Google Git Google Git
Sign in
chromium/external/github.com/python/cpython/b2b0a337098e60fa9f84df7b53d191fbd8d4fc67/./Lib/test/test_external_inspection.py
blob: d6243c3fc818eab4953600bebc540e4272343eae [file]
import asyncio
import unittest
import os
import textwrap
import contextlib
import importlib
import sys
import socket
import threading
import time
from contextlib import contextmanager
from asyncio import staggered, taskgroups, base_events, tasks
from unittest.mock import ANY
from test.support import (
os_helper,
SHORT_TIMEOUT,
busy_retry,
requires_gil_enabled,
requires_remote_subprocess_debugging,
)
from test.support.import_helper import import_module
from test.support.script_helper import make_script
from test.support.socket_helper import find_unused_port
import subprocess
# Profiling mode constants
PROFILING_MODE_WALL = 0
PROFILING_MODE_CPU = 1
PROFILING_MODE_GIL = 2
PROFILING_MODE_ALL = 3
PROFILING_MODE_EXCEPTION = 4
# Thread status flags
THREAD_STATUS_HAS_GIL = 1 << 0
THREAD_STATUS_ON_CPU = 1 << 1
THREAD_STATUS_UNKNOWN = 1 << 2
THREAD_STATUS_HAS_EXCEPTION = 1 << 4
# Maximum number of retry attempts for operations that may fail transiently
MAX_TRIES = 10
RETRY_DELAY = 0.1
# Exceptions that can occur transiently when reading from a live process
TRANSIENT_ERRORS = (OSError, RuntimeError, UnicodeDecodeError)
try:
from concurrent import interpreters
except ImportError:
interpreters = None
PROCESS_VM_READV_SUPPORTED = False
try:
from _remote_debugging import PROCESS_VM_READV_SUPPORTED
from _remote_debugging import RemoteUnwinder
from _remote_debugging import FrameInfo, CoroInfo, TaskInfo
except ImportError:
raise unittest.SkipTest(
"Test only runs when _remote_debugging is available"
)
# ============================================================================
# Module-level helper functions
# ============================================================================
def _make_test_script(script_dir, script_basename, source):
to_return = make_script(script_dir, script_basename, source)
importlib.invalidate_caches()
return to_return
def _create_server_socket(port, backlog=1):
"""Create and configure a server socket for test communication."""
server_socket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
server_socket.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
server_socket.bind(("localhost", port))
server_socket.settimeout(SHORT_TIMEOUT)
server_socket.listen(backlog)
return server_socket
def _wait_for_signal(sock, expected_signals, timeout=SHORT_TIMEOUT):
"""
Wait for expected signal(s) from a socket with proper timeout and EOF handling.
Args:
sock: Connected socket to read from
expected_signals: Single bytes object or list of bytes objects to wait for
timeout: Socket timeout in seconds
Returns:
bytes: Complete accumulated response buffer
Raises:
RuntimeError: If connection closed before signal received or timeout
"""
if isinstance(expected_signals, bytes):
expected_signals = [expected_signals]
sock.settimeout(timeout)
buffer = b""
while True:
# Check if all expected signals are in buffer
if all(sig in buffer for sig in expected_signals):
return buffer
try:
chunk = sock.recv(4096)
if not chunk:
# EOF - connection closed
raise RuntimeError(
f"Connection closed before receiving expected signals. "
f"Expected: {expected_signals}, Got: {buffer[-200:]!r}"
)
buffer += chunk
except socket.timeout:
raise RuntimeError(
f"Timeout waiting for signals. "
f"Expected: {expected_signals}, Got: {buffer[-200:]!r}"
)
def _wait_for_n_signals(sock, signal_pattern, count, timeout=SHORT_TIMEOUT):
"""
Wait for N occurrences of a signal pattern.
Args:
sock: Connected socket to read from
signal_pattern: bytes pattern to count (e.g., b"ready")
count: Number of occurrences expected
timeout: Socket timeout in seconds
Returns:
bytes: Complete accumulated response buffer
Raises:
RuntimeError: If connection closed or timeout before receiving all signals
"""
sock.settimeout(timeout)
buffer = b""
found_count = 0
while found_count < count:
try:
chunk = sock.recv(4096)
if not chunk:
raise RuntimeError(
f"Connection closed after {found_count}/{count} signals. "
f"Last 200 bytes: {buffer[-200:]!r}"
)
buffer += chunk
# Count occurrences in entire buffer
found_count = buffer.count(signal_pattern)
except socket.timeout:
raise RuntimeError(
f"Timeout waiting for {count} signals (found {found_count}). "
f"Last 200 bytes: {buffer[-200:]!r}"
)
return buffer
@contextmanager
def _managed_subprocess(args, timeout=SHORT_TIMEOUT):
"""
Context manager for subprocess lifecycle management.
Ensures process is properly terminated and cleaned up even on exceptions.
Uses graceful termination first, then forceful kill if needed.
"""
p = subprocess.Popen(args)
try:
yield p
finally:
try:
p.terminate()
try:
p.wait(timeout=timeout)
except subprocess.TimeoutExpired:
p.kill()
try:
p.wait(timeout=timeout)
except subprocess.TimeoutExpired:
pass # Process refuses to die, nothing more we can do
except OSError:
pass # Process already dead
def _cleanup_sockets(*sockets):
"""Safely close multiple sockets, ignoring errors."""
for sock in sockets:
if sock is not None:
try:
sock.close()
except OSError:
pass
# ============================================================================
# Decorators and skip conditions
# ============================================================================
skip_if_not_supported = unittest.skipIf(
(
sys.platform != "darwin"
and sys.platform != "linux"
and sys.platform != "win32"
),
"Test only runs on Linux, Windows and MacOS",
)
def requires_subinterpreters(meth):
"""Decorator to skip a test if subinterpreters are not supported."""
return unittest.skipIf(interpreters is None, "subinterpreters required")(
meth
)
# ============================================================================
# Simple wrapper functions for RemoteUnwinder
# ============================================================================
def get_stack_trace(pid):
for _ in busy_retry(SHORT_TIMEOUT):
try:
unwinder = RemoteUnwinder(pid, all_threads=True, debug=True)
return unwinder.get_stack_trace()
except RuntimeError as e:
continue
raise RuntimeError("Failed to get stack trace after retries")
def get_async_stack_trace(pid):
for _ in busy_retry(SHORT_TIMEOUT):
try:
unwinder = RemoteUnwinder(pid, debug=True)
return unwinder.get_async_stack_trace()
except RuntimeError as e:
continue
raise RuntimeError("Failed to get async stack trace after retries")
def get_all_awaited_by(pid):
for _ in busy_retry(SHORT_TIMEOUT):
try:
unwinder = RemoteUnwinder(pid, debug=True)
return unwinder.get_all_awaited_by()
except RuntimeError as e:
continue
raise RuntimeError("Failed to get all awaited_by after retries")
def _get_stack_trace_with_retry(unwinder, timeout=SHORT_TIMEOUT, condition=None):
"""Get stack trace from an existing unwinder with retry for transient errors.
This handles the case where we want to reuse an existing RemoteUnwinder
instance but still handle transient failures like "Failed to parse initial
frame in chain" that can occur when sampling at an inopportune moment.
If condition is provided, keeps retrying until condition(traces) is True.
"""
last_error = None
for _ in busy_retry(timeout):
try:
traces = unwinder.get_stack_trace()
if condition is None or condition(traces):
return traces
# Condition not met yet, keep retrying
except TRANSIENT_ERRORS as e:
last_error = e
continue
if last_error:
raise RuntimeError(
f"Failed to get stack trace after retries: {last_error}"
)
raise RuntimeError("Condition never satisfied within timeout")
# ============================================================================
# Base test class with shared infrastructure
# ============================================================================
class RemoteInspectionTestBase(unittest.TestCase):
"""Base class for remote inspection tests with common helpers."""
maxDiff = None
def _run_script_and_get_trace(
self,
script,
trace_func,
wait_for_signals=None,
port=None,
backlog=1,
):
"""
Common pattern: run a script, wait for signals, get trace.
Args:
script: Script content (will be formatted with port if {port} present)
trace_func: Function to call with pid to get trace (e.g., get_stack_trace)
wait_for_signals: Signal(s) to wait for before getting trace
port: Port to use (auto-selected if None)
backlog: Socket listen backlog
Returns:
tuple: (trace_result, script_name)
"""
if port is None:
port = find_unused_port()
# Format script with port if needed
if "{port}" in script or "{{port}}" in script:
script = script.replace("{{port}}", "{port}").format(port=port)
with os_helper.temp_dir() as work_dir:
script_dir = os.path.join(work_dir, "script_pkg")
os.mkdir(script_dir)
server_socket = _create_server_socket(port, backlog)
script_name = _make_test_script(script_dir, "script", script)
client_socket = None
try:
with _managed_subprocess([sys.executable, script_name]) as p:
client_socket, _ = server_socket.accept()
server_socket.close()
server_socket = None
if wait_for_signals:
_wait_for_signal(client_socket, wait_for_signals)
trace = trace_func(p.pid)
return trace, script_name
finally:
_cleanup_sockets(client_socket, server_socket)
@contextmanager
def _target_process(self, script_body):
"""Context manager for running a target process with socket sync."""
port = find_unused_port()
script = f"""\
import socket
sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
sock.connect(('localhost', {port}))
{textwrap.dedent(script_body)}
"""
with os_helper.temp_dir() as work_dir:
script_dir = os.path.join(work_dir, "script_pkg")
os.mkdir(script_dir)
server_socket = _create_server_socket(port)
script_name = _make_test_script(script_dir, "script", script)
client_socket = None
try:
with _managed_subprocess([sys.executable, script_name]) as p:
client_socket, _ = server_socket.accept()
server_socket.close()
server_socket = None
def make_unwinder(cache_frames=True):
return RemoteUnwinder(
p.pid, all_threads=True, cache_frames=cache_frames
)
yield p, client_socket, make_unwinder
finally:
_cleanup_sockets(client_socket, server_socket)
def _find_frame_in_trace(self, stack_trace, predicate):
"""
Find a frame matching predicate in stack trace.
