From 9eae60d91343d4df8d87ef7ce578d3aa84c4d08c Mon Sep 17 00:00:00 2001
From: pranaysb <pranaystudies22@gmail.com>
Date: Wed, 22 Jul 2026 19:36:52 +0530
Subject: [PATCH 01/11] Fix NoneType error on os.fork after GC for processors

Assisted-by: Claude Opus 4.6
---
 .../sdk/_shared_internal/__init__.py          |  8 ++++-
 .../sdk/metrics/_internal/export/__init__.py  |  9 +++--
 .../test_periodic_exporting_metric_reader.py  | 36 +++++++++++++++++++
 .../shared_internal/test_batch_processor.py   | 35 ++++++++++++++++++
 4 files changed, 84 insertions(+), 4 deletions(-)

diff --git a/opentelemetry-sdk/src/opentelemetry/sdk/_shared_internal/__init__.py b/opentelemetry-sdk/src/opentelemetry/sdk/_shared_internal/__init__.py
index 3e2b8a263a4..fdfe373bea7 100644
--- a/opentelemetry-sdk/src/opentelemetry/sdk/_shared_internal/__init__.py
+++ b/opentelemetry-sdk/src/opentelemetry/sdk/_shared_internal/__init__.py
@@ -116,7 +116,13 @@ def __init__(
         self._worker_thread.start()
         if hasattr(os, "register_at_fork"):
             weak_reinit = weakref.WeakMethod(self._at_fork_reinit)
-            os.register_at_fork(after_in_child=lambda: weak_reinit()())  # pyright: ignore[reportOptionalCall] pylint: disable=unnecessary-lambda
+
+            def _after_in_child() -> None:
+                reinit = weak_reinit()
+                if reinit is not None:
+                    reinit()
+
+            os.register_at_fork(after_in_child=_after_in_child)
         self._pid = os.getpid()
 
         metrics.register_queue_size(lambda: len(self._queue))
diff --git a/opentelemetry-sdk/src/opentelemetry/sdk/metrics/_internal/export/__init__.py b/opentelemetry-sdk/src/opentelemetry/sdk/metrics/_internal/export/__init__.py
index aee356f78d2..de73538aff1 100644
--- a/opentelemetry-sdk/src/opentelemetry/sdk/metrics/_internal/export/__init__.py
+++ b/opentelemetry-sdk/src/opentelemetry/sdk/metrics/_internal/export/__init__.py
@@ -531,9 +531,12 @@ def __init__(
             if hasattr(os, "register_at_fork"):
                 weak_at_fork = weakref.WeakMethod(self._at_fork_reinit)
 
-                os.register_at_fork(
-                    after_in_child=lambda: weak_at_fork()()  # pylint: disable=unnecessary-lambda
-                )
+                def _after_in_child() -> None:
+                    at_fork = weak_at_fork()
+                    if at_fork is not None:
+                        at_fork()
+
+                os.register_at_fork(after_in_child=_after_in_child)
         elif self._export_interval_millis <= 0:
             raise ValueError(
                 f"interval value {self._export_interval_millis} is invalid \
diff --git a/opentelemetry-sdk/tests/metrics/test_periodic_exporting_metric_reader.py b/opentelemetry-sdk/tests/metrics/test_periodic_exporting_metric_reader.py
index ab8877c21c3..381881c9b24 100644
--- a/opentelemetry-sdk/tests/metrics/test_periodic_exporting_metric_reader.py
+++ b/opentelemetry-sdk/tests/metrics/test_periodic_exporting_metric_reader.py
@@ -5,6 +5,7 @@
 
 import gc
 import math
+import os
 import weakref
 from logging import WARNING
 from time import sleep, time_ns
@@ -307,6 +308,41 @@ def test_metric_exporer_gc(self):
             "The PeriodicExportingMetricReader object created by this test wasn't garbage collected",
         )
 
