecated,
+            symbol_versioning.deprecated_in((2, 5, 0)),
+            cache.add, "key", 1, cleanup=lambda: None)
+
+    def test_len(self):
+        cache = lru_cache.LRUCache(max_cache=10, after_cleanup_count=10)
+
+        cache[1] = 10
+        cache[2] = 20
+        cache[3] = 30
+        cache[4] = 40
+
+        self.assertEqual(4, len(cache))
+
+        cache[5] = 50
+        cache[6] = 60
+        cache[7] = 70
+        cache[8] = 80
+
+        self.assertEqual(8, len(cache))
+
+        cache[1] = 15 # replacement
+
+        self.assertEqual(8, len(cache))
+
+        cache[9] = 90
+        cache[10] = 100
+        cache[11] = 110
+
+        # We hit the max
+        self.assertEqual(10, len(cache))
+        self.assertEqual([11, 10, 9, 1, 8, 7, 6, 5, 4, 3],
+                         [n.key for n in walk_lru(cache)])
+
+    def test_cleanup_shrinks_to_after_clean_count(self):
+        cache = lru_cache.LRUCache(max_cache=5, after_cleanup_count=3)
+
+        cache[1] = 10
+        cache[2] = 20
+        cache[3] = 25
+        cache[4] = 30
+        cache[5] = 35
+
+        self.assertEqual(5, len(cache))
+        # This will bump us over the max, which causes us to shrink down to
+        # after_cleanup_cache size
+        cache[6] = 40
+        self.assertEqual(3, len(cache))
+
+    def test_after_cleanup_larger_than_max(self):
+        cache = lru_cache.LRUCache(max_cache=5, after_cleanup_count=10)
+        self.assertEqual(5, cache._after_cleanup_count)
+
+    def test_after_cleanup_none(self):
+        cache = lru_cache.LRUCache(max_cache=5, after_cleanup_count=None)
+        # By default _after_cleanup_size is 80% of the normal size
+        self.assertEqual(4, cache._after_cleanup_count)
+
+    def test_cleanup(self):
+        cache = lru_cache.LRUCache(max_cache=5, after_cleanup_count=2)
+
+        # Add these in order
+        cache[1] = 10
+        cache[2] = 20
+        cache[3] = 25
+        cache[4] = 30
+        cache[5] = 35
+
+        self.assertEqual(5, len(cache))
+        # Force a compaction
+        cache.cleanup()
+        self.assertEqual(2, len(cache))
+
+    def test_preserve_last_access_order(self):
+        cache = lru_cache.LRUCache(max_cache=5)
+
+        # Add these in order
+        cache[1] = 10
+        cache[2] = 20
+        cache[3] = 25
+        cache[4] = 30
+        cache[5] = 35
+
+        self.assertEqual([5, 4, 3, 2, 1], [n.key for n in walk_lru(cache)])
+
+        # Now access some randomly
+        cache[2]
+        cache[5]
+        cache[3]
+        cache[2]
+        self.assertEqual([2, 3, 5, 4, 1], [n.key for n in walk_lru(cache)])
+
+    def test_get(self):
+        cache = lru_cache.LRUCache(max_cache=5)
+
+        cache[1] = 10
+        cache[2] = 20
+        self.assertEqual(20, cache.get(2))
+        self.assertIs(None, cache.get(3))
+        obj = object()
+        self.assertIs(obj, cache.get(3, obj))
+        self.assertEqual([2, 1], [n.key for n in walk_lru(cache)])
+        self.assertEqual(10, cache.get(1))
+        self.assertEqual([1, 2], [n.key for n in walk_lru(cache)])
+
+    def test_keys(self):
+        cache = lru_cache.LRUCache(max_cache=5, after_cleanup_count=5)
+
+        cache[1] = 2
+        cache[2] = 3
+        cache[3] = 4
+        self.assertEqual([1, 2, 3], sorted(cache.keys()))
+        cache[4] = 5
+        cache[5] = 6
+        cache[6] = 7
+        self.assertEqual([2, 3, 4, 5, 6], sorted(cache.keys()))
+
+    def test_resize_smaller(self):
+        cache = lru_cache.LRUCache(max_cache=5, after_cleanup_count=4)
+        cache[1] = 2
+        cache[2] = 3
+        cache[3] = 4
+        cache[4] = 5
+        cache[5] = 6