Args:
stack_trace: List of InterpreterInfo objects
predicate: Function(frame) -> bool
Returns:
FrameInfo or None
"""
for interpreter_info in stack_trace:
for thread_info in interpreter_info.threads:
for frame in thread_info.frame_info:
if predicate(frame):
return frame
return None
def _find_thread_by_id(self, stack_trace, thread_id):
"""Find a thread by its native thread ID."""
for interpreter_info in stack_trace:
for thread_info in interpreter_info.threads:
if thread_info.thread_id == thread_id:
return thread_info
return None
def _find_thread_with_frame(self, stack_trace, frame_predicate):
"""Find a thread containing a frame matching predicate."""
for interpreter_info in stack_trace:
for thread_info in interpreter_info.threads:
for frame in thread_info.frame_info:
if frame_predicate(frame):
return thread_info
return None
def _get_thread_statuses(self, stack_trace):
"""Extract thread_id -> status mapping from stack trace."""
statuses = {}
for interpreter_info in stack_trace:
for thread_info in interpreter_info.threads:
statuses[thread_info.thread_id] = thread_info.status
return statuses
def _get_task_id_map(self, stack_trace):
"""Create task_id -> task mapping from async stack trace."""
return {task.task_id: task for task in stack_trace[0].awaited_by}
def _get_awaited_by_relationships(self, stack_trace):
"""Extract task name to awaited_by set mapping."""
id_to_task = self._get_task_id_map(stack_trace)
return {
task.task_name: set(
id_to_task[awaited.task_name].task_name
for awaited in task.awaited_by
)
for task in stack_trace[0].awaited_by
}
def _extract_coroutine_stacks(self, stack_trace):
"""Extract and format coroutine stacks from tasks."""
return {
task.task_name: sorted(
tuple(tuple(frame) for frame in coro.call_stack)
for coro in task.coroutine_stack
)
for task in stack_trace[0].awaited_by
}
@staticmethod
def _frame_to_lineno_tuple(frame):
"""Convert frame to (filename, lineno, funcname, opcode) tuple.
This extracts just the line number from the location, ignoring column
offsets which can vary due to sampling timing (e.g., when two statements
are on the same line, the sample might catch either one).
"""
filename, location, funcname, opcode = frame
return (filename, location.lineno, funcname, opcode)
def _extract_coroutine_stacks_lineno_only(self, stack_trace):
"""Extract coroutine stacks with line numbers only (no column offsets).
Use this for tests where sampling timing can cause column offset
variations (e.g., 'expr1; expr2' on the same line).
"""
return {
task.task_name: sorted(
tuple(self._frame_to_lineno_tuple(frame) for frame in coro.call_stack)
for coro in task.coroutine_stack
)
for task in stack_trace[0].awaited_by
}
# ============================================================================
# Test classes
# ============================================================================
@requires_remote_subprocess_debugging()
class TestSelfStackTrace(RemoteInspectionTestBase):
def _extract_coroutine_funcnames(self, trace):
return {
task.task_name: [
frame.funcname.rpartition(".")[2]
for coro in task.coroutine_stack
for frame in coro.call_stack
]
for info in trace
for task in info.awaited_by
}
@skip_if_not_supported
def test_long_task_name_is_truncated(self):
# gh-157788
async def main():
asyncio.create_task(asyncio.sleep(10_000), name="x" * 300)
await asyncio.sleep(0)
names = [
task.task_name
for info in RemoteUnwinder(os.getpid()).get_all_awaited_by()
for task in info.awaited_by
]
return asyncio.current_task().get_name(), names
main_name, names = asyncio.run(main())
self.assertIn(main_name, names)
self.assertEqual([len(n) for n in names if n.startswith("x")], [255])
@skip_if_not_supported
def test_recursive_coroutine_stack_is_not_truncated(self):
# gh-158522
async def rec(n):
if n:
return await rec(n - 1)
return [
frame.funcname.rpartition(".")[2]
for task in RemoteUnwinder(
os.getpid()).get_async_stack_trace()[0].awaited_by
for coro in task.coroutine_stack
for frame in coro.call_stack
]
self.assertEqual(asyncio.run(rec(3)), ["rec"] * 4)
@skip_if_not_supported
def test_async_generator_stack_is_not_truncated(self):
# gh-159620
async def agen():
await asyncio.sleep(10_000)
yield
async def agen_with_cleanup():
try:
yield
finally:
await asyncio.sleep(10_000)
async def outer_agen():
async for _ in agen():
yield
async def consumer(gen):
async for _ in gen:
pass
async def main():
g = agen_with_cleanup()
await anext(g)
async_for_task = asyncio.create_task(consumer(agen()), name="async for")
nested_task = asyncio.create_task(
consumer(outer_agen()), name="nested async for")
anext_task = asyncio.create_task(anext(agen()), name="anext")
aclose_task = asyncio.create_task(g.aclose(), name="aclose")
await asyncio.sleep(0)
return RemoteUnwinder(os.getpid()).get_all_awaited_by()
stacks = self._extract_coroutine_funcnames(asyncio.run(main()))
self.assertEqual(stacks["async for"], ["sleep", "agen", "consumer"])
self.assertEqual(stacks["nested async for"],
["sleep", "agen", "outer_agen", "consumer"])
self.assertEqual(stacks["anext"], ["sleep", "agen"])
self.assertEqual(stacks["aclose"], ["sleep", "agen_with_cleanup"])
@skip_if_not_supported
def test_async_generator_waiter_in_async_stack_trace(self):
# gh-159620
async def agen(task):
await task
yield
async def main():
waiter_task = asyncio.create_task(
anext(agen(asyncio.current_task())), name="anext")
await asyncio.sleep(0)
return RemoteUnwinder(os.getpid()).get_async_stack_trace()
stacks = self._extract_coroutine_funcnames(asyncio.run(main()))
self.assertEqual(stacks["anext"], ["agen"])
@skip_if_not_supported
def test_async_generator_running_task_stack(self):
# gh-159620
async def agen():
yield RemoteUnwinder(os.getpid()).get_async_stack_trace()
async def main():
return await asyncio.create_task(anext(agen()), name="anext")
stacks = self._extract_coroutine_funcnames(asyncio.run(main()))
self.assertEqual(stacks["anext"], ["agen"])
@skip_if_not_supported
def test_class_named_like_async_generator_wrapper_is_not_walked(self):
# gh-159620
async def decoy():
await asyncio.sleep(10_000)
class async_generator_asend:
__slots__ = ("gen",)
def __init__(self, gen):
self.gen = gen
def __await__(self):
return self
def __next__(self):
return None
async def consumer(aw):
await aw
async def main():
with contextlib.closing(decoy()) as gen:
consumer_task = asyncio.create_task(
consumer(async_generator_asend(gen)), name="consumer")
await asyncio.sleep(0)
return RemoteUnwinder(os.getpid()).get_all_awaited_by()
stacks = self._extract_coroutine_funcnames(asyncio.run(main()))
self.assertEqual(stacks["consumer"], ["consumer"])
@skip_if_not_supported
@unittest.skipIf(
sys.platform == "linux" and not PROCESS_VM_READV_SUPPORTED,
"Test only runs on Linux with process_vm_readv support",
)
def test_self_trace_with_large_linetable(self):
script = textwrap.dedent("""\
import os
import _remote_debugging
assignments = "\\n".join(
f"value_{i} = {i}" for i in range(1000)
)
expected_lineno = len(assignments.splitlines()) + 1
source = (
f"{assignments}\\n"
"stack_trace = "
"_remote_debugging.RemoteUnwinder(os.getpid()).get_stack_trace()\\n"
)
code = compile(source, "large_linetable.py", "exec")
assert len(code.co_linetable) > 4096, len(code.co_linetable)
namespace = {"os": os, "_remote_debugging": _remote_debugging}
exec(code, namespace)
large_linetable_frames = [
frame
for interpreter in namespace["stack_trace"]
for thread in interpreter.threads
for frame in thread.frame_info
if frame.filename == "large_linetable.py"
]
assert len(large_linetable_frames) == 1, large_linetable_frames
assert large_linetable_frames[0].location.lineno == expected_lineno, (
large_linetable_frames[0]
)
""")
result = subprocess.run(
[sys.executable, "-c", script],
capture_output=True,
text=True,
timeout=SHORT_TIMEOUT,
)
self.assertEqual(
result.returncode, 0,
f"stdout: {result.stdout}\nstderr: {result.stderr}"
)
@requires_remote_subprocess_debugging()
class TestGetStackTrace(RemoteInspectionTestBase):
@skip_if_not_supported
@unittest.skipIf(
sys.platform == "linux" and not PROCESS_VM_READV_SUPPORTED,
"Test only runs on Linux with process_vm_readv support",
)
def test_remote_stack_trace(self):
port = find_unused_port()
script = textwrap.dedent(
f"""\
import time, sys, socket, threading
sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
sock.connect(('localhost', {port}))
def bar():
for x in range(100):
if x == 50:
baz()
def baz():
foo()
def foo():
sock.sendall(b"ready:thread\\n"); time.sleep(10_000)
t = threading.Thread(target=bar)
t.start()
sock.sendall(b"ready:main\\n"); t.join()
"""
)
with os_helper.temp_dir() as work_dir:
script_dir = os.path.join(work_dir, "script_pkg")
os.mkdir(script_dir)
server_socket = _create_server_socket(port)
script_name = _make_test_script(script_dir, "script", script)
client_socket = None
try:
with _managed_subprocess([sys.executable, script_name]) as p:
client_socket, _ = server_socket.accept()
server_socket.close()
server_socket = None
_wait_for_signal(
client_socket, [b"ready:main", b"ready:thread"]
)
stack_trace = get_stack_trace(p.pid)
# Find expected thread stack by funcname
found_thread = self._find_thread_with_frame(
stack_trace,
lambda f: f.funcname == "foo" and f.location.lineno == 15,
)
self.assertIsNotNone(
found_thread, "Expected thread stack trace not found"
)
# Check the funcnames in order
funcnames = [f.funcname for f in found_thread.frame_info]
self.assertEqual(
funcnames[:6],
["foo", "baz", "bar", "Thread.run", "Thread._bootstrap_inner", "Thread._bootstrap"]
)
# Check main thread
found_main = self._find_frame_in_trace(
stack_trace,
lambda f: f.funcname == "<module>" and f.location.lineno == 19,
)
self.assertIsNotNone(
found_main, "Main thread stack trace not found"
)
finally:
_cleanup_sockets(client_socket, server_socket)
@skip_if_not_supported
@unittest.skipIf(
sys.platform == "linux" and not PROCESS_VM_READV_SUPPORTED,
"Test only runs on Linux with process_vm_readv support",
)
def test_self_trace_after_ctypes_import(self):
"""Test that RemoteUnwinder works on the same process after _ctypes import.
