From 45ed845701d36bea640b97524a409806da97151a Mon Sep 17 00:00:00 2001
From: Ivan Levkivskyi <levkivskyi@gmail.com>
Date: Sun, 8 Mar 2026 14:08:21 +0000
Subject: [PATCH] Handle hex bigint literals in nativeparse

---
 mypy/nativeparse.py               | 2 +-
 test-data/unit/native-parser.test | 5 +++--
 2 files changed, 4 insertions(+), 3 deletions(-)

diff --git a/mypy/nativeparse.py b/mypy/nativeparse.py
index 4f7f0636b3cd..5a6566c8a266 100644
--- a/mypy/nativeparse.py
+++ b/mypy/nativeparse.py
@@ -1582,7 +1582,7 @@ def read_expression(state: State, data: ReadBuffer) -> Expression:
         return expr
     elif tag == nodes.BIG_INT_EXPR:
         strval = read_str(data)
-        ie = IntExpr(int(strval))
+        ie = IntExpr(int(strval, base=0))
         read_loc(data, ie)
         expect_end_tag(data)
         return ie
diff --git a/test-data/unit/native-parser.test b/test-data/unit/native-parser.test
index 8d7d53485e84..f2cdc74b444c 100644
--- a/test-data/unit/native-parser.test
+++ b/test-data/unit/native-parser.test
@@ -40,7 +40,7 @@ MypyFile:1(
       StrExpr(z))))
 
 [case testIntExpr]
-(0, 1, 2, 203, 5345, 50123, 1234567890, 9982374892739487239847897928374897298374)
+(0, 1, 2, 203, 5345, 50123, 1234567890, 9982374892739487239847897928374897298374, 0x1950A86A20F9469CFC6C)
 [out]
 MypyFile:1(
   ExpressionStmt:1(
@@ -52,7 +52,8 @@ MypyFile:1(
       IntExpr(5345)
       IntExpr(50123)
       IntExpr(1234567890)
-      IntExpr(9982374892739487239847897928374897298374))))
+      IntExpr(9982374892739487239847897928374897298374)
+      IntExpr(119547037146038801333356))))
 
 [case testAssignmentStmt]
 x = 1