Add attr.Factory to the recognized class attributes for classes d…

…ecorated with ``attrs``.

Closes pylint-dev/pylint#4341

ChangeLog

@@ -64,6 +64,10 @@ Release date: TBA
 
   Closes pylint-dev/pylint#8544
 
+* Add ``attr.Factory`` to the recognized class attributes for classes decorated with ``attrs``.
+
+  Closes pylint-dev/pylint#4341
+
 * ``infer_property()`` now observes the same property-specific workaround as ``infer_functiondef``.
 
   Refs #1490

astroid/brain/brain_attrs.py

@@ -14,7 +14,15 @@
 from astroid.nodes.scoped_nodes import ClassDef
 
 ATTRIB_NAMES = frozenset(
-    ("attr.ib", "attrib", "attr.attrib", "attr.field", "attrs.field", "field")
+    (
+        "attr.Factory",
+        "attr.ib",
+        "attrib",
+        "attr.attrib",
+        "attr.field",
+        "attrs.field",
+        "field",
+    )
 )
 ATTRS_NAMES = frozenset(
     (

tests/brain/test_attr.py

@@ -74,10 +74,16 @@ class Eggs:
 
         l = Eggs(d=1)
         l.d['answer'] = 42
+
+        @attr.attrs(auto_attribs=True)
+        class Eggs:
+            d: int = attr.Factory(lambda: 3)
+
+        m = Eggs(d=1)
         """
         )
 
-        for name in ("f", "g", "h", "i", "j", "k", "l"):
+        for name in ("f", "g", "h", "i", "j", "k", "l", "m"):
             should_be_unknown = next(module.getattr(name)[0].infer()).getattr("d")[0]
             self.assertIsInstance(should_be_unknown, astroid.Unknown)