From 7cad63a514da31e733545401b411a1dd656a8240 Mon Sep 17 00:00:00 2001
From: "github-actions[bot]"
 <41898282+github-actions[bot]@users.noreply.github.com>
Date: Tue, 12 Dec 2023 00:02:48 +0000
Subject: [PATCH] Avoid duplicate inference results for `Tuple[Optional[int],
 ...]` (#2340) (#2342)

(cherry picked from commit dc13d5b66cec53b26b3c04df07f14724588a09a6)

Co-authored-by: Jacob Walls <jacobtylerwalls@gmail.com>
---
 ChangeLog                     |  5 +++++
 astroid/brain/brain_typing.py |  4 ++++
 tests/brain/test_brain.py     | 10 ++++++++++
 3 files changed, 19 insertions(+)

diff --git a/ChangeLog b/ChangeLog
index 3e2eaacf2b..c45e6972b2 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -13,6 +13,11 @@ What's New in astroid 3.0.2?
 ============================
 Release date: TBA
 
+* Avoid duplicate inference results for some uses of ``typing.X`` constructs like
+  ``Tuple[Optional[int], ...]``. This was causing pylint to occasionally omit
+  messages like ``deprecated-typing-alias``.
+
+  Closes pylint-dev/pylint#9220
 
 
 What's New in astroid 3.0.1?
diff --git a/astroid/brain/brain_typing.py b/astroid/brain/brain_typing.py
index d4b2ca0a5a..ea49644083 100644
--- a/astroid/brain/brain_typing.py
+++ b/astroid/brain/brain_typing.py
@@ -188,6 +188,8 @@ def infer_typing_attr(
             cache = node.parent.__cache  # type: ignore[attr-defined] # Unrecognized getattr
             if cache.get(node.parent.slots) is not None:
                 del cache[node.parent.slots]
+        # Avoid re-instantiating this class every time it's seen
+        node._explicit_inference = lambda node, context: iter([value])
         return iter([value])
 
     node = extract_node(TYPING_TYPE_TEMPLATE.format(value.qname().split(".")[-1]))
@@ -393,6 +395,8 @@ def infer_special_alias(
     class_def.postinit(bases=[res], body=[], decorators=None)
     func_to_add = _extract_single_node(CLASS_GETITEM_TEMPLATE)
     class_def.locals["__class_getitem__"] = [func_to_add]
+    # Avoid re-instantiating this class every time it's seen
+    node._explicit_inference = lambda node, context: iter([class_def])
     return iter([class_def])
 
 
diff --git a/tests/brain/test_brain.py b/tests/brain/test_brain.py
index 12cdd5cf7d..aebf005889 100644
--- a/tests/brain/test_brain.py
+++ b/tests/brain/test_brain.py
@@ -668,6 +668,16 @@ def test_typing_no_duplicates(self):
         )
         assert len(node.inferred()) == 1
 
+    @test_utils.require_version(minver="3.9")
+    def test_typing_no_duplicates_2(self):
+        node = builder.extract_node(
+            """
+        from typing import Optional, Tuple
+        Tuple[Optional[int], ...]
+        """
+        )
+        assert len(node.inferred()) == 1
+
     def test_collections_generic_alias_slots(self):
         """Test slots for a class which is a subclass of a generic alias type."""
         node = builder.extract_node(