When _ctypes is imported, it may call dlopen on the libpython shared
library, creating a duplicate mapping in the process address space.
The remote debugging code must skip these uninitialized duplicate
mappings and find the real PyRuntime. See gh-144563.
"""
# Skip the test if the _ctypes module is missing.
import_module("_ctypes")
# Run the test in a subprocess to avoid side effects
script = textwrap.dedent("""\
import os
import _remote_debugging
# Should work before _ctypes import
unwinder = _remote_debugging.RemoteUnwinder(os.getpid())
import _ctypes
# Should still work after _ctypes import (gh-144563)
unwinder = _remote_debugging.RemoteUnwinder(os.getpid())
""")
result = subprocess.run(
[sys.executable, "-c", script],
capture_output=True,
text=True,
timeout=SHORT_TIMEOUT,
)
self.assertEqual(
result.returncode, 0,
f"stdout: {result.stdout}\nstderr: {result.stderr}"
)
@skip_if_not_supported
@unittest.skipIf(
sys.platform == "linux" and not PROCESS_VM_READV_SUPPORTED,
"Test only runs on Linux with process_vm_readv support",
)
def test_remote_stack_trace_non_ascii_names(self):
# Exercise each PyUnicode kind (1-byte non-ASCII, 2-byte BMP,
# 4-byte non-BMP) for both the filename and the function name
# reported in the stack trace.
latin1 = "zażółć" # 1-byte non-ASCII (forces non-ASCII path)
bmp = "λάμβδα" # 2-byte BMP
astral = "𐌀𐌁𐌂𐌃" # 4-byte non-BMP (Old Italic; XID, no NFKC fold)
func_name = f"{latin1}_{bmp}_{astral}"
script_basename = f"mod_{latin1}_{bmp}_{astral}"
port = find_unused_port()
script = textwrap.dedent(
f"""\
import socket
import time
sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
sock.connect(('localhost', {port}))
def {func_name}():
sock.sendall(b"ready")
time.sleep(10_000)
{func_name}()
"""
)
with os_helper.temp_dir() as work_dir:
script_dir = os.path.join(work_dir, "script_pkg")
os.mkdir(script_dir)
script_name = _make_test_script(script_dir, script_basename, script)
server_socket = _create_server_socket(port)
client_socket = None
try:
p = subprocess.Popen([sys.executable, script_name])
client_socket, _ = server_socket.accept()
server_socket.close()
_wait_for_signal(client_socket, b"ready")
stack_trace = get_stack_trace(p.pid)
except PermissionError:
self.skipTest("Insufficient permissions to read the stack trace")
finally:
if client_socket is not None:
client_socket.close()
p.kill()
p.wait(timeout=SHORT_TIMEOUT)
frames = [
frame
for interp in stack_trace
for thread in interp.threads
for frame in thread.frame_info
]
target = next(
(f for f in frames if f.funcname == func_name), None
)
self.assertIsNotNone(
target,
f"Frame for {func_name!r} missing; got "
f"{[(f.filename, f.funcname) for f in frames]}",
)
self.assertEqual(target.filename, script_name)
@skip_if_not_supported
@unittest.skipIf(
sys.platform == "linux" and not PROCESS_VM_READV_SUPPORTED,
"Test only runs on Linux with process_vm_readv support",
)
def test_async_remote_stack_trace(self):
port = find_unused_port()
script = textwrap.dedent(
f"""\
import asyncio
import time
import sys
import socket
sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
sock.connect(('localhost', {port}))
def c5():
sock.sendall(b"ready"); time.sleep(10_000)
async def c4():
await asyncio.sleep(0)
c5()
async def c3():
await c4()
async def c2():
await c3()
async def c1(task):
await task
async def main():
async with asyncio.TaskGroup() as tg:
task = tg.create_task(c2(), name="c2_root")
tg.create_task(c1(task), name="sub_main_1")
tg.create_task(c1(task), name="sub_main_2")
def new_eager_loop():
loop = asyncio.new_event_loop()
eager_task_factory = asyncio.create_eager_task_factory(
asyncio.Task)
loop.set_task_factory(eager_task_factory)
return loop
asyncio.run(main(), loop_factory={{TASK_FACTORY}})
"""
)
for task_factory_variant in "asyncio.new_event_loop", "new_eager_loop":
with (
self.subTest(task_factory_variant=task_factory_variant),
os_helper.temp_dir() as work_dir,
):
script_dir = os.path.join(work_dir, "script_pkg")
os.mkdir(script_dir)
server_socket = _create_server_socket(port)
script_name = _make_test_script(
script_dir,
"script",
script.format(TASK_FACTORY=task_factory_variant),
)
client_socket = None
try:
with _managed_subprocess(
[sys.executable, script_name]
) as p:
client_socket, _ = server_socket.accept()
server_socket.close()
server_socket = None
response = _wait_for_signal(client_socket, b"ready")
self.assertIn(b"ready", response)
stack_trace = get_async_stack_trace(p.pid)
# Check all tasks are present
tasks_names = [
task.task_name
for task in stack_trace[0].awaited_by
]
for task_name in [
"c2_root",
"sub_main_1",
"sub_main_2",
]:
self.assertIn(task_name, tasks_names)
# Check awaited_by relationships
relationships = self._get_awaited_by_relationships(
stack_trace
)
self.assertEqual(
relationships,
{
"c2_root": {
"Task-1",
"sub_main_1",
"sub_main_2",
},
"Task-1": set(),
"sub_main_1": {"Task-1"},
"sub_main_2": {"Task-1"},
},
)
# Check coroutine stacks (using line numbers only to avoid
# flakiness from column offset variations when sampling
# catches different statements on the same line)
coroutine_stacks = self._extract_coroutine_stacks_lineno_only(
stack_trace
)
self.assertEqual(
coroutine_stacks,
{
"Task-1": [
(
(taskgroups.__file__, ANY, "TaskGroup._aexit", None),
(taskgroups.__file__, ANY, "TaskGroup.__aexit__", None),
(script_name, 26, "main", None),
)
],
"c2_root": [
(
(script_name, 10, "c5", None),
(script_name, 14, "c4", None),
(script_name, 17, "c3", None),
(script_name, 20, "c2", None),
)
],
"sub_main_1": [
((script_name, 23, "c1", None),)
],
"sub_main_2": [
((script_name, 23, "c1", None),)
],
},
)
# Check awaited_by coroutine stacks (line numbers only)
id_to_task = self._get_task_id_map(stack_trace)
awaited_by_coroutine_stacks = {
task.task_name: sorted(
(
id_to_task[coro.task_name].task_name,
tuple(
self._frame_to_lineno_tuple(frame)
for frame in coro.call_stack
),
)
for coro in task.awaited_by
)
for task in stack_trace[0].awaited_by
}
self.assertEqual(
awaited_by_coroutine_stacks,
{
"Task-1": [],
"c2_root": [
(
"Task-1",
(
(taskgroups.__file__, ANY, "TaskGroup._aexit", None),
(taskgroups.__file__, ANY, "TaskGroup.__aexit__", None),
(script_name, 26, "main", None),
),
),
(
"sub_main_1",
((script_name, 23, "c1", None),),
),
(
"sub_main_2",
((script_name, 23, "c1", None),),
),
],
"sub_main_1": [
(
"Task-1",
(
(taskgroups.__file__, ANY, "TaskGroup._aexit", None),
(taskgroups.__file__, ANY, "TaskGroup.__aexit__", None),
(script_name, 26, "main", None),
),
)
],
"sub_main_2": [
(
"Task-1",
(
(taskgroups.__file__, ANY, "TaskGroup._aexit", None),
(taskgroups.__file__, ANY, "TaskGroup.__aexit__", None),
(script_name, 26, "main", None),
),
)
],
},
)
finally:
_cleanup_sockets(client_socket, server_socket)
@skip_if_not_supported
@unittest.skipIf(
sys.platform == "linux" and not PROCESS_VM_READV_SUPPORTED,
"Test only runs on Linux with process_vm_readv support",
)
def test_asyncgen_remote_stack_trace(self):
port = find_unused_port()
script = textwrap.dedent(
f"""\
import asyncio
import time
import sys
import socket
sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
sock.connect(('localhost', {port}))
async def gen_nested_call():
sock.sendall(b"ready"); time.sleep(10_000)
async def gen():
for num in range(2):
yield num
if num == 1:
await gen_nested_call()
async def main():
async for el in gen():
pass
asyncio.run(main())
"""
)
with os_helper.temp_dir() as work_dir:
script_dir = os.path.join(work_dir, "script_pkg")
os.mkdir(script_dir)
server_socket = _create_server_socket(port)
script_name = _make_test_script(script_dir, "script", script)
client_socket = None
try:
with _managed_subprocess([sys.executable, script_name]) as p:
client_socket, _ = server_socket.accept()
server_socket.close()
server_socket = None
response = _wait_for_signal(client_socket, b"ready")
self.assertIn(b"ready", response)
stack_trace = get_async_stack_trace(p.pid)
# For this simple asyncgen test, we only expect one task
self.assertEqual(len(stack_trace[0].awaited_by), 1)
task = stack_trace[0].awaited_by[0]
self.assertEqual(task.task_name, "Task-1")
# Check the coroutine stack (using line numbers only to avoid
# flakiness from column offset variations when sampling
# catches different statements on the same line)
coroutine_stack = sorted(