+    @pytest.mark.skipif(not hasattr(os, "fork"), reason="needs *nix")
+    def test_garbage_collected_processor_does_not_crash_on_fork(self):
+        import os
+        import sys
+
+        exporter = FakeMetricsExporter(
+            preferred_aggregation={
+                Counter: LastValueAggregation(),
+            },
+        )
+        processor = PeriodicExportingMetricReader(exporter)
+        processor.shutdown()
+        del processor
+        gc.collect()
+
+        # The bug causes an unraisable exception to be printed to stderr.
+        # We redirect stderr to a pipe before fork to capture it.
+        r_fd, w_fd = os.pipe()
+
+        pid = os.fork()
+        if pid == 0:
+            os.close(r_fd)
+            os.dup2(w_fd, sys.stderr.fileno())
+            # os.fork() has already run the at_fork hooks.
+            os._exit(0)
+
+        os.close(w_fd)
+        _, status = os.waitpid(pid, 0)
+        self.assertEqual(status, 0)
+
+        child_stderr = os.read(r_fd, 1024).decode("utf-8")
+        os.close(r_fd)
+
+        self.assertNotIn("TypeError", child_stderr)
+
     @patch.dict(
         "os.environ", {OTEL_PYTHON_SDK_INTERNAL_METRICS_ENABLED: "true"}
     )
diff --git a/opentelemetry-sdk/tests/shared_internal/test_batch_processor.py b/opentelemetry-sdk/tests/shared_internal/test_batch_processor.py
index 02337757073..41ef19f5851 100644
--- a/opentelemetry-sdk/tests/shared_internal/test_batch_processor.py
+++ b/opentelemetry-sdk/tests/shared_internal/test_batch_processor.py
@@ -215,6 +215,41 @@ def test_record_processor_is_garbage_collected(
         # Then the reference to the processor should no longer exist
         assert weak_ref() is None
 
+    @unittest.skipUnless(
+        hasattr(os, "fork"),
+        "needs *nix",
+    )
+    def test_garbage_collected_processor_does_not_crash_on_fork(
+        self, batch_processor_class, telemetry
+    ):
+        import sys
+        
+        exporter = Mock()
+        processor = batch_processor_class(exporter)
+        processor.shutdown()
+        del processor
+        gc.collect()
+
+        # The bug causes an unraisable exception to be printed to stderr.
+        # We redirect stderr to a pipe before fork to capture it.
+        r_fd, w_fd = os.pipe()
+
+        pid = os.fork()
+        if pid == 0:
+            os.close(r_fd)
+            os.dup2(w_fd, sys.stderr.fileno())
+            # os.fork() has already run the at_fork hooks.
+            os._exit(0)
+
+        os.close(w_fd)
+        _, status = os.waitpid(pid, 0)
+        assert status == 0
+        
+        child_stderr = os.read(r_fd, 1024).decode("utf-8")
+        os.close(r_fd)
+        
+        assert "TypeError" not in child_stderr
+
     def test_shutdown_allows_1_export_to_finish(
         self, batch_processor_class, telemetry
     ):

From 911346ae8b647ebd51330524e5f9b56d054d3819 Mon Sep 17 00:00:00 2001
From: pranaysb <pranaystudies22@gmail.com>
Date: Wed, 22 Jul 2026 22:39:45 +0530
Subject: [PATCH 02/11] Fix regression tests to correctly capture
 unraisablehook output in child process

---
 .../test_periodic_exporting_metric_reader.py  | 30 +++++++++++++++----
 .../shared_internal/test_batch_processor.py   | 29 +++++++++++++++---
 2 files changed, 50 insertions(+), 9 deletions(-)

diff --git a/opentelemetry-sdk/tests/metrics/test_periodic_exporting_metric_reader.py b/opentelemetry-sdk/tests/metrics/test_periodic_exporting_metric_reader.py
index 381881c9b24..7c13dad2593 100644
--- a/opentelemetry-sdk/tests/metrics/test_periodic_exporting_metric_reader.py
+++ b/opentelemetry-sdk/tests/metrics/test_periodic_exporting_metric_reader.py
@@ -6,6 +6,7 @@
 import gc
 import math
 import os
+import sys
 import weakref
 from logging import WARNING
 from time import sleep, time_ns
@@ -310,9 +311,6 @@ def test_metric_exporer_gc(self):
 
