Support cached properties

src/classify/classification.py

@@ -16,6 +16,7 @@
 )
 from .filters import (
     is_attribute,
+    is_cached_property,
     is_data_descriptor,
     is_inner_class,
     is_method,
@@ -67,6 +68,13 @@ def classify[C](obj: type[C]) -> Class:
             prop = Method.from_func(member.obj.fget, member.cls)
             properties[member.name].append(prop)
 
+        ## CACHED PROPERTIES
+        cached_props = [m for m in members if is_cached_property(m)]
+        for member in cached_props:
+            logger.debug("extracting cached property", member=member)
+            prop = Method.from_func(member.obj, member.cls)
+            properties[member.name].append(prop)
+
         ## DATA DESCRIPTORS
         descriptors = [m for m in members if is_data_descriptor(m)]
         for member in descriptors:

src/classify/filters.py

@@ -5,7 +5,28 @@
 
 
 def is_attribute(member: Member) -> bool:
-    return member.kind == "data" and not is_inner_class(member)
+    return (
+        member.kind == "data"
+        and not is_inner_class(member)
+        and not is_cached_property(member)
+    )
+
+
+def is_cached_property(member: Member) -> bool:
+    # covers functools.cached_property and variations like
+    # django.utils.functional.cached_property.
+    # These are method descriptors wrapping a function, so they get
+    # reported as "method", but the descriptor is not callable.
+    cls = type(member.obj)
+    # getattr_static: getattr() would call arbitrary __getattr__
+    # implementations on member values
+    func = inspect.getattr_static(member.obj, "func", None)
+    return (
+        hasattr(cls, "__get__")
+        and not hasattr(cls, "__set__")
+        and not callable(member.obj)
+        and callable(func)
+    )
 
 
 def is_data_descriptor(member: Member) -> bool:

tests/test_classification.py

@@ -32,6 +32,14 @@ def test_classify_includes_wrapped_methods(name):
     assert name in structure.methods
 
 
+@pytest.mark.parametrize("name", ["my_cached_prop", "my_dj_cached_prop"])
+def test_classify_cached_properties_are_properties(name):
+    structure = classify(DummyClass)
+
+    assert name in structure.properties
+    assert name not in structure.methods
+
+
 def test_classify_excludes_c_implemented_methods():
     class MyDict(dict):
         def mine(self): ...