tuple(self._frame_to_lineno_tuple(frame) for frame in coro.call_stack)
for coro in task.coroutine_stack
)
self.assertEqual(
coroutine_stack,
[
(
(script_name, 10, "gen_nested_call", None),
(script_name, 16, "gen", None),
(script_name, 19, "main", None),
)
],
)
# No awaited_by relationships expected
self.assertEqual(task.awaited_by, [])
finally:
_cleanup_sockets(client_socket, server_socket)
@skip_if_not_supported
@unittest.skipIf(
sys.platform == "linux" and not PROCESS_VM_READV_SUPPORTED,
"Test only runs on Linux with process_vm_readv support",
)
def test_async_gather_remote_stack_trace(self):
port = find_unused_port()
script = textwrap.dedent(
f"""\
import asyncio
import time
import sys
import socket
sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
sock.connect(('localhost', {port}))
async def deep():
await asyncio.sleep(0)
sock.sendall(b"ready"); time.sleep(10_000)
async def c1():
await asyncio.sleep(0)
await deep()
async def c2():
await asyncio.sleep(0)
async def main():
await asyncio.gather(c1(), c2())
asyncio.run(main())
"""
)
with os_helper.temp_dir() as work_dir:
script_dir = os.path.join(work_dir, "script_pkg")
os.mkdir(script_dir)
server_socket = _create_server_socket(port)
script_name = _make_test_script(script_dir, "script", script)
client_socket = None
try:
with _managed_subprocess([sys.executable, script_name]) as p:
client_socket, _ = server_socket.accept()
server_socket.close()
server_socket = None
response = _wait_for_signal(client_socket, b"ready")
self.assertIn(b"ready", response)
stack_trace = get_async_stack_trace(p.pid)
# Check all tasks are present
tasks_names = [
task.task_name for task in stack_trace[0].awaited_by
]
for task_name in ["Task-1", "Task-2"]:
self.assertIn(task_name, tasks_names)
# Check awaited_by relationships
relationships = self._get_awaited_by_relationships(
stack_trace
)
self.assertEqual(
relationships,
{
"Task-1": set(),
"Task-2": {"Task-1"},
},
)
# Check coroutine stacks (using line numbers only to avoid
# flakiness from column offset variations when sampling
# catches different statements on the same line)
coroutine_stacks = self._extract_coroutine_stacks_lineno_only(
stack_trace
)
self.assertEqual(
coroutine_stacks,
{
"Task-1": [((script_name, 21, "main", None),)],
"Task-2": [
(
(script_name, 11, "deep", None),
(script_name, 15, "c1", None),
)
],
},
)
# Check awaited_by coroutine stacks (line numbers only)
id_to_task = self._get_task_id_map(stack_trace)
awaited_by_coroutine_stacks = {
task.task_name: sorted(
(
id_to_task[coro.task_name].task_name,
tuple(
self._frame_to_lineno_tuple(frame) for frame in coro.call_stack
),
)
for coro in task.awaited_by
)
for task in stack_trace[0].awaited_by
}
self.assertEqual(
awaited_by_coroutine_stacks,
{
"Task-1": [],
"Task-2": [
("Task-1", ((script_name, 21, "main", None),))
],
},
)
finally:
_cleanup_sockets(client_socket, server_socket)
@skip_if_not_supported
@unittest.skipIf(
sys.platform == "linux" and not PROCESS_VM_READV_SUPPORTED,
"Test only runs on Linux with process_vm_readv support",
)
def test_async_staggered_race_remote_stack_trace(self):
port = find_unused_port()
script = textwrap.dedent(
f"""\
import asyncio.staggered
import time
import sys
import socket
sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
sock.connect(('localhost', {port}))
async def deep():
await asyncio.sleep(0)
sock.sendall(b"ready"); time.sleep(10_000)
async def c1():
await asyncio.sleep(0)
await deep()
async def c2():
await asyncio.sleep(10_000)
async def main():
await asyncio.staggered.staggered_race(
[c1, c2],
delay=None,
)
asyncio.run(main())
"""
)
with os_helper.temp_dir() as work_dir:
script_dir = os.path.join(work_dir, "script_pkg")
os.mkdir(script_dir)
server_socket = _create_server_socket(port)
script_name = _make_test_script(script_dir, "script", script)
client_socket = None
try:
with _managed_subprocess([sys.executable, script_name]) as p:
client_socket, _ = server_socket.accept()
server_socket.close()
server_socket = None
response = _wait_for_signal(client_socket, b"ready")
self.assertIn(b"ready", response)
stack_trace = get_async_stack_trace(p.pid)
# Check all tasks are present
tasks_names = [
task.task_name for task in stack_trace[0].awaited_by
]
for task_name in ["Task-1", "Task-2"]:
self.assertIn(task_name, tasks_names)
# Check awaited_by relationships
relationships = self._get_awaited_by_relationships(
stack_trace
)
self.assertEqual(
relationships,
{
"Task-1": set(),
"Task-2": {"Task-1"},
},
)
# Check coroutine stacks (using line numbers only to avoid
# flakiness from column offset variations when sampling
# catches different statements on the same line)
coroutine_stacks = self._extract_coroutine_stacks_lineno_only(
stack_trace
)
self.assertEqual(
coroutine_stacks,
{
"Task-1": [
(
(staggered.__file__, ANY, "staggered_race", None),
(script_name, 21, "main", None),
)
],
"Task-2": [
(
(script_name, 11, "deep", None),
(script_name, 15, "c1", None),
(staggered.__file__, ANY, "staggered_race.<locals>.run_one_coro", None),
)
],
},
)
# Check awaited_by coroutine stacks (line numbers only)
id_to_task = self._get_task_id_map(stack_trace)
awaited_by_coroutine_stacks = {
task.task_name: sorted(
(
id_to_task[coro.task_name].task_name,
tuple(
self._frame_to_lineno_tuple(frame) for frame in coro.call_stack
),
)
for coro in task.awaited_by
)
for task in stack_trace[0].awaited_by
}
self.assertEqual(
awaited_by_coroutine_stacks,
{
"Task-1": [],
"Task-2": [
(
"Task-1",
(
(staggered.__file__, ANY, "staggered_race", None),
(script_name, 21, "main", None),
),
)
],
},
)
finally:
_cleanup_sockets(client_socket, server_socket)
@skip_if_not_supported
@unittest.skipIf(
sys.platform == "linux" and not PROCESS_VM_READV_SUPPORTED,
"Test only runs on Linux with process_vm_readv support",
)
def test_async_global_awaited_by(self):
# Reduced from 1000 to 100 to avoid file descriptor exhaustion
# when running tests in parallel (e.g., -j 20)
NUM_TASKS = 100
port = find_unused_port()
script = textwrap.dedent(
f"""\
import asyncio
import os
import random
import sys
import socket
from string import ascii_lowercase, digits
from test.support import socket_helper, SHORT_TIMEOUT
HOST = '127.0.0.1'
PORT = socket_helper.find_unused_port()
connections = 0
sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
sock.connect(('localhost', {port}))
class EchoServerProtocol(asyncio.Protocol):
def connection_made(self, transport):
global connections
connections += 1
self.transport = transport
def data_received(self, data):
self.transport.write(data)
self.transport.close()
async def echo_client(message):
reader, writer = await asyncio.open_connection(HOST, PORT)
writer.write(message.encode())
await writer.drain()
data = await reader.read(100)
assert message == data.decode()
writer.close()
await writer.wait_closed()
sock.sendall(b"ready")
await asyncio.sleep(SHORT_TIMEOUT)
async def echo_client_spam(server):
async with asyncio.TaskGroup() as tg:
while connections < {NUM_TASKS}:
msg = list(ascii_lowercase + digits)
random.shuffle(msg)
tg.create_task(echo_client("".join(msg)))
await asyncio.sleep(0)
server.close()
await server.wait_closed()
async def main():
loop = asyncio.get_running_loop()
server = await loop.create_server(EchoServerProtocol, HOST, PORT)
async with server:
async with asyncio.TaskGroup() as tg:
tg.create_task(server.serve_forever(), name="server task")
tg.create_task(echo_client_spam(server), name="echo client spam")
asyncio.run(main())
"""
)
with os_helper.temp_dir() as work_dir:
script_dir = os.path.join(work_dir, "script_pkg")
os.mkdir(script_dir)
server_socket = _create_server_socket(port)
script_name = _make_test_script(script_dir, "script", script)
client_socket = None
try:
with _managed_subprocess([sys.executable, script_name]) as p:
client_socket, _ = server_socket.accept()
server_socket.close()
server_socket = None
# Wait for NUM_TASKS "ready" signals
try:
_wait_for_n_signals(client_socket, b"ready", NUM_TASKS)
except RuntimeError as e:
self.fail(str(e))
all_awaited_by = get_all_awaited_by(p.pid)
# Expected: a list of two elements: 1 thread, 1 interp
self.assertEqual(len(all_awaited_by), 2)