     @pytest.mark.skipif(not hasattr(os, "fork"), reason="needs *nix")
     def test_garbage_collected_processor_does_not_crash_on_fork(self):
-        import os
-        import sys
-
         exporter = FakeMetricsExporter(
             preferred_aggregation={
                 Counter: LastValueAggregation(),
@@ -327,18 +325,40 @@ def test_garbage_collected_processor_does_not_crash_on_fork(self):
         # We redirect stderr to a pipe before fork to capture it.
         r_fd, w_fd = os.pipe()
 
+        # Save original stderr and redirect it to the pipe
+        # We also temporarily restore the default sys.unraisablehook. Pytest overrides
+        # it to capture exceptions in memory, which would be lost on os._exit(0).
+        old_fd = os.dup(sys.stderr.fileno())
+        os.dup2(w_fd, sys.stderr.fileno())
+        old_hook = sys.unraisablehook
+        sys.unraisablehook = sys.__unraisablehook__
+
         pid = os.fork()
         if pid == 0:
             os.close(r_fd)
-            os.dup2(w_fd, sys.stderr.fileno())
             # os.fork() has already run the at_fork hooks.
             os._exit(0)
 
+        # Restore original stderr and hook in parent
+        sys.unraisablehook = old_hook
+        os.dup2(old_fd, sys.stderr.fileno())
+        os.close(old_fd)
         os.close(w_fd)
+
         _, status = os.waitpid(pid, 0)
         self.assertEqual(status, 0)
 
-        child_stderr = os.read(r_fd, 1024).decode("utf-8")
+        os.set_blocking(r_fd, False)
+        child_stderr = b""
+        while True:
+            try:
+                chunk = os.read(r_fd, 4096)
+                if not chunk:
+                    break
+                child_stderr += chunk
+            except BlockingIOError:
+                break
+        child_stderr = child_stderr.decode("utf-8")
         os.close(r_fd)
 
         self.assertNotIn("TypeError", child_stderr)
diff --git a/opentelemetry-sdk/tests/shared_internal/test_batch_processor.py b/opentelemetry-sdk/tests/shared_internal/test_batch_processor.py
index 41ef19f5851..b719e9f66d0 100644
--- a/opentelemetry-sdk/tests/shared_internal/test_batch_processor.py
+++ b/opentelemetry-sdk/tests/shared_internal/test_batch_processor.py
@@ -6,6 +6,7 @@
 import logging
 import multiprocessing
 import os
+import sys
 import threading
 import time
 import unittest
@@ -222,8 +223,6 @@ def test_record_processor_is_garbage_collected(
     def test_garbage_collected_processor_does_not_crash_on_fork(
         self, batch_processor_class, telemetry
     ):
-        import sys
-        
         exporter = Mock()
         processor = batch_processor_class(exporter)
         processor.shutdown()
@@ -233,19 +232,41 @@ def test_garbage_collected_processor_does_not_crash_on_fork(
         # The bug causes an unraisable exception to be printed to stderr.
         # We redirect stderr to a pipe before fork to capture it.
         r_fd, w_fd = os.pipe()
+        
+        # Save original stderr and redirect it to the pipe
+        # We also temporarily restore the default sys.unraisablehook. Pytest overrides
+        # it to capture exceptions in memory, which would be lost on os._exit(0).
+        old_fd = os.dup(sys.stderr.fileno())
+        os.dup2(w_fd, sys.stderr.fileno())
+        old_hook = sys.unraisablehook
+        sys.unraisablehook = sys.__unraisablehook__
 
         pid = os.fork()
         if pid == 0:
             os.close(r_fd)
-            os.dup2(w_fd, sys.stderr.fileno())
             # os.fork() has already run the at_fork hooks.
             os._exit(0)
 
+        # Restore original stderr and hook in parent
+        sys.unraisablehook = old_hook
+        os.dup2(old_fd, sys.stderr.fileno())
+        os.close(old_fd)
         os.close(w_fd)
+
         _, status = os.waitpid(pid, 0)
         assert status == 0
         
