Add test for RLock in the lru_cache().
diff --git a/Lib/test/test_functools.py b/Lib/test/test_functools.py
index b3803da..db1e934 100644
--- a/Lib/test/test_functools.py
+++ b/Lib/test/test_functools.py
@@ -777,6 +777,31 @@
self.assertEqual(square.cache_info().hits, 4)
self.assertEqual(square.cache_info().misses, 4)
+ def test_need_for_rlock(self):
+ # This will deadlock on an LRU cache that uses a regular lock
+
+ @functools.lru_cache(maxsize=10)
+ def test_func(x):
+ 'Used to demonstrate a reentrant lru_cache call within a single thread'
+ return x
+
+ class DoubleEq:
+ 'Demonstrate a reentrant lru_cache call within a single thread'
+ def __init__(self, x):
+ self.x = x
+ def __hash__(self):
+ return self.x
+ def __eq__(self, other):
+ if self.x == 2:
+ test_func(DoubleEq(1))
+ return self.x == other.x
+
+ test_func(DoubleEq(1)) # Load the cache
+ test_func(DoubleEq(2)) # Load the cache
+ self.assertEqual(test_func(DoubleEq(2)), # Trigger a re-entrant __eq__ call
+ DoubleEq(2)) # Verify the correct return value
+
+
def test_main(verbose=None):
test_classes = (
TestPartial,