+        self.assertEqual([1, 2, 3, 4, 5], sorted(cache.keys()))
+        cache[6] = 7
+        self.assertEqual([3, 4, 5, 6], sorted(cache.keys()))
+        # Now resize to something smaller, which triggers a cleanup
+        cache.resize(max_cache=3, after_cleanup_count=2)
+        self.assertEqual([5, 6], sorted(cache.keys()))
+        # Adding something will use the new size
+        cache[7] = 8
+        self.assertEqual([5, 6, 7], sorted(cache.keys()))
+        cache[8] = 9
+        self.assertEqual([7, 8], sorted(cache.keys()))
+
+    def test_resize_larger(self):
+        cache = lru_cache.LRUCache(max_cache=5, after_cleanup_count=4)
+        cache[1] = 2
+        cache[2] = 3
+        cache[3] = 4
+        cache[4] = 5
+        cache[5] = 6
+        self.assertEqual([1, 2, 3, 4, 5], sorted(cache.keys()))
+        cache[6] = 7
+        self.assertEqual([3, 4, 5, 6], sorted(cache.keys()))
+        cache.resize(max_cache=8, after_cleanup_count=6)
+        self.assertEqual([3, 4, 5, 6], sorted(cache.keys()))
+        cache[7] = 8
+        cache[8] = 9
+        cache[9] = 10
+        cache[10] = 11
+        self.assertEqual([3, 4, 5, 6, 7, 8, 9, 10], sorted(cache.keys()))
+        cache[11] = 12 # triggers cleanup back to new after_cleanup_count
+        self.assertEqual([6, 7, 8, 9, 10, 11], sorted(cache.keys()))
+
+
+class TestLRUSizeCache(tests.TestCase):
+
+    def test_basic_init(self):
+        cache = lru_cache.LRUSizeCache()
+        self.assertEqual(2048, cache._max_cache)
+        self.assertEqual(int(cache._max_size*0.8), cache._after_cleanup_size)
+        self.assertEqual(0, cache._value_size)
+
+    def test_add__null_key(self):
+        cache = lru_cache.LRUSizeCache()
+        self.assertRaises(ValueError,
+            cache.__setitem__, lru_cache._null_key, 1)
+
+    def test_add_tracks_size(self):
+        cache = lru_cache.LRUSizeCache()
+        self.assertEqual(0, cache._value_size)
+        cache['my key'] = 'my value text'
+        self.assertEqual(13, cache._value_size)
+
+    def test_remove_tracks_size(self):
+        cache = lru_cache.LRUSizeCache()
+        self.assertEqual(0, cache._value_size)
+        cache['my key'] = 'my value text'
+        self.assertEqual(13, cache._value_size)
+        node = cache._cache['my key']
+        cache._remove_node(node)
+        self.assertEqual(0, cache._value_size)
+
+    def test_no_add_over_size(self):
+        """Adding a large value may not be cached at all."""
+        cache = lru_cache.LRUSizeCache(max_size=10, after_cleanup_size=5)
+        self.assertEqual(0, cache._value_size)
+        self.assertEqual({}, cache.as_dict())
+        cache['test'] = 'key'
+        self.assertEqual(3, cache._value_size)
+        self.assertEqual({'test': 'key'}, cache.as_dict())
+        cache['test2'] = 'key that is too big'
+        self.assertEqual(3, cache._value_size)
+        self.assertEqual({'test':'key'}, cache.as_dict())
+        # If we would add a key, only to cleanup and remove all cached entries,
+        # then obviously that value should not be stored
+        cache['test3'] = 'bigkey'
+        self.assertEqual(3, cache._value_size)
+        self.assertEqual({'test':'key'}, cache.as_dict())
+
+        cache['test4'] = 'bikey'
+        self.assertEqual(3, cache._value_size)
+        self.assertEqual({'test':'key'}, cache.as_dict())
+
+    def test_adding_clears_cache_based_on_size(self):
+        """The cache is cleared in LRU order until small enough"""
+        cache = lru_cache.LRUSizeCache(max_size=20)
+        cache['key1'] = 'value' # 5 chars
+        cache['key2'] = 'value2' # 6 chars
+        cache['key3'] = 'value23' # 7 chars
+        self.assertEqual(5+6+7, cache._value_size)