-        child_stderr = os.read(r_fd, 1024).decode("utf-8")
+        os.set_blocking(r_fd, False)
+        child_stderr = b""
+        while True:
+            try:
+                chunk = os.read(r_fd, 4096)
+                if not chunk:
+                    break
+                child_stderr += chunk
+            except BlockingIOError:
+                break
+        child_stderr = child_stderr.decode("utf-8")
         os.close(r_fd)
         
         assert "TypeError" not in child_stderr

From ff3e4dd8416f8d5e6a3248ddf544d54af98696d9 Mon Sep 17 00:00:00 2001
From: pranaysb <pranaystudies22@gmail.com>
Date: Thu, 23 Jul 2026 07:08:55 +0530
Subject: [PATCH 03/11] docs: add changelog fragment for fork gc fix

Assisted-by: Google Antigravity
---
 .changelog/5452.fixed | 1 +
 1 file changed, 1 insertion(+)
 create mode 100644 .changelog/5452.fixed

diff --git a/.changelog/5452.fixed b/.changelog/5452.fixed
new file mode 100644
index 00000000000..be06e3e8263
--- /dev/null
+++ b/.changelog/5452.fixed
@@ -0,0 +1 @@
+`opentelemetry-sdk`: fix `TypeError` in `os.fork()` when a `BatchProcessor` or `PeriodicExportingMetricReader` is garbage collected

From 24a7f809876beb6c72592689b93e2b4b618e0480 Mon Sep 17 00:00:00 2001
From: pranaysb <pranaystudies22@gmail.com>
Date: Thu, 23 Jul 2026 07:51:36 +0530
Subject: [PATCH 04/11] docs: rename changelog fragment to match PR number

Assisted-by: Google Antigravity
---
 .changelog/{5452.fixed => 5453.fixed} | 0
 1 file changed, 0 insertions(+), 0 deletions(-)
 rename .changelog/{5452.fixed => 5453.fixed} (100%)

diff --git a/.changelog/5452.fixed b/.changelog/5453.fixed
similarity index 100%
rename from .changelog/5452.fixed
rename to .changelog/5453.fixed

From 057cb3f73bd159bcf54e1328237a686e04302a39 Mon Sep 17 00:00:00 2001
From: pranaysb <pranaystudies22@gmail.com>
Date: Thu, 23 Jul 2026 07:55:42 +0530
Subject: [PATCH 05/11] style: fix trailing whitespace in tests

Assisted-by: Google Antigravity
---
 .../tests/shared_internal/test_batch_processor.py           | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/opentelemetry-sdk/tests/shared_internal/test_batch_processor.py b/opentelemetry-sdk/tests/shared_internal/test_batch_processor.py
index b719e9f66d0..891643fc813 100644
--- a/opentelemetry-sdk/tests/shared_internal/test_batch_processor.py
+++ b/opentelemetry-sdk/tests/shared_internal/test_batch_processor.py
@@ -232,7 +232,7 @@ def test_garbage_collected_processor_does_not_crash_on_fork(
         # The bug causes an unraisable exception to be printed to stderr.
         # We redirect stderr to a pipe before fork to capture it.
         r_fd, w_fd = os.pipe()
-        
+
         # Save original stderr and redirect it to the pipe
         # We also temporarily restore the default sys.unraisablehook. Pytest overrides
         # it to capture exceptions in memory, which would be lost on os._exit(0).
@@ -255,7 +255,7 @@ def test_garbage_collected_processor_does_not_crash_on_fork(
 
