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| author | Raymond Hettinger <python@rcn.com> | 2010-08-14 23:52:08 (GMT) |
|---|---|---|
| committer | Raymond Hettinger <python@rcn.com> | 2010-08-14 23:52:08 (GMT) |
| commit | 0f56e90f0582a4171a9e3e1e2ffde2781be4bffd (patch) | |
| tree | 32bc9fd46a929f5ac2115b8591d54efad1ec9efa | |
| parent | a893927491ef3bc7a4c3c9aa548be7d8ff677c38 (diff) | |
| download | cpython-0f56e90f0582a4171a9e3e1e2ffde2781be4bffd.zip cpython-0f56e90f0582a4171a9e3e1e2ffde2781be4bffd.tar.gz cpython-0f56e90f0582a4171a9e3e1e2ffde2781be4bffd.tar.bz2 | |
Support cache sizes.
| -rw-r--r-- | Lib/functools.py | 2 | ||||
| -rw-r--r-- | Lib/test/test_functools.py | 48 |
2 files changed, 49 insertions, 1 deletions
diff --git a/Lib/functools.py b/Lib/functools.py index f6ae4f4..9f28004 100644 --- a/Lib/functools.py +++ b/Lib/functools.py @@ -144,7 +144,7 @@ def lfu_cache(maxsize=100): wrapper.misses += 1 if len(cache) > maxsize: # purge the 10% least frequently used entries - for key, _ in nsmallest(maxsize // 10, + for key, _ in nsmallest(maxsize // 10 or 1, use_count.items(), key=itemgetter(1)): del cache[key], use_count[key] diff --git a/Lib/test/test_functools.py b/Lib/test/test_functools.py index 70a8ad6..4dd6fab 100644 --- a/Lib/test/test_functools.py +++ b/Lib/test/test_functools.py @@ -482,6 +482,30 @@ class TestLRU(unittest.TestCase): self.assertEqual(f.hits, 0) self.assertEqual(f.misses, 1) + # test size zero (which means "never-cache") + f_cnt = 0 + @functools.lru_cache(0) + def f(): + nonlocal f_cnt + f_cnt += 1 + return 20 + self.assertEqual(f(), 20) + self.assertEqual(f(), 20) + self.assertEqual(f(), 20) + self.assertEqual(f_cnt, 3) + + # test size one + f_cnt = 0 + @functools.lru_cache(1) + def f(): + nonlocal f_cnt + f_cnt += 1 + return 20 + self.assertEqual(f(), 20) + self.assertEqual(f(), 20) + self.assertEqual(f(), 20) + self.assertEqual(f_cnt, 1) + def test_lfu(self): def orig(x, y): return 3*x+y @@ -503,6 +527,30 @@ class TestLRU(unittest.TestCase): self.assertEqual(f.hits, 0) self.assertEqual(f.misses, 1) + # test size zero (which means "never-cache") + f_cnt = 0 + @functools.lfu_cache(0) + def f(): + nonlocal f_cnt + f_cnt += 1 + return 20 + self.assertEqual(f(), 20) + self.assertEqual(f(), 20) + self.assertEqual(f(), 20) + self.assertEqual(f_cnt, 3) + + # test size one + f_cnt = 0 + @functools.lfu_cache(1) + def f(): + nonlocal f_cnt + f_cnt += 1 + return 20 + self.assertEqual(f(), 20) + self.assertEqual(f(), 20) + self.assertEqual(f(), 20) + self.assertEqual(f_cnt, 1) + def test_main(verbose=None): test_classes = ( TestPartial, |