+        cache['key2'] # reference key2 so it gets a newer reference time
+        cache['key4'] = 'value234' # 8 chars, over limit
+        # We have to remove 2 keys to get back under limit
+        self.assertEqual(6+8, cache._value_size)
+        self.assertEqual({'key2':'value2', 'key4':'value234'},
+                         cache.as_dict())
+
+    def test_adding_clears_to_after_cleanup_size(self):
+        cache = lru_cache.LRUSizeCache(max_size=20, after_cleanup_size=10)
+        cache['key1'] = 'value' # 5 chars
+        cache['key2'] = 'value2' # 6 chars
+        cache['key3'] = 'value23' # 7 chars
+        self.assertEqual(5+6+7, cache._value_size)
+        cache['key2'] # reference key2 so it gets a newer reference time
+        cache['key4'] = 'value234' # 8 chars, over limit
+        # We have to remove 3 keys to get back under limit
+        self.assertEqual(8, cache._value_size)
+        self.assertEqual({'key4':'value234'}, cache.as_dict())
+
+    def test_custom_sizes(self):
+        def size_of_list(lst):
+            return sum(len(x) for x in lst)
+        cache = lru_cache.LRUSizeCache(max_size=20, after_cleanup_size=10,
+                                       compute_size=size_of_list)
+
+        cache['key1'] = ['val', 'ue'] # 5 chars
+        cache['key2'] = ['val', 'ue2'] # 6 chars
+        cache['key3'] = ['val', 'ue23'] # 7 chars
+        self.assertEqual(5+6+7, cache._value_size)
+        cache['key2'] # reference key2 so it gets a newer reference time
+        cache['key4'] = ['value', '234'] # 8 chars, over limit
+        # We have to remove 3 keys to get back under limit
+        self.assertEqual(8, cache._value_size)
+        self.assertEqual({'key4':['value', '234']}, cache.as_dict())
+
+    def test_cleanup(self):
+        cache = lru_cache.LRUSizeCache(max_size=20, after_cleanup_size=10)
+
+        # Add these in order
+        cache['key1'] = 'value' # 5 chars
+        cache['key2'] = 'value2' # 6 chars
+        cache['key3'] = 'value23' # 7 chars
+        self.assertEqual(5+6+7, cache._value_size)
+
+        cache.cleanup()
+        # Only the most recent fits after cleaning up
+        self.assertEqual(7, cache._value_size)
+
+    def test_keys(self):
+        cache = lru_cache.LRUSizeCache(max_size=10)
+
+        cache[1] = 'a'
+        cache[2] = 'b'
+        cache[3] = 'cdef'
+        self.assertEqual([1, 2, 3], sorted(cache.keys()))
+
+    def test_resize_smaller(self):
+        cache = lru_cache.LRUSizeCache(max_size=10, after_cleanup_size=9)
+        cache[1] = 'abc'
+        cache[2] = 'def'
+        cache[3] = 'ghi'
+        cache[4] = 'jkl'
+        # Triggers a cleanup
+        self.assertEqual([2, 3, 4], sorted(cache.keys()))
+        # Resize should also cleanup again
+        cache.resize(max_size=6, after_cleanup_size=4)
+        self.assertEqual([4], sorted(cache.keys()))
+        # Adding should use the new max size
+        cache[5] = 'mno'
+        self.assertEqual([4, 5], sorted(cache.keys()))
+        cache[6] = 'pqr'
+        self.assertEqual([6], sorted(cache.keys()))
+
+    def test_resize_larger(self):
+        cache = lru_cache.LRUSizeCache(max_size=10, after_cleanup_size=9)
+        cache[1] = 'abc'
+        cache[2] = 'def'
+        cache[3] = 'ghi'
+        cache[4] = 'jkl'
+        # Triggers a cleanup
+        self.assertEqual([2, 3, 4], sorted(cache.keys()))
+        cache.resize(max_size=15, after_cleanup_size=12)
+        self.assertEqual([2, 3, 4], sorted(cache.keys()))
+        cache[5] = 'mno'
+        cache[6] = 'pqr'
+        self.assertEqual([2, 3, 4, 5, 6], sorted(cache.keys()))
+        cache[7] = 'stu'
+        self.assertEqual([4, 5, 6, 7], sorted(cache.keys()))
+