# Expected: a tuple with the thread ID and the awaited_by list
self.assertEqual(len(all_awaited_by[0]), 2)
# Expected: no tasks in the fallback per-interp task list
self.assertEqual(all_awaited_by[1], (0, []))
entries = all_awaited_by[0][1]
# Expected: at least NUM_TASKS pending tasks
self.assertGreaterEqual(len(entries), NUM_TASKS)
# Check the main task structure
main_stack = [
FrameInfo(
[taskgroups.__file__, ANY, "TaskGroup._aexit", ANY]
),
FrameInfo(
[taskgroups.__file__, ANY, "TaskGroup.__aexit__", ANY]
),
FrameInfo([script_name, ANY, "main", ANY]),
]
self.assertIn(
TaskInfo(
[ANY, "Task-1", [CoroInfo([main_stack, ANY])], []]
),
entries,
)
self.assertIn(
TaskInfo(
[
ANY,
"server task",
[
CoroInfo(
[
[
FrameInfo(
[
base_events.__file__,
ANY,
"Server.serve_forever",
ANY,
]
)
],
ANY,
]
)
],
[
CoroInfo(
[
[
FrameInfo(
[
taskgroups.__file__,
ANY,
"TaskGroup._aexit",
ANY,
]
),
FrameInfo(
[
taskgroups.__file__,
ANY,
"TaskGroup.__aexit__",
ANY,
]
),
FrameInfo(
[script_name, ANY, "main", ANY]
),
],
ANY,
]
)
],
]
),
entries,
)
self.assertIn(
TaskInfo(
[
ANY,
"Task-4",
[
CoroInfo(
[
[
FrameInfo(
[
tasks.__file__,
ANY,
"sleep",
ANY,
]
),
FrameInfo(
[
script_name,
ANY,
"echo_client",
ANY,
]
),
],
ANY,
]
)
],
[
CoroInfo(
[
[
FrameInfo(
[
taskgroups.__file__,
ANY,
"TaskGroup._aexit",
ANY,
]
),
FrameInfo(
[
taskgroups.__file__,
ANY,
"TaskGroup.__aexit__",
ANY,
]
),
FrameInfo(
[
script_name,
ANY,
"echo_client_spam",
ANY,
]
),
],
ANY,
]
)
],
]
),
entries,
)
# Find tasks awaited by echo_client_spam via TaskGroup
def matches_awaited_by_pattern(task):
if len(task.awaited_by) != 1:
return False
coro = task.awaited_by[0]
if len(coro.call_stack) != 3:
return False
funcnames = [f.funcname for f in coro.call_stack]
return funcnames == [
"TaskGroup._aexit",
"TaskGroup.__aexit__",
"echo_client_spam",
]
tasks_with_awaited = [
task
for task in entries
if matches_awaited_by_pattern(task)
]
self.assertGreaterEqual(len(tasks_with_awaited), NUM_TASKS)
# Final task should be from echo client spam (not on Windows)
if sys.platform != "win32":
self.assertEqual(
tasks_with_awaited[-1].awaited_by,
entries[-1].awaited_by,
)
finally:
_cleanup_sockets(client_socket, server_socket)
@skip_if_not_supported
@unittest.skipIf(
sys.platform == "linux" and not PROCESS_VM_READV_SUPPORTED,
"Test only runs on Linux with process_vm_readv support",
)
def test_async_awaited_by_skips_set_tombstones(self):
script_body = """\
import asyncio
class RemovedTask(asyncio.Task):
def __hash__(self):
return 0
class RemainingTask(asyncio.Task):
def __hash__(self):
return 1
async def main():
victim = asyncio.current_task()
victim.set_name("victim")
removed = RemovedTask(
asyncio.sleep(10_000), name="removed"
)
remaining = RemainingTask(
asyncio.sleep(10_000), name="remaining"
)
asyncio.future_add_to_awaited_by(victim, removed)
asyncio.future_add_to_awaited_by(victim, remaining)
# Removing hash 0 leaves a dummy in slot 0 before the only
# active entry in slot 1. It must not count toward the set's
# used entries.
asyncio.future_discard_from_awaited_by(victim, removed)
sock.sendall(b"ready")
sock.recv(16)
asyncio.run(main())
"""
with self._target_process(script_body) as (
_,
client_socket,
make_unwinder,
):
_wait_for_signal(client_socket, b"ready")
for method_name in (
"get_async_stack_trace",
"get_all_awaited_by",
):
with self.subTest(method=method_name):
unwinder = make_unwinder(cache_frames=False)
stack_trace = getattr(unwinder, method_name)()
relationships = self._get_awaited_by_relationships(
stack_trace
)
self.assertEqual(
relationships["victim"],
{"remaining"},
)
client_socket.sendall(b"done")
@skip_if_not_supported
@unittest.skipIf(
sys.platform == "linux" and not PROCESS_VM_READV_SUPPORTED,
"Test only runs on Linux with process_vm_readv support",
)
def test_async_global_awaited_by_from_non_main_thread(self):
port = find_unused_port()
script = textwrap.dedent(
f"""\
import asyncio
import socket
import threading
import time
sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
sock.connect(('localhost', {port}))
async def worker_main():
task = asyncio.create_task(
asyncio.sleep(10_000),
name="worker task",
)
await asyncio.sleep(0)
sock.sendall(f"ready:{{threading.get_native_id()}}\\n".encode())
await task
def run_worker_loop():
asyncio.run(worker_main())
threading.Thread(
target=run_worker_loop,
name="async-worker",
daemon=True,
).start()
time.sleep(10_000)
"""
)
with os_helper.temp_dir() as work_dir:
script_dir = os.path.join(work_dir, "script_pkg")
os.mkdir(script_dir)
server_socket = _create_server_socket(port)
script_name = _make_test_script(script_dir, "script", script)
client_socket = None
try:
with _managed_subprocess([sys.executable, script_name]) as p:
client_socket, _ = server_socket.accept()
server_socket.close()
server_socket = None
response = _wait_for_signal(client_socket, b"ready:")
worker_thread_id = int(
response.split(b"ready:", 1)[1].splitlines()[0]
)
for _ in busy_retry(SHORT_TIMEOUT):
all_awaited_by = get_all_awaited_by(p.pid)
if any(
task.task_name == "worker task"
for info in all_awaited_by
if info.thread_id == worker_thread_id
for task in info.awaited_by
):
break
else:
self.fail(
"get_all_awaited_by() did not report "
"the asyncio task from the non-main thread"
)
finally:
_cleanup_sockets(client_socket, server_socket)
@skip_if_not_supported
@unittest.skipIf(
sys.platform == "linux" and not PROCESS_VM_READV_SUPPORTED,
"Test only runs on Linux with process_vm_readv support",
)
def test_async_remote_stack_trace_from_non_main_thread(self):
port = find_unused_port()
script = textwrap.dedent(
f"""\
import asyncio
import socket
import threading
import time
sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
sock.connect(('localhost', {port}))
def blocking_call():
sock.sendall(f"ready:{{threading.get_native_id()}}\\n".encode())
time.sleep(10_000)
async def worker_task():
await asyncio.sleep(0)
blocking_call()
async def worker_main():
task = asyncio.create_task(
worker_task(),
name="worker task",
)
await task
def run_worker_loop():
asyncio.run(worker_main())
threading.Thread(
target=run_worker_loop,
name="async-worker",
daemon=True,
).start()
time.sleep(10_000)
"""
)
with os_helper.temp_dir() as work_dir:
script_dir = os.path.join(work_dir, "script_pkg")
os.mkdir(script_dir)
server_socket = _create_server_socket(port)
script_name = _make_test_script(script_dir, "script", script)
client_socket = None
try:
with _managed_subprocess([sys.executable, script_name]) as p:
client_socket, _ = server_socket.accept()
server_socket.close()
server_socket = None
response = _wait_for_signal(client_socket, b"ready:")
worker_thread_id = int(
response.split(b"ready:", 1)[1].splitlines()[0]
)
for _ in busy_retry(SHORT_TIMEOUT):
stack_trace = get_async_stack_trace(p.pid)
if any(
task.task_name == "worker task"
for info in stack_trace
if info.thread_id == worker_thread_id
for task in info.awaited_by
):
break
else:
self.fail(
"get_async_stack_trace() did not report "
"the running asyncio task from the non-main thread"
)
finally:
_cleanup_sockets(client_socket, server_socket)
@skip_if_not_supported
@unittest.skipIf(
sys.platform == "linux" and not PROCESS_VM_READV_SUPPORTED,
"Test only runs on Linux with process_vm_readv support",
)
def test_self_trace(self):
stack_trace = get_stack_trace(os.getpid())
this_thread_stack = None
for interpreter_info in stack_trace:
for thread_info in interpreter_info.threads:
if thread_info.thread_id == threading.get_native_id():
this_thread_stack = thread_info.frame_info
break
if this_thread_stack:
break
self.assertIsNotNone(this_thread_stack)
# Check the top two frames
self.assertGreaterEqual(len(this_thread_stack), 2)
self.assertEqual(this_thread_stack[0].funcname, "get_stack_trace")
self.assertTrue(this_thread_stack[0].filename.endswith("test_external_inspection.py"))
self.assertEqual(this_thread_stack[1].funcname, "TestGetStackTrace.test_self_trace")
self.assertTrue(this_thread_stack[1].filename.endswith("test_external_inspection.py"))
@skip_if_not_supported
@unittest.skipIf(
sys.platform == "linux" and not PROCESS_VM_READV_SUPPORTED,
"Test only runs on Linux with process_vm_readv support",
)
def test_empty_native_thread_stack(self):
_testcapi = import_module("_testcapi")
lock = threading.Lock()
lock.acquire()
