Cache getter instance

aiomisc/thread_pool.py

@@ -15,8 +15,9 @@
 from types import MappingProxyType
 from typing import (
     Any, Awaitable, Callable, Coroutine, Dict, FrozenSet, Generator, Generic,
-    Optional, Set, Tuple, TypeVar, Union, overload,
+    Optional, Set, Tuple, TypeVar, Union, overload, MutableMapping,
 )
+from weakref import WeakKeyDictionary
 
 from ._context_vars import EVENT_LOOP
 from .compat import Concatenate, ParamSpec
@@ -379,6 +380,8 @@ class Threaded(ThreadedBase[P, T]):
     func_type: type
 
     def __init__(self, func: Callable[P, T]) -> None:
+        self.__cache: MutableMapping[Any, Any] = WeakKeyDictionary()
+
         if isinstance(func, staticmethod):
             self.func_type = staticmethod
             self.func = func.__func__
@@ -415,14 +418,22 @@ def __get__(
         instance: Any,
         owner: Optional[type] = None,
     ) -> "Threaded[P, T] | BoundThreaded[Any, T]":
+        key = instance
+        result: Any
+        if key in self.__cache:
+            return self.__cache[key]
         if self.func_type is staticmethod:
-            return self
+            result = self
         elif self.func_type is classmethod:
             cls = owner if instance is None else type(instance)
-            return BoundThreaded(self.func, cls)
+            result = BoundThreaded(self.func, cls)
         elif instance is not None:
-            return BoundThreaded(self.func, instance)
-        return self
+            result = BoundThreaded(self.func, instance)
+        else:
+            result = self
+
+        self.__cache[key] = result
+        return result
 
 
 class BoundThreaded(ThreadedBase[P, T]):
@@ -570,6 +581,7 @@ def __init__(
 
         self.func = actual_func
         self.max_size = max_size
+        self.__cache: MutableMapping[Any, Any] = WeakKeyDictionary()
 
     @overload
     def __get__(
@@ -592,14 +604,23 @@ def __get__(
         instance: Any,
         owner: Optional[type] = None,
     ) -> "ThreadedIterable[P, T] | BoundThreadedIterable[Any, T]":
+        key = instance
+        result: Any
+        if key in self.__cache:
+            return self.__cache[key]
+
         if self.func_type is staticmethod:
-            return self
+            result = self
         elif self.func_type is classmethod:
             cls = owner if instance is None else type(instance)
-            return BoundThreadedIterable(self.func, cls, self.max_size)
+            result = BoundThreadedIterable(self.func, cls, self.max_size)
         elif instance is not None:
-            return BoundThreadedIterable(self.func, instance, self.max_size)
-        return self
+            result = BoundThreadedIterable(self.func, instance, self.max_size)
+        else:
+            result = self
+
+        self.__cache[key] = result
+        return result
 
 
 class BoundThreadedIterable(ThreadedIterableBase[P, T]):

tests/test_thread_pool.py

@@ -584,6 +584,7 @@ def foo(self):
             return 42
 
     instance = TestClass()
+    assert instance.foo is instance.foo
     assert instance.foo.sync_call() == 42
     assert await instance.foo() == 42
     assert await instance.foo.async_call() == 42
@@ -597,6 +598,7 @@ def foo():
             return 42
 
     instance = TestClass()
+    assert instance.foo is instance.foo
     assert instance.foo.sync_call() == 42
     assert await instance.foo() == 42
     assert await instance.foo.async_call() == 42
@@ -610,6 +612,7 @@ def foo(cls):
             return 42
 
     instance = TestClass()
+    assert instance.foo is instance.foo
     assert instance.foo.sync_call() == 42
     assert await instance.foo() == 42
     assert await instance.foo.async_call() == 42
@@ -620,6 +623,7 @@ async def test_threaded_iterator_class_func():
     def foo():
         yield 42
 
+    assert foo is foo
     assert list(foo.sync_call()) == [42]
     assert [x async for x in foo()] == [42]
     assert [x async for x in foo.async_call()] == [42]
@@ -632,6 +636,7 @@ def foo(self):
             yield 42
 
     instance = TestClass()
+    assert instance.foo is instance.foo
     assert list(instance.foo.sync_call()) == [42]
     assert [x async for x in instance.foo()] == [42]
     assert [x async for x in instance.foo.async_call()] == [42]
@@ -645,6 +650,7 @@ def foo():
             yield 42
 
     instance = TestClass()
+    assert instance.foo is instance.foo
     assert list(instance.foo.sync_call()) == [42]
     assert [x async for x in instance.foo()] == [42]
     assert [x async for x in instance.foo.async_call()] == [42]
@@ -658,6 +664,7 @@ def foo(cls):
             yield 42
 
     instance = TestClass()
+    assert instance.foo is instance.foo
     assert list(instance.foo.sync_call()) == [42]
     assert [x async for x in instance.foo()] == [42]
     assert [x async for x in instance.foo.async_call()] == [42]