From e47e3b8a2283559d6918a3c02689f6b821562b6b Mon Sep 17 00:00:00 2001
From: Synrom <max.leiwig@gmail.com>
Date: Thu, 28 Aug 2025 09:33:52 +0000
Subject: [PATCH 1/3] [fix] Fix parsing deeply nested parentheses causing
 MemoryError

---
 ChangeLog              |  4 ++++
 astroid/builder.py     |  2 +-
 tests/test_regrtest.py | 11 ++++++++++-
 3 files changed, 15 insertions(+), 2 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index 47bb4d19b..08d1f67d3 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -7,6 +7,10 @@ What's New in astroid 4.0.0?
 ============================
 Release date: TBA
 
+* Fix parsing deeply nested parentheses causing MemoryError
+
+  Closes #2643
+
 * Fix crash when inferring namedtuple with invalid field name looking like f-string formatting.
 
   Closes #2519
diff --git a/astroid/builder.py b/astroid/builder.py
index 6205f83d4..a107fed99 100644
--- a/astroid/builder.py
+++ b/astroid/builder.py
@@ -181,7 +181,7 @@ def _data_build(
             node, parser_module = _parse_string(
                 data, type_comments=True, modname=modname
             )
-        except (TypeError, ValueError, SyntaxError) as exc:
+        except (TypeError, ValueError, SyntaxError, MemoryError) as exc:
             raise AstroidSyntaxError(
                 "Parsing Python code failed:\n{error}",
                 source=data,
diff --git a/tests/test_regrtest.py b/tests/test_regrtest.py
index 1b16662c6..0294cdeea 100644
--- a/tests/test_regrtest.py
+++ b/tests/test_regrtest.py
@@ -13,7 +13,7 @@
 from astroid.builder import AstroidBuilder, _extract_single_node, extract_node
 from astroid.const import PY312_PLUS
 from astroid.context import InferenceContext
-from astroid.exceptions import InferenceError
+from astroid.exceptions import AstroidSyntaxError, InferenceError
 from astroid.manager import AstroidManager
 from astroid.raw_building import build_module
 from astroid.util import Uninferable
@@ -561,3 +561,12 @@ def test_regression_infer_namedtuple_invalid_fieldname_error() -> None:
     node = extract_node(code)
     inferred = next(node.infer())
     assert inferred.value == Uninferable
+
+
+def test_regression_parse_deeply_nested_parentheses() -> None:
+    """Regression test for issue #2643."""
+    with pytest.raises(AstroidSyntaxError, match="Parsing Python code failed:") as ctx:
+        extract_node(
+            "A=((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((c,j=t"
+        )
+    assert isinstance(ctx.value.error, MemoryError)

From c93f6a704db57654fe820041d59f85a9fa496e86 Mon Sep 17 00:00:00 2001
From: Synrom <max.leiwig@gmail.com>
Date: Thu, 28 Aug 2025 10:03:50 +0000
Subject: [PATCH 2/3] tests: fix regression test for deeply nested parentheses
 on PyPy3.10

---
 tests/test_regrtest.py | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/tests/test_regrtest.py b/tests/test_regrtest.py
index 0294cdeea..0ff3b6f52 100644
--- a/tests/test_regrtest.py
+++ b/tests/test_regrtest.py
@@ -2,6 +2,7 @@
 # For details: https://github.com/pylint-dev/astroid/blob/main/LICENSE
 # Copyright (c) https://github.com/pylint-dev/astroid/blob/main/CONTRIBUTORS.txt
 
+import platform
 import sys
 import textwrap
 import unittest
@@ -569,4 +570,7 @@ def test_regression_parse_deeply_nested_parentheses() -> None:
         extract_node(
             "A=((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((c,j=t"
         )
-    assert isinstance(ctx.value.error, MemoryError)
+    expected = (
+        SyntaxError if platform.python_implementation() == "PyPy" else MemoryError
+    )
+    assert isinstance(ctx.value.error, expected)

From cf2227a8dd6d4aae2d7bb05ab07611c80a5b9de2 Mon Sep 17 00:00:00 2001
From: Synrom <max.leiwig@gmail.com>
Date: Thu, 28 Aug 2025 11:42:29 +0000
Subject: [PATCH 3/3] Update ChangeLog

---
 ChangeLog | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/ChangeLog b/ChangeLog
index 08d1f67d3..379a2a748 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -7,7 +7,7 @@ What's New in astroid 4.0.0?
 ============================
 Release date: TBA
 
-* Fix parsing deeply nested parentheses causing MemoryError
+* Prevent crash when parsing deeply nested parentheses causing MemoryError in python's built-in ast.
 
   Closes #2643