# A built-in callback leaves the C thread's Python stack empty.
_testcapi.call_in_temporary_c_thread(lock.acquire, False)
try:
for cache_frames, native in ((False, False), (False, True),
(True, False), (True, True)):
with self.subTest(cache_frames=cache_frames, native=native):
unwinder = RemoteUnwinder(
os.getpid(), all_threads=True, cache_frames=cache_frames,
native=native,
)
_get_stack_trace_with_retry(
unwinder, condition=lambda trace: len(trace[0].threads) == 2,
)
threads = unwinder.get_stack_trace()[0].threads
native_stack, python_stack = sorted(
(thread.frame_info for thread in threads), key=len,
)
self.assertEqual(native_stack, [])
self.assertEqual(
python_stack[0].funcname,
"TestGetStackTrace.test_empty_native_thread_stack",
)
finally:
lock.release()
_testcapi.join_temporary_c_thread()
@skip_if_not_supported
@unittest.skipIf(
sys.platform == "linux" and not PROCESS_VM_READV_SUPPORTED,
"Test only runs on Linux with process_vm_readv support",
)
def test_popping_python_frame_is_not_native(self):
script = """\
def leaf(depth):
if depth:
leaf(depth - 1)
while True:
leaf(300)
"""
with _managed_subprocess([sys.executable, "-c", script]) as process:
for _ in busy_retry(SHORT_TIMEOUT):
try:
unwinder = RemoteUnwinder(
process.pid, native=True, gc=False, cache_frames=False,
)
except RuntimeError:
continue
break
samples = 0
for _ in range(10_000):
try:
threads = unwinder.get_stack_trace()[0].threads
except TRANSIENT_ERRORS:
continue
if not threads:
continue
frames = threads[0].frame_info
names = [frame.funcname for frame in frames]
if "leaf" not in names:
continue
samples += 1
self.assertNotIn(("leaf", "<native>"), zip(names, names[1:]))
self.assertGreater(samples, 1000)
@skip_if_not_supported
@unittest.skipIf(
sys.platform == "linux" and not PROCESS_VM_READV_SUPPORTED,
"Test only runs on Linux with process_vm_readv support",
)
@requires_subinterpreters
def test_subinterpreter_stack_trace(self):
port = find_unused_port()
import pickle
subinterp_code = textwrap.dedent(f"""
import socket
import time
def sub_worker():
def nested_func():
sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
sock.connect(('localhost', {port}))
sock.sendall(b"ready:sub\\n")
time.sleep(10_000)
nested_func()
sub_worker()
""").strip()
pickled_code = pickle.dumps(subinterp_code)
script = textwrap.dedent(
f"""
from concurrent import interpreters
import time
import sys
import socket
import threading
sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
sock.connect(('localhost', {port}))
def main_worker():
sock.sendall(b"ready:main\\n")
time.sleep(10_000)
def run_subinterp():
subinterp = interpreters.create()
import pickle
pickled_code = {pickled_code!r}
subinterp_code = pickle.loads(pickled_code)
subinterp.exec(subinterp_code)
sub_thread = threading.Thread(target=run_subinterp)
sub_thread.start()
main_thread = threading.Thread(target=main_worker)
main_thread.start()
main_thread.join()
sub_thread.join()
"""
)
with os_helper.temp_dir() as work_dir:
script_dir = os.path.join(work_dir, "script_pkg")
os.mkdir(script_dir)
server_socket = _create_server_socket(port)
script_name = _make_test_script(script_dir, "script", script)
client_sockets = []
try:
with _managed_subprocess([sys.executable, script_name]) as p:
# Accept connections from both main and subinterpreter
responses = set()
while len(responses) < 2:
try:
client_socket, _ = server_socket.accept()
client_sockets.append(client_socket)
response = client_socket.recv(1024)
if b"ready:main" in response:
responses.add("main")
if b"ready:sub" in response:
responses.add("sub")
except socket.timeout:
break
server_socket.close()
server_socket = None
stack_trace = get_stack_trace(p.pid)
# Verify we have at least one interpreter
self.assertGreaterEqual(len(stack_trace), 1)
# Look for main interpreter (ID 0) and subinterpreter (ID > 0)
main_interp = None
sub_interp = None
for interpreter_info in stack_trace:
if interpreter_info.interpreter_id == 0:
main_interp = interpreter_info
elif interpreter_info.interpreter_id > 0:
sub_interp = interpreter_info
self.assertIsNotNone(
main_interp, "Main interpreter should be present"
)
# Check main interpreter has expected stack trace
main_found = self._find_frame_in_trace(
[main_interp], lambda f: f.funcname == "main_worker"
)
self.assertIsNotNone(
main_found,
"Main interpreter should have main_worker in stack",
)
# If subinterpreter is present, check its stack trace
if sub_interp:
sub_found = self._find_frame_in_trace(
[sub_interp],
lambda f: f.funcname
in ("sub_worker", "nested_func"),
)
self.assertIsNotNone(
sub_found,
"Subinterpreter should have sub_worker or nested_func in stack",
)
finally:
_cleanup_sockets(*client_sockets, server_socket)
@skip_if_not_supported
@unittest.skipIf(
sys.platform == "linux" and not PROCESS_VM_READV_SUPPORTED,
"Test only runs on Linux with process_vm_readv support",
)
@requires_subinterpreters
def test_multiple_subinterpreters_with_threads(self):
port = find_unused_port()
import pickle
subinterp1_code = textwrap.dedent(f"""
import socket
import time
import threading
def worker1():
def nested_func():
sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
sock.connect(('localhost', {port}))
sock.sendall(b"ready:sub1-t1\\n")
time.sleep(10_000)
nested_func()
def worker2():
def nested_func():
sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
sock.connect(('localhost', {port}))
sock.sendall(b"ready:sub1-t2\\n")
time.sleep(10_000)
nested_func()
t1 = threading.Thread(target=worker1)
t2 = threading.Thread(target=worker2)
t1.start()
t2.start()
t1.join()
t2.join()
""").strip()
subinterp2_code = textwrap.dedent(f"""
import socket
import time
import threading
def worker1():
def nested_func():
sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
sock.connect(('localhost', {port}))
sock.sendall(b"ready:sub2-t1\\n")
time.sleep(10_000)
nested_func()
def worker2():
def nested_func():
sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
sock.connect(('localhost', {port}))
sock.sendall(b"ready:sub2-t2\\n")
time.sleep(10_000)
nested_func()
t1 = threading.Thread(target=worker1)
t2 = threading.Thread(target=worker2)
t1.start()
t2.start()
t1.join()
t2.join()
""").strip()
pickled_code1 = pickle.dumps(subinterp1_code)
pickled_code2 = pickle.dumps(subinterp2_code)
script = textwrap.dedent(
f"""
from concurrent import interpreters
import time
import sys
import socket
import threading
sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
sock.connect(('localhost', {port}))
def main_worker():
sock.sendall(b"ready:main\\n")
time.sleep(10_000)
def run_subinterp1():
subinterp = interpreters.create()
import pickle
pickled_code = {pickled_code1!r}
subinterp_code = pickle.loads(pickled_code)
subinterp.exec(subinterp_code)
def run_subinterp2():
subinterp = interpreters.create()
import pickle
pickled_code = {pickled_code2!r}
subinterp_code = pickle.loads(pickled_code)
subinterp.exec(subinterp_code)
sub1_thread = threading.Thread(target=run_subinterp1)
sub2_thread = threading.Thread(target=run_subinterp2)
sub1_thread.start()
sub2_thread.start()
main_thread = threading.Thread(target=main_worker)
main_thread.start()
main_thread.join()
sub1_thread.join()
sub2_thread.join()
"""
)
with os_helper.temp_dir() as work_dir:
script_dir = os.path.join(work_dir, "script_pkg")
os.mkdir(script_dir)
server_socket = _create_server_socket(port, backlog=5)
script_name = _make_test_script(script_dir, "script", script)
client_sockets = []
try:
with _managed_subprocess([sys.executable, script_name]) as p:
# Accept connections from main and all subinterpreter threads
expected_responses = {
"ready:main",
"ready:sub1-t1",
"ready:sub1-t2",
"ready:sub2-t1",
"ready:sub2-t2",
}
responses = set()
while len(responses) < 5:
try:
client_socket, _ = server_socket.accept()
client_sockets.append(client_socket)
response = client_socket.recv(1024)
response_str = response.decode().strip()
if response_str in expected_responses:
responses.add(response_str)
except socket.timeout:
break
server_socket.close()
server_socket = None
stack_trace = get_stack_trace(p.pid)
# Verify we have multiple interpreters
self.assertGreaterEqual(len(stack_trace), 2)
