commit 1f45cc0dfa9a8febfc256411c803b4536719db97
author Miss Islington (bot) <31488909+miss-islington@users.noreply.github.com> Thu Oct 28 01:09:41 2021 -0700
committer GitHub <noreply@github.com> Thu Oct 28 01:09:41 2021 -0700
tree 2049fe508942ef5439b1d5f0afd4e4f05c63c0be
parent ce7a6afb797d2ffde45e9e902516b8437c8f9e31

bpo-44904: Fix classmethod property bug in doctest module (GH-28838)


The doctest module raised an error if a docstring contained an example that
attempted to access a classmethod property. (Stacking '@classmethod' on top of
`@property` has been supported since Python 3.9; see
https://docs.python.org/3/howto/descriptor.htmlGH-class-methods.)

Co-authored-by: Serhiy Storchaka <storchaka@gmail.com>
(cherry picked from commit b1302abcc8a4be5f39b4d60a1ce28032b77655b3)

Co-authored-by: Alex Waygood <Alex.Waygood@Gmail.com>

Lib/doctest.py

diff --git a/Lib/doctest.py b/Lib/doctest.py
index ba898f6..b27cbdf 100644
--- a/Lib/doctest.py
+++ b/Lib/doctest.py
@@ -1034,10 +1034,8 @@ def _find(self, tests, obj, name, module, source_lines, globs, seen):
         if inspect.isclass(obj) and self._recurse:
             for valname, val in obj.__dict__.items():
                 # Special handling for staticmethod/classmethod.
-                if isinstance(val, staticmethod):
-                    val = getattr(obj, valname)
-                if isinstance(val, classmethod):
-                    val = getattr(obj, valname).__func__
+                if isinstance(val, (staticmethod, classmethod)):
+                    val = val.__func__
 
                 # Recurse to methods, properties, and nested classes.
                 if ((inspect.isroutine(val) or inspect.isclass(val) or

Lib/test/test_doctest.py

diff --git a/Lib/test/test_doctest.py b/Lib/test/test_doctest.py
index 7f8ccd3..9703f87 100644
--- a/Lib/test/test_doctest.py
+++ b/Lib/test/test_doctest.py
@@ -96,6 +96,17 @@ def a_classmethod(cls, v):
         22
         """)
 
+    a_class_attribute = 42
+
+    @classmethod
+    @property
+    def a_classmethod_property(cls):
+        """
+        >>> print(SampleClass.a_classmethod_property)
+        42
+        """
+        return cls.a_class_attribute
+
     class NestedClass:
         """
         >>> x = SampleClass.NestedClass(5)
@@ -501,6 +512,7 @@ def basics(): r"""
      1  SampleClass.NestedClass.__init__
      1  SampleClass.__init__
      2  SampleClass.a_classmethod
+     1  SampleClass.a_classmethod_property
      1  SampleClass.a_property
      1  SampleClass.a_staticmethod
      1  SampleClass.double
@@ -556,6 +568,7 @@ def basics(): r"""
      1  some_module.SampleClass.NestedClass.__init__
      1  some_module.SampleClass.__init__
      2  some_module.SampleClass.a_classmethod
+     1  some_module.SampleClass.a_classmethod_property
      1  some_module.SampleClass.a_property
      1  some_module.SampleClass.a_staticmethod
      1  some_module.SampleClass.double
@@ -597,6 +610,7 @@ def basics(): r"""
      1  SampleClass.NestedClass.__init__
      1  SampleClass.__init__
      2  SampleClass.a_classmethod
+     1  SampleClass.a_classmethod_property
      1  SampleClass.a_property
      1  SampleClass.a_staticmethod
      1  SampleClass.double
@@ -617,6 +631,7 @@ def basics(): r"""
      0  SampleClass.NestedClass.square
      1  SampleClass.__init__
      2  SampleClass.a_classmethod
+     1  SampleClass.a_classmethod_property
      1  SampleClass.a_property
      1  SampleClass.a_staticmethod
      1  SampleClass.double