feat: new mypyc primitives for weakref.proxy

mypyc/primitives/weakref_ops.py

@@ -20,3 +20,21 @@
     c_function_name="PyWeakref_NewRef",
     error_kind=ERR_MAGIC,
 )
+
+new_proxy_op = function_op(
+    name="_weakref.proxy",
+    arg_types=[object_rprimitive],
+    return_type=object_rprimitive,
+    c_function_name="PyWeakref_NewProxy",
+    extra_int_constants=[(0, pointer_rprimitive)],
+    error_kind=ERR_MAGIC,
+)
+
+new_proxy_with_callback_op = function_op(
+    name="_weakref.proxy",
+    arg_types=[object_rprimitive, object_rprimitive],
+    # steals=[True, False],
+    return_type=object_rprimitive,
+    c_function_name="PyWeakref_NewProxy",
+    error_kind=ERR_MAGIC,
+)

mypyc/test-data/fixtures/test-weakref.pyi

@@ -0,0 +1,10 @@
+class dict: ...
+class ellipsis: ...
+class int: ...
+class str: ...
+class tuple: ...
+class type: ...
+class list: ...
+class BaseException: ...
+class Exception(BaseException): ...
+class ReferenceError(Exception): ...

mypyc/test-data/irbuild-weakref.test

@@ -49,3 +49,55 @@ def f(x, cb):
 L0:
     r0 = PyWeakref_NewRef(x, cb)
     return r0
+
+[case testWeakrefProxy]
+import weakref
+from typing import Any, Callable
+def f(x: object) -> object:
+    return weakref.proxy(x)
+
+[out]
+def f(x):
+    x, r0 :: object
+L0:
+    r0 = PyWeakref_NewProxy(x, 0)
+    return r0
+
+[case testWeakrefProxyCallback]
+import weakref
+from typing import Any, Callable
+def f(x: object, cb: Callable[[object], Any]) -> object:
+    return weakref.proxy(x, cb)
+
+[out]
+def f(x, cb):
+    x, cb, r0 :: object
+L0:
+    r0 = PyWeakref_NewProxy(x, cb)
+    return r0
+
+[case testFromWeakrefProxy]
+from typing import Any, Callable
+from weakref import proxy
+def f(x: object) -> object:
+    return proxy(x)
+
+[out]
+def f(x):
+    x, r0 :: object
+L0:
+    r0 = PyWeakref_NewProxy(x, 0)
+    return r0
+
+[case testFromWeakrefProxyCallback]
+from typing import Any, Callable
+from weakref import proxy
+def f(x: object, cb: Callable[[object], Any]) -> object:
+    return proxy(x, cb)
+
+[out]
+def f(x, cb):
+    x, cb, r0 :: object
+L0:
+    r0 = PyWeakref_NewProxy(x, cb)
+    return r0

mypyc/test-data/run-weakref.test

@@ -7,7 +7,6 @@ from mypy_extensions import mypyc_attr
 @mypyc_attr(native_class=False)
 class Object:
     """some random weakreffable object"""
-    pass
 
 def test_weakref_ref():
     obj = Object()
@@ -16,6 +15,20 @@ def test_weakref_ref():
     obj = None
     assert r() is None, r()
 
+[file driver.py]
+from native import test_weakref_ref
+
+test_weakref_ref()
+
+
+[case testWeakrefRefWithCallback]
+from weakref import ref
+from mypy_extensions import mypyc_attr
+
+@mypyc_attr(native_class=False)
+class Object:
+    """some random weakreffable object"""
+
 def test_weakref_ref_with_callback():
     obj = Object()
     r = ref(obj, lambda x: x)
@@ -24,7 +37,62 @@ def test_weakref_ref_with_callback():
     assert r() is None, r()
 
 [file driver.py]
-from native import test_weakref_ref, test_weakref_ref_with_callback
+from native import test_weakref_ref_with_callback
 
-test_weakref_ref()
 test_weakref_ref_with_callback()
+
+
+[case testWeakrefProxy]
+import pytest  # type: ignore [import-not-found]
+from weakref import proxy
+from mypy_extensions import mypyc_attr
+
+@mypyc_attr(native_class=False)
+class Object:
+    """some random weakreffable object"""
+    def some_meth(self) -> int:
+        return 1
+
+def test_weakref_proxy():
+    obj = Object()
+    p = proxy(obj)
+    assert obj.some_meth() == 1
+    assert p.some_meth() == 1
+    obj.some_meth()
+    obj = None
+    with pytest.raises(ReferenceError):
+        p.some_meth()
+
+[builtins fixtures/test-weakref.pyi]
+[file driver.py]
+from native import test_weakref_proxy
+
+test_weakref_proxy()
+
+
+[case testWeakrefProxyWithCallback]
+import pytest  # type: ignore [import-not-found]
+from weakref import proxy
+from mypy_extensions import mypyc_attr
+
+@mypyc_attr(native_class=False)
+class Object:
+    """some random weakreffable object"""
+    def some_meth(self) -> int:
+        return 1
+
+def test_weakref_proxy_with_callback():
+    obj = Object()
+    p = proxy(obj, lambda x: x)
+    assert obj.some_meth() == 1
+    assert p.some_meth() == 1
+    obj.some_meth()
+    obj = None
+    with pytest.raises(ReferenceError):
+        p.some_meth()
+
+[builtins fixtures/test-weakref.pyi]
+[file driver.py]
+from native import test_weakref_proxy_with_callback
+
+test_weakref_proxy_with_callback()

test-data/unit/lib-stub/_weakref.pyi

@@ -0,0 +1,11 @@
+from typing import Any, Callable, TypeVar, overload
+from weakref import CallableProxyType
+
+_C = TypeVar("_C", bound=Callable[..., Any])
+_T = TypeVar("_T")
+
+# Return CallableProxyType if object is callable, ProxyType otherwise
+@overload
+def proxy(object: _C, callback: Callable[[_C], Any] | None = None, /) -> CallableProxyType[_C]: ...
+@overload
+def proxy(object: _T, callback: Callable[[_T], Any] | None = None, /) -> Any: ...

test-data/unit/lib-stub/weakref.pyi

@@ -1,11 +1,22 @@
+from _weakref import proxy
 from collections.abc import Callable
-from typing import Any, Generic, TypeVar
+from typing import Any, ClassVar, Generic, TypeVar, final
 from typing_extensions import Self
 
+_C = TypeVar("_C", bound=Callable[..., Any])
 _T = TypeVar("_T")
 
 class ReferenceType(Generic[_T]):  # "weakref"
     __callback__: Callable[[Self], Any]
     def __new__(cls, o: _T, callback: Callable[[Self], Any] | None = ..., /) -> Self: ...
 
 ref = ReferenceType
+
+@final
+class CallableProxyType(Generic[_C]):  # "weakcallableproxy"
+    def __eq__(self, value: object, /) -> bool: ...
+    def __getattr__(self, attr: str) -> Any: ...
+    __call__: _C
+    __hash__: ClassVar[None]  # type: ignore[assignment]
+
+__all__ = ["proxy"]