         _, status = os.waitpid(pid, 0)
         assert status == 0
-        
+
         os.set_blocking(r_fd, False)
         child_stderr = b""
         while True:
@@ -268,7 +268,7 @@ def test_garbage_collected_processor_does_not_crash_on_fork(
                 break
         child_stderr = child_stderr.decode("utf-8")
         os.close(r_fd)
-        
+
         assert "TypeError" not in child_stderr
 
     def test_shutdown_allows_1_export_to_finish(

From 5334afcdb6d791b5de6b05a8e88c5a883e01157f Mon Sep 17 00:00:00 2001
From: pranaysb <pranaystudies22@gmail.com>
Date: Thu, 23 Jul 2026 07:56:19 +0530
Subject: [PATCH 06/11] test: disable pylint logging-too-few-args in
 test_export

Assisted-by: Google Antigravity
---
 opentelemetry-sdk/tests/logs/test_export.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/opentelemetry-sdk/tests/logs/test_export.py b/opentelemetry-sdk/tests/logs/test_export.py
index 5d8b4328cea..b03e8068c40 100644
--- a/opentelemetry-sdk/tests/logs/test_export.py
+++ b/opentelemetry-sdk/tests/logs/test_export.py
@@ -328,7 +328,7 @@ def test_simple_log_record_processor_custom_single_obj(self):
         # formatting was applied
 
         # string msg with no args - getMessage bypasses formatting and sets the string directly
-        logger.warning("a string with a percent-s: %s")
+        logger.warning("a string with a percent-s: %s")  # pylint: disable=logging-too-few-args
         # string msg with args - getMessage formats args into the msg
         logger.warning("a string with a percent-s: %s", "and arg")
         # non-string msg with args - getMessage stringifies msg and formats args into it

From 7ab64fb5728a4388441907cf7fc14c6270f281df Mon Sep 17 00:00:00 2001
From: S B Pranay <pranaystudies22@gmail.com>
Date: Thu, 23 Jul 2026 13:12:12 +0530
Subject: [PATCH 07/11] Update
 opentelemetry-sdk/src/opentelemetry/sdk/_shared_internal/__init__.py

Co-authored-by: Lukas Hering <40302054+herin049@users.noreply.github.com>
---
 .../src/opentelemetry/sdk/_shared_internal/__init__.py         | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/opentelemetry-sdk/src/opentelemetry/sdk/_shared_internal/__init__.py b/opentelemetry-sdk/src/opentelemetry/sdk/_shared_internal/__init__.py
index fdfe373bea7..5a2a57f8fc0 100644
--- a/opentelemetry-sdk/src/opentelemetry/sdk/_shared_internal/__init__.py
+++ b/opentelemetry-sdk/src/opentelemetry/sdk/_shared_internal/__init__.py
@@ -118,8 +118,7 @@ def __init__(
             weak_reinit = weakref.WeakMethod(self._at_fork_reinit)
 
             def _after_in_child() -> None:
-                reinit = weak_reinit()
-                if reinit is not None:
+                if reinit := weak_reinit():
                     reinit()
 
             os.register_at_fork(after_in_child=_after_in_child)

From 777f5567a662a1a340c95df5a6df1808045e6073 Mon Sep 17 00:00:00 2001
From: S B Pranay <pranaystudies22@gmail.com>
Date: Thu, 23 Jul 2026 13:13:53 +0530
Subject: [PATCH 08/11] Update
 opentelemetry-sdk/src/opentelemetry/sdk/metrics/_internal/export/__init__.py

Co-authored-by: Lukas Hering <40302054+herin049@users.noreply.github.com>
---
 .../src/opentelemetry/sdk/metrics/_internal/export/__init__.py | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/opentelemetry-sdk/src/opentelemetry/sdk/metrics/_internal/export/__init__.py b/opentelemetry-sdk/src/opentelemetry/sdk/metrics/_internal/export/__init__.py
index de73538aff1..8cce878cdba 100644
--- a/opentelemetry-sdk/src/opentelemetry/sdk/metrics/_internal/export/__init__.py
+++ b/opentelemetry-sdk/src/opentelemetry/sdk/metrics/_internal/export/__init__.py
@@ -532,8 +532,7 @@ def __init__(
                 weak_at_fork = weakref.WeakMethod(self._at_fork_reinit)
 
                 def _after_in_child() -> None:
-                    at_fork = weak_at_fork()
-                    if at_fork is not None:
+                    if at_fork := weak_at_fork():
                         at_fork()
 
                 os.register_at_fork(after_in_child=_after_in_child)