# Count interpreters by ID
interpreter_ids = {
interp.interpreter_id for interp in stack_trace
}
self.assertIn(
0,
interpreter_ids,
"Main interpreter should be present",
)
self.assertGreaterEqual(len(interpreter_ids), 3)
# Count total threads
total_threads = sum(
len(interp.threads) for interp in stack_trace
)
self.assertGreaterEqual(total_threads, 5)
# Look for expected function names
all_funcnames = set()
for interpreter_info in stack_trace:
for thread_info in interpreter_info.threads:
for frame in thread_info.frame_info:
all_funcnames.add(frame.funcname)
expected_funcs = {
"main_worker",
"worker1",
"worker2",
"nested_func",
}
found_funcs = expected_funcs.intersection(all_funcnames)
self.assertGreater(len(found_funcs), 0)
finally:
_cleanup_sockets(*client_sockets, server_socket)
@skip_if_not_supported
@unittest.skipIf(
sys.platform == "linux" and not PROCESS_VM_READV_SUPPORTED,
"Test only runs on Linux with process_vm_readv support",
)
@requires_gil_enabled("Free threaded builds don't have an 'active thread'")
def test_only_active_thread(self):
port = find_unused_port()
script = textwrap.dedent(
f"""\
import time, sys, socket, threading
sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
sock.connect(('localhost', {port}))
def worker_thread(name, barrier, ready_event):
barrier.wait()
ready_event.wait()
time.sleep(10_000)
def main_work():
sock.sendall(b"working\\n")
count = 0
while count < 100000000:
count += 1
if count % 10000000 == 0:
pass
sock.sendall(b"done\\n")
num_threads = 3
barrier = threading.Barrier(num_threads + 1)
ready_event = threading.Event()
threads = []
for i in range(num_threads):
t = threading.Thread(target=worker_thread, args=(f"Worker-{{i}}", barrier, ready_event))
t.start()
threads.append(t)
barrier.wait()
sock.sendall(b"ready\\n")
ready_event.set()
main_work()
"""
)
with os_helper.temp_dir() as work_dir:
script_dir = os.path.join(work_dir, "script_pkg")
os.mkdir(script_dir)
server_socket = _create_server_socket(port)
script_name = _make_test_script(script_dir, "script", script)
client_socket = None
try:
with _managed_subprocess([sys.executable, script_name]) as p:
client_socket, _ = server_socket.accept()
server_socket.close()
server_socket = None
# Wait for ready and working signals
_wait_for_signal(client_socket, [b"ready", b"working"])
# Get stack trace with all threads
unwinder_all = RemoteUnwinder(p.pid, all_threads=True)
for _ in busy_retry(SHORT_TIMEOUT):
with contextlib.suppress(*TRANSIENT_ERRORS):
all_traces = unwinder_all.get_stack_trace()
found = self._find_frame_in_trace(
all_traces,
lambda f: f.funcname == "main_work"
and f.location.lineno > 12,
)
if found:
break
else:
self.fail(
"Main thread did not start its busy work on time"
)
# Get stack trace with only GIL holder
unwinder_gil = RemoteUnwinder(
p.pid, only_active_thread=True
)
# Use condition to retry until we capture a thread holding the GIL
# (sampling may catch moments with no GIL holder on slow CI)
gil_traces = _get_stack_trace_with_retry(
unwinder_gil,
condition=lambda t: sum(len(i.threads) for i in t) >= 1,
)
# Count threads
total_threads = sum(
len(interp.threads) for interp in all_traces
)
self.assertGreater(total_threads, 1)
total_gil_threads = sum(
len(interp.threads) for interp in gil_traces
)
self.assertEqual(total_gil_threads, 1)
# Get the GIL holder thread ID
gil_thread_id = None
for interpreter_info in gil_traces:
if interpreter_info.threads:
gil_thread_id = interpreter_info.threads[
0
].thread_id
break
# Get all thread IDs
all_thread_ids = []
for interpreter_info in all_traces:
for thread_info in interpreter_info.threads:
all_thread_ids.append(thread_info.thread_id)
self.assertIn(gil_thread_id, all_thread_ids)
finally:
_cleanup_sockets(client_socket, server_socket)
@skip_if_not_supported
@unittest.skipIf(
sys.platform == "linux" and not PROCESS_VM_READV_SUPPORTED,
"Test only runs on Linux with process_vm_readv support",
)
def test_opcodes_collection(self):
"""Test that opcodes are collected when the opcodes flag is set."""
script = textwrap.dedent(
"""\
import time, sys, socket
sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
sock.connect(('localhost', {port}))
def foo():
sock.sendall(b"ready")
time.sleep(10_000)
foo()
"""
)
def get_trace_with_opcodes(pid):
return RemoteUnwinder(pid, opcodes=True).get_stack_trace()
stack_trace, _ = self._run_script_and_get_trace(
script, get_trace_with_opcodes, wait_for_signals=b"ready"
)
# Find our foo frame and verify it has an opcode
foo_frame = self._find_frame_in_trace(
stack_trace, lambda f: f.funcname == "foo"
)
self.assertIsNotNone(foo_frame, "Could not find foo frame")
self.assertIsInstance(foo_frame.opcode, int)
self.assertGreaterEqual(foo_frame.opcode, 0)
@skip_if_not_supported
@unittest.skipIf(
sys.platform == "linux" and not PROCESS_VM_READV_SUPPORTED,
"Test only runs on Linux with process_vm_readv support",
)
def test_location_tuple_format(self):
"""Test that location is a 4-tuple (lineno, end_lineno, col_offset, end_col_offset)."""
script = textwrap.dedent(
"""\
import time, sys, socket
sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
sock.connect(('localhost', {port}))
def foo():
sock.sendall(b"ready")
time.sleep(10_000)
foo()
"""
)
def get_trace_with_opcodes(pid):
return RemoteUnwinder(pid, opcodes=True).get_stack_trace()
stack_trace, _ = self._run_script_and_get_trace(
script, get_trace_with_opcodes, wait_for_signals=b"ready"
)
# Find our foo frame
foo_frame = self._find_frame_in_trace(
stack_trace, lambda f: f.funcname == "foo"
)
self.assertIsNotNone(foo_frame, "Could not find foo frame")
# Check location is a 4-tuple with valid values
location = foo_frame.location
self.assertIsInstance(location, tuple)
self.assertEqual(len(location), 4)
lineno, end_lineno, col_offset, end_col_offset = location
self.assertIsInstance(lineno, int)
self.assertGreater(lineno, 0)
self.assertIsInstance(end_lineno, int)
self.assertGreaterEqual(end_lineno, lineno)
self.assertIsInstance(col_offset, int)
self.assertGreaterEqual(col_offset, 0)
self.assertIsInstance(end_col_offset, int)
self.assertGreaterEqual(end_col_offset, col_offset)
@skip_if_not_supported
@unittest.skipIf(
sys.platform == "linux" and not PROCESS_VM_READV_SUPPORTED,
"Test only runs on Linux with process_vm_readv support",
)
def test_location_tuple_exact_values(self):
"""Test exact values of location tuple including column offsets."""
script = textwrap.dedent(
"""\
import time, sys, socket
sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
sock.connect(('localhost', {port}))
def foo():
sock.sendall(b"ready")
time.sleep(10_000)
foo()
"""
)
def get_trace_with_opcodes(pid):
return RemoteUnwinder(pid, opcodes=True).get_stack_trace()
stack_trace, _ = self._run_script_and_get_trace(
script, get_trace_with_opcodes, wait_for_signals=b"ready"
)
foo_frame = self._find_frame_in_trace(
stack_trace, lambda f: f.funcname == "foo"
)
self.assertIsNotNone(foo_frame, "Could not find foo frame")
# Can catch either sock.sendall (line 7) or time.sleep (line 8)
location = foo_frame.location
valid_locations = [
(7, 7, 4, 26), # sock.sendall(b"ready")
(8, 8, 4, 22), # time.sleep(10_000)
]
actual = (location.lineno, location.end_lineno,
location.col_offset, location.end_col_offset)
self.assertIn(actual, valid_locations)
@skip_if_not_supported
@unittest.skipIf(sys._is_gil_enabled(), "Requires free-threading")
@unittest.skipIf(
sys.platform == "linux" and not PROCESS_VM_READV_SUPPORTED,
"Requires process_vm_readv",
)
def test_tlbc_cache_refresh_after_growth(self):
# Reproducer from gh-157660.
script = textwrap.dedent("""\
import os, threading
from _remote_debugging import RemoteUnwinder
from _queue import SimpleQueue
from test import support
go = threading.Lock()
stop = threading.Lock()
go.acquire()
stop.acquire()
ready = SimpleQueue()
def leaf():
ready.put(None)
stop.acquire()
def start_leaf():
ready.put(None)
go.acquire()
leaf()
def park():
ready.put(None)
stop.acquire()
def leaf_count(u):
return sum(
f.funcname == "leaf"
for i in u.get_stack_trace()
for t in i.threads for f in t.frame_info
)
