[unused-private-member] Handle the case using self to access members

As seen in issue #4644

3 files changed, 22 insertions, 1 deletions

diff --git a/ChangeLog b/ChangeLog
index c84b2620b..ef043efa1 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -22,6 +22,11 @@ Release date: TBA
 
   Closes #4638
 
+* Fix a false positive for ``unused-private-member`` when accessing a private variable
+  with ``self``
+
+  Closes #4644
+
 
 What's New in Pylint 2.9.1?
 ===========================
diff --git a/pylint/checkers/classes.py b/pylint/checkers/classes.py
index 8f1eeec22..abf77a416 100644
--- a/pylint/checkers/classes.py
+++ b/pylint/checkers/classes.py
@@ -949,7 +949,7 @@ a metaclass class method.",
                 if (
                     isinstance(child, astroid.Attribute)
                     and child.attrname == assign_name.name
-                    and child.expr.name in ("cls", node.name)
+                    and child.expr.name in ("self", "cls", node.name)
                 ):
                     break
             else:
diff --git a/tests/functional/u/unused/unused_private_member.py b/tests/functional/u/unused/unused_private_member.py
index 9fb02cf92..a8312e107 100644
--- a/tests/functional/u/unused/unused_private_member.py
+++ b/tests/functional/u/unused/unused_private_member.py
@@ -87,3 +87,19 @@ class Bla:
     @classmethod
     def __c(cls):
         pass
+
+
+class Klass:
+    """Regression test for 4644"""
+
+    __seventyseven = 77
+    __ninetyone = 91
+
+    def __init__(self):
+        self.twentyone = 21 * (1 / (self.__seventyseven + 33)) % 100
+        self.ninetyfive = Klass.__ninetyone + 4
+
+
+k = Klass()
+print(k.twentyone)
+print(k.ninetyfive)