From 92133f35a9337cd7e37286c13359200602df8af0 Mon Sep 17 00:00:00 2001
From: pranaysb <pranaystudies22@gmail.com>
Date: Thu, 23 Jul 2026 13:25:27 +0530
Subject: [PATCH 09/11] test: improve robust cleanup and skip logic in fork
 tests

Assisted-by: Google Antigravity
---
 opentelemetry-sdk/tests/logs/test_export.py   |  2 +-
 .../test_periodic_exporting_metric_reader.py  | 41 +++++++++++--------
 .../shared_internal/test_batch_processor.py   | 38 +++++++++--------
 3 files changed, 45 insertions(+), 36 deletions(-)

diff --git a/opentelemetry-sdk/tests/logs/test_export.py b/opentelemetry-sdk/tests/logs/test_export.py
index b03e8068c40..5d8b4328cea 100644
--- a/opentelemetry-sdk/tests/logs/test_export.py
+++ b/opentelemetry-sdk/tests/logs/test_export.py
@@ -328,7 +328,7 @@ def test_simple_log_record_processor_custom_single_obj(self):
         # formatting was applied
 
         # string msg with no args - getMessage bypasses formatting and sets the string directly
-        logger.warning("a string with a percent-s: %s")  # pylint: disable=logging-too-few-args
+        logger.warning("a string with a percent-s: %s")
         # string msg with args - getMessage formats args into the msg
         logger.warning("a string with a percent-s: %s", "and arg")
         # non-string msg with args - getMessage stringifies msg and formats args into it
diff --git a/opentelemetry-sdk/tests/metrics/test_periodic_exporting_metric_reader.py b/opentelemetry-sdk/tests/metrics/test_periodic_exporting_metric_reader.py
index 7c13dad2593..105295e8a55 100644
--- a/opentelemetry-sdk/tests/metrics/test_periodic_exporting_metric_reader.py
+++ b/opentelemetry-sdk/tests/metrics/test_periodic_exporting_metric_reader.py
@@ -309,7 +309,7 @@ def test_metric_exporer_gc(self):
             "The PeriodicExportingMetricReader object created by this test wasn't garbage collected",
         )
 
-    @pytest.mark.skipif(not hasattr(os, "fork"), reason="needs *nix")
+    @pytest.mark.skipif(not hasattr(os, "fork") or not hasattr(os, "register_at_fork"), reason="needs fork and register_at_fork")
     def test_garbage_collected_processor_does_not_crash_on_fork(self):
         exporter = FakeMetricsExporter(
             preferred_aggregation={
@@ -317,10 +317,13 @@ def test_garbage_collected_processor_does_not_crash_on_fork(self):
             },
         )
         processor = PeriodicExportingMetricReader(exporter)
+        w_ref = weakref.ref(processor)
         processor.shutdown()
         del processor
         gc.collect()
 
+        self.assertIsNone(w_ref())
+
         # The bug causes an unraisable exception to be printed to stderr.
         # We redirect stderr to a pipe before fork to capture it.
         r_fd, w_fd = os.pipe()
@@ -329,24 +332,26 @@ def test_garbage_collected_processor_does_not_crash_on_fork(self):
         # We also temporarily restore the default sys.unraisablehook. Pytest overrides
         # it to capture exceptions in memory, which would be lost on os._exit(0).
         old_fd = os.dup(sys.stderr.fileno())
-        os.dup2(w_fd, sys.stderr.fileno())
         old_hook = sys.unraisablehook
-        sys.unraisablehook = sys.__unraisablehook__
-
-        pid = os.fork()
-        if pid == 0:
-            os.close(r_fd)
-            # os.fork() has already run the at_fork hooks.
-            os._exit(0)
-
-        # Restore original stderr and hook in parent
-        sys.unraisablehook = old_hook
-        os.dup2(old_fd, sys.stderr.fileno())
-        os.close(old_fd)
-        os.close(w_fd)
-
-        _, status = os.waitpid(pid, 0)
-        self.assertEqual(status, 0)
+        
+        try:
+            os.dup2(w_fd, sys.stderr.fileno())
+            sys.unraisablehook = sys.__unraisablehook__
+
+            pid = os.fork()
+            if pid == 0:
+                os.close(r_fd)
+                # os.fork() has already run the at_fork hooks.
+                os._exit(0)
+                
+            _, status = os.waitpid(pid, 0)
+            self.assertEqual(status, 0)
+        finally:
+            # Restore original stderr and hook in parent
+            sys.unraisablehook = old_hook
+            os.dup2(old_fd, sys.stderr.fileno())
+            os.close(old_fd)
+            os.close(w_fd)
 
