Fixed #36810 -- Avoided infinite recursion in SimpleLazyObject.__repr__().

Detect when `SimpleLazyObject._setupfunc` is a bound method of the same
instance to use a safe representation and avoid infinite recursion.

django/utils/functional.py

@@ -407,7 +407,11 @@ class SimpleLazyObject(LazyObject):
     # without evaluating the wrapped object.
     def __repr__(self):
         if self._wrapped is empty:
-            repr_attr = self._setupfunc
+            # Avoid recursion if setupfunc is a bound method of this instance.
+            if getattr(self._setupfunc, "__self__", None) is self:
+                repr_attr = f"<bound method {self._setupfunc.__name__}>"
+            else:
+                repr_attr = self._setupfunc
         else:
             repr_attr = self._wrapped
         return "<%s: %r>" % (type(self).__name__, repr_attr)

tests/utils_tests/test_lazyobject.py

@@ -348,6 +348,22 @@ class SimpleLazyObjectTestCase(LazyObjectTestCase):
         self.assertIsInstance(obj._wrapped, int)
         self.assertEqual(repr(obj), "<SimpleLazyObject: 42>")
 
+    def test_repr_bound_method(self):
+
+        class MyLazyGenerator(SimpleLazyObject):
+            def __init__(self):
+                super().__init__(self._generate)
+
+            def _generate(self):
+                return "test-generated-value"
+
+        obj = MyLazyGenerator()
+        self.assertEqual(repr(obj), "<MyLazyGenerator: '<bound method _generate>'>")
+        self.assertIs(obj._wrapped, empty)  # The evaluation hasn't happened.
+
+        self.assertEqual(str(obj), "test-generated-value")  # Evaluate.
+        self.assertEqual(repr(obj), "<MyLazyGenerator: 'test-generated-value'>")
+
     def test_add(self):
         obj1 = self.lazy_wrap(1)
         self.assertEqual(obj1 + 1, 2)