From 2d8713ebb3c71339b73e975435edf81d33b84320 Mon Sep 17 00:00:00 2001
From: Jeong YunWon <jeong@youknowone.org>
Date: Mon, 23 Jun 2025 01:02:51 +0900
Subject: [PATCH] Fix bz2 pickle

---
 Lib/test/test_bz2.py |  4 ----
 stdlib/src/bz2.rs    | 10 ++++++++++
 2 files changed, 10 insertions(+), 4 deletions(-)

diff --git a/Lib/test/test_bz2.py b/Lib/test/test_bz2.py
index b716d6016b..dfc444cbbd 100644
--- a/Lib/test/test_bz2.py
+++ b/Lib/test/test_bz2.py
@@ -676,8 +676,6 @@ def testCompress4G(self, size):
         finally:
             data = None
 
-    # TODO: RUSTPYTHON
-    @unittest.expectedFailure
     def testPickle(self):
         for proto in range(pickle.HIGHEST_PROTOCOL + 1):
             with self.assertRaises(TypeError):
@@ -736,8 +734,6 @@ def testDecompress4G(self, size):
             compressed = None
             decompressed = None
 
-    # TODO: RUSTPYTHON
-    @unittest.expectedFailure
     def testPickle(self):
         for proto in range(pickle.HIGHEST_PROTOCOL + 1):
             with self.assertRaises(TypeError):
diff --git a/stdlib/src/bz2.rs b/stdlib/src/bz2.rs
index 4ae0785e47..eb334ede7b 100644
--- a/stdlib/src/bz2.rs
+++ b/stdlib/src/bz2.rs
@@ -103,6 +103,11 @@ mod _bz2 {
             self.state.lock().needs_input()
         }
 
+        #[pymethod(name = "__reduce__")]
+        fn reduce(&self, vm: &VirtualMachine) -> PyResult<()> {
+            Err(vm.new_type_error("cannot pickle '_bz2.BZ2Decompressor' object".to_owned()))
+        }
+
         // TODO: mro()?
     }
 
@@ -185,5 +190,10 @@ mod _bz2 {
             state.flushed = true;
             Ok(vm.ctx.new_bytes(out.to_vec()))
         }
+
+        #[pymethod(name = "__reduce__")]
+        fn reduce(&self, vm: &VirtualMachine) -> PyResult<()> {
+            Err(vm.new_type_error("cannot pickle '_bz2.BZ2Compressor' object".to_owned()))
+        }
     }
 }