         os.set_blocking(r_fd, False)
         child_stderr = b""
diff --git a/opentelemetry-sdk/tests/shared_internal/test_batch_processor.py b/opentelemetry-sdk/tests/shared_internal/test_batch_processor.py
index 891643fc813..09e4d379a66 100644
--- a/opentelemetry-sdk/tests/shared_internal/test_batch_processor.py
+++ b/opentelemetry-sdk/tests/shared_internal/test_batch_processor.py
@@ -225,10 +225,13 @@ def test_garbage_collected_processor_does_not_crash_on_fork(
     ):
         exporter = Mock()
         processor = batch_processor_class(exporter)
+        w_ref = weakref.ref(processor)
         processor.shutdown()
         del processor
         gc.collect()
 
+        self.assertIsNone(w_ref())
+
         # The bug causes an unraisable exception to be printed to stderr.
         # We redirect stderr to a pipe before fork to capture it.
         r_fd, w_fd = os.pipe()
@@ -237,24 +240,25 @@ def test_garbage_collected_processor_does_not_crash_on_fork(
         # We also temporarily restore the default sys.unraisablehook. Pytest overrides
         # it to capture exceptions in memory, which would be lost on os._exit(0).
         old_fd = os.dup(sys.stderr.fileno())
-        os.dup2(w_fd, sys.stderr.fileno())
         old_hook = sys.unraisablehook
-        sys.unraisablehook = sys.__unraisablehook__
-
-        pid = os.fork()
-        if pid == 0:
-            os.close(r_fd)
-            # os.fork() has already run the at_fork hooks.
-            os._exit(0)
-
-        # Restore original stderr and hook in parent
-        sys.unraisablehook = old_hook
-        os.dup2(old_fd, sys.stderr.fileno())
-        os.close(old_fd)
-        os.close(w_fd)
-
-        _, status = os.waitpid(pid, 0)
-        assert status == 0
+        
+        try:
+            os.dup2(w_fd, sys.stderr.fileno())
+            sys.unraisablehook = sys.__unraisablehook__
+
+            pid = os.fork()
+            if pid == 0:
+                os.close(r_fd)
+                # os.fork() has already run the at_fork hooks.
+                os._exit(0)
+                
+            os.waitpid(pid, 0)
+        finally:
+            # Restore original stderr and hook in parent
+            sys.unraisablehook = old_hook
+            os.dup2(old_fd, sys.stderr.fileno())
+            os.close(old_fd)
+            os.close(w_fd)
 
         os.set_blocking(r_fd, False)
         child_stderr = b""

From 6d7cab140e3cb0ed84a79c0f3f86faa69bfa5a42 Mon Sep 17 00:00:00 2001
From: pranaysb <pranaystudies22@gmail.com>
Date: Thu, 23 Jul 2026 13:25:55 +0530
Subject: [PATCH 10/11] test: fix assert usage in test_batch_processor

Assisted-by: Google Antigravity
---
 opentelemetry-sdk/tests/shared_internal/test_batch_processor.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/opentelemetry-sdk/tests/shared_internal/test_batch_processor.py b/opentelemetry-sdk/tests/shared_internal/test_batch_processor.py
index 09e4d379a66..e03ae0f62b8 100644
--- a/opentelemetry-sdk/tests/shared_internal/test_batch_processor.py
+++ b/opentelemetry-sdk/tests/shared_internal/test_batch_processor.py
@@ -230,7 +230,7 @@ def test_garbage_collected_processor_does_not_crash_on_fork(
         del processor
         gc.collect()
 
-        self.assertIsNone(w_ref())
+        assert w_ref() is None
 
         # The bug causes an unraisable exception to be printed to stderr.
         # We redirect stderr to a pipe before fork to capture it.

From 9791fbcb46cd3dd14b9c27ad0667f96d8eab20a3 Mon Sep 17 00:00:00 2001
From: pranaysb <pranaystudies22@gmail.com>
Date: Thu, 23 Jul 2026 13:44:44 +0530
Subject: [PATCH 11/11] style: fix trailing whitespace in tests again

Assisted-by: Google Antigravity
---
 .../metrics/test_periodic_exporting_metric_reader.py     | 9 ++++++---
 .../tests/shared_internal/test_batch_processor.py        | 4 ++--
 2 files changed, 8 insertions(+), 5 deletions(-)

diff --git a/opentelemetry-sdk/tests/metrics/test_periodic_exporting_metric_reader.py b/opentelemetry-sdk/tests/metrics/test_periodic_exporting_metric_reader.py
index 105295e8a55..1a2a1b319f3 100644
--- a/opentelemetry-sdk/tests/metrics/test_periodic_exporting_metric_reader.py
+++ b/opentelemetry-sdk/tests/metrics/test_periodic_exporting_metric_reader.py
@@ -309,7 +309,10 @@ def test_metric_exporer_gc(self):
             "The PeriodicExportingMetricReader object created by this test wasn't garbage collected",
         )
 
-    @pytest.mark.skipif(not hasattr(os, "fork") or not hasattr(os, "register_at_fork"), reason="needs fork and register_at_fork")
+    @pytest.mark.skipif(
+        not hasattr(os, "fork") or not hasattr(os, "register_at_fork"),
+        reason="needs fork and register_at_fork",
+    )
     def test_garbage_collected_processor_does_not_crash_on_fork(self):
         exporter = FakeMetricsExporter(
             preferred_aggregation={
@@ -333,7 +336,7 @@ def test_garbage_collected_processor_does_not_crash_on_fork(self):
         # it to capture exceptions in memory, which would be lost on os._exit(0).
         old_fd = os.dup(sys.stderr.fileno())
         old_hook = sys.unraisablehook
-        
+
         try:
             os.dup2(w_fd, sys.stderr.fileno())
             sys.unraisablehook = sys.__unraisablehook__
@@ -343,7 +346,7 @@ def test_garbage_collected_processor_does_not_crash_on_fork(self):
                 os.close(r_fd)
                 # os.fork() has already run the at_fork hooks.
                 os._exit(0)
-                
+
             _, status = os.waitpid(pid, 0)
             self.assertEqual(status, 0)
         finally:
diff --git a/opentelemetry-sdk/tests/shared_internal/test_batch_processor.py b/opentelemetry-sdk/tests/shared_internal/test_batch_processor.py
index e03ae0f62b8..91500155cdb 100644
--- a/opentelemetry-sdk/tests/shared_internal/test_batch_processor.py
+++ b/opentelemetry-sdk/tests/shared_internal/test_batch_processor.py
@@ -241,7 +241,7 @@ def test_garbage_collected_processor_does_not_crash_on_fork(
         # it to capture exceptions in memory, which would be lost on os._exit(0).
         old_fd = os.dup(sys.stderr.fileno())
         old_hook = sys.unraisablehook
-        
+
         try:
             os.dup2(w_fd, sys.stderr.fileno())
             sys.unraisablehook = sys.__unraisablehook__
@@ -251,7 +251,7 @@ def test_garbage_collected_processor_does_not_crash_on_fork(
                 os.close(r_fd)
                 # os.fork() has already run the at_fork hooks.
                 os._exit(0)
-                
+
             os.waitpid(pid, 0)
         finally:
             # Restore original stderr and hook in parent