# SimpleQueue.put() and Lock.acquire() do not push Python frames.
# Once notified, the worker's stack stays stable until go is released.
threading.Thread(target=leaf, daemon=True).start()
ready.get(timeout=support.SHORT_TIMEOUT)
for _ in range(16):
threading.Thread(target=park, daemon=True).start()
ready.get(timeout=support.SHORT_TIMEOUT)
threading.Thread(target=start_leaf, daemon=True).start()
ready.get(timeout=support.SHORT_TIMEOUT)
u = RemoteUnwinder(os.getpid(), all_threads=True, cache_frames=False)
assert leaf_count(u) == 1
go.release()
ready.get(timeout=support.SHORT_TIMEOUT)
assert leaf_count(u) == 2
""")
result = subprocess.run(
[sys.executable, "-X", "gil=0", "-X", "tlbc=1", "-c", script],
capture_output=True,
text=True,
timeout=SHORT_TIMEOUT,
)
self.assertEqual(
result.returncode, 0,
f"stdout: {result.stdout}\nstderr: {result.stderr}",
)
@skip_if_not_supported
@unittest.skipIf(sys._is_gil_enabled(), "Requires free-threading")
@unittest.skipIf(
sys.platform == "linux" and not PROCESS_VM_READV_SUPPORTED,
"Requires process_vm_readv",
)
def test_tlbc_cache_refresh_after_slot_fill(self):
# Reproducer from gh-157660.
script = textwrap.dedent("""\
import os, threading
from _remote_debugging import RemoteUnwinder
from _queue import SimpleQueue
go = threading.Lock()
stop = threading.Lock()
go.acquire()
stop.acquire()
ready = SimpleQueue()
def leaf():
ready.put(None)
stop.acquire()
def start_leaf():
ready.put(None)
go.acquire()
leaf()
from test import support
def lines(u):
return sorted(
f.location.lineno
for i in u.get_stack_trace()
for t in i.threads for f in t.frame_info
if f.funcname == "leaf"
)
# SimpleQueue.put() and Lock.acquire() do not push Python frames.
# Once notified, the worker's stack stays stable until go is released.
threading.Thread(target=leaf, daemon=True).start()
ready.get(timeout=support.SHORT_TIMEOUT)
threading.Thread(target=start_leaf, daemon=True).start()
ready.get(timeout=support.SHORT_TIMEOUT)
u = RemoteUnwinder(os.getpid(), all_threads=True, cache_frames=False)
before = lines(u)
# The notification can be observed before put() returns, so either
# line in leaf() is a valid sample.
assert before in ([12], [13]), before
go.release()
ready.get(timeout=support.SHORT_TIMEOUT)
cached = lines(u)
assert len(cached) == 2, cached
assert all(line in (12, 13) for line in cached), cached
""")
result = subprocess.run(
[sys.executable, "-X", "gil=0", "-X", "tlbc=1", "-c", script],
capture_output=True,
text=True,
timeout=SHORT_TIMEOUT,
)
self.assertEqual(
result.returncode, 0,
f"stdout: {result.stdout}\nstderr: {result.stderr}",
)
class TestUnsupportedPlatformHandling(unittest.TestCase):
@unittest.skipIf(
sys.platform in ("linux", "darwin", "win32"),
"Test only runs on unsupported platforms (not Linux, macOS, or Windows)",
)
@unittest.skipIf(
sys.platform == "android", "Android raises Linux-specific exception"
)
def test_unsupported_platform_error(self):
with self.assertRaises(RuntimeError) as cm:
RemoteUnwinder(os.getpid())
self.assertIn(
"Reading the PyRuntime section is not supported on this platform",
str(cm.exception),
)
@requires_remote_subprocess_debugging()
class TestDetectionOfThreadStatus(RemoteInspectionTestBase):
def _run_thread_status_test(self, mode, check_condition):
"""
Common pattern for thread status detection tests.
Args:
mode: Profiling mode (PROFILING_MODE_CPU, PROFILING_MODE_GIL, etc.)
check_condition: Function(statuses, sleeper_tid, busy_tid) -> bool
"""
port = find_unused_port()
script = textwrap.dedent(
f"""\
import time, sys, socket, threading
import os
sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
sock.connect(('localhost', {port}))
def sleeper():
tid = threading.get_native_id()
sock.sendall(f'ready:sleeper:{{tid}}\\n'.encode())
time.sleep(10000)
def busy():
tid = threading.get_native_id()
sock.sendall(f'ready:busy:{{tid}}\\n'.encode())
x = 0
while True:
x = x + 1
time.sleep(0.5)
t1 = threading.Thread(target=sleeper)
t2 = threading.Thread(target=busy)
t1.start()
t2.start()
sock.sendall(b'ready:main\\n')
t1.join()
t2.join()
sock.close()
"""
)
with os_helper.temp_dir() as work_dir:
script_dir = os.path.join(work_dir, "script_pkg")
os.mkdir(script_dir)
server_socket = _create_server_socket(port)
script_name = _make_test_script(
script_dir, "thread_status_script", script
)
client_socket = None
try:
with _managed_subprocess([sys.executable, script_name]) as p:
client_socket, _ = server_socket.accept()
server_socket.close()
server_socket = None
# Wait for all ready signals and parse TIDs
response = _wait_for_signal(
client_socket,
[b"ready:main", b"ready:sleeper", b"ready:busy"],
)
sleeper_tid = None
busy_tid = None
for line in response.split(b"\n"):
if line.startswith(b"ready:sleeper:"):
try:
sleeper_tid = int(line.split(b":")[-1])
except (ValueError, IndexError):
pass
elif line.startswith(b"ready:busy:"):
try:
busy_tid = int(line.split(b":")[-1])
except (ValueError, IndexError):
pass
self.assertIsNotNone(
sleeper_tid, "Sleeper thread id not received"
)
self.assertIsNotNone(
busy_tid, "Busy thread id not received"
)
# Sample until we see expected thread states
statuses = {}
unwinder = RemoteUnwinder(
p.pid,
all_threads=True,
mode=mode,
skip_non_matching_threads=False,
)
for _ in busy_retry(SHORT_TIMEOUT):
with contextlib.suppress(*TRANSIENT_ERRORS):
traces = unwinder.get_stack_trace()
statuses = self._get_thread_statuses(traces)
if check_condition(
statuses, sleeper_tid, busy_tid
):
break
return statuses, sleeper_tid, busy_tid
finally:
_cleanup_sockets(client_socket, server_socket)
@unittest.skipIf(
sys.platform not in ("linux", "darwin", "win32"),
"Test only runs on supported platforms (Linux, macOS, or Windows)",
)
@unittest.skipIf(
sys.platform == "android", "Android raises Linux-specific exception"
)
def test_thread_status_detection(self):
def check_cpu_status(statuses, sleeper_tid, busy_tid):
return (
sleeper_tid in statuses
and busy_tid in statuses
and not (statuses[sleeper_tid] & THREAD_STATUS_ON_CPU)
and (statuses[busy_tid] & THREAD_STATUS_ON_CPU)
)
statuses, sleeper_tid, busy_tid = self._run_thread_status_test(
PROFILING_MODE_CPU, check_cpu_status
)
self.assertIn(sleeper_tid, statuses)
self.assertIn(busy_tid, statuses)
self.assertFalse(
statuses[sleeper_tid] & THREAD_STATUS_ON_CPU,
"Sleeper thread should be off CPU",
)
self.assertTrue(
statuses[busy_tid] & THREAD_STATUS_ON_CPU,
"Busy thread should be on CPU",
)
@unittest.skipIf(
sys.platform not in ("linux", "darwin", "win32"),
"Test only runs on supported platforms (Linux, macOS, or Windows)",
)
@unittest.skipIf(
sys.platform == "android", "Android raises Linux-specific exception"
)
def test_thread_status_gil_detection(self):
def check_gil_status(statuses, sleeper_tid, busy_tid):
return (
sleeper_tid in statuses
and busy_tid in statuses
and not (statuses[sleeper_tid] & THREAD_STATUS_HAS_GIL)
and (statuses[busy_tid] & THREAD_STATUS_HAS_GIL)
)
statuses, sleeper_tid, busy_tid = self._run_thread_status_test(
PROFILING_MODE_GIL, check_gil_status
)
self.assertIn(sleeper_tid, statuses)
self.assertIn(busy_tid, statuses)
self.assertFalse(
statuses[sleeper_tid] & THREAD_STATUS_HAS_GIL,
"Sleeper thread should not have GIL",
)
self.assertTrue(
statuses[busy_tid] & THREAD_STATUS_HAS_GIL,
"Busy thread should have GIL",
)
@unittest.skipIf(
sys.platform not in ("linux", "darwin", "win32"),
"Test only runs on supported platforms (Linux, macOS, or Windows)",
)
@unittest.skipIf(
sys.platform == "android", "Android raises Linux-specific exception"
)
def test_thread_status_all_mode_detection(self):
port = find_unused_port()
script = textwrap.dedent(
f"""\
import socket
import threading
import time
import sys
def sleeper_thread():
conn = socket.create_connection(("localhost", {port}))
conn.sendall(b"sleeper:" + str(threading.get_native_id()).encode())
while True:
time.sleep(1)
def busy_thread():
conn = socket.create_connection(("localhost", {port}))
conn.sendall(b"busy:" + str(threading.get_native_id()).encode())
while True:
sum(range(100000))
t1 = threading.Thread(target=sleeper_thread)
t2 = threading.Thread(target=busy_thread)
t1.start()
t2.start()
t1.join()
t2.join()
"""
)
with os_helper.temp_dir() as tmp_dir:
script_file = make_script(tmp_dir, "script", script)
server_socket = _create_server_socket(port, backlog=2)
client_sockets = []
try:
with _managed_subprocess(
[sys.executable, script_file],
) as p:
sleeper_tid = None
busy_tid = None
# Receive thread IDs from the child process
for _ in range(2):
client_socket, _ = server_socket.accept()
client_sockets.append(client_socket)
line = client_socket.recv(1024)
if line:
if line.startswith(b"sleeper:"):
try:
sleeper_tid = int(line.split(b":")[-1])
except (ValueError, IndexError):
pass
elif line.startswith(b"busy:"):
try:
busy_tid = int(line.split(b":")[-1])
except (ValueError, IndexError):
pass
server_socket.close()
server_socket = None
statuses = {}
unwinder = RemoteUnwinder(
p.pid,
all_threads=True,
mode=PROFILING_MODE_ALL,
skip_non_matching_threads=False,
)
for _ in busy_retry(SHORT_TIMEOUT):
with contextlib.suppress(*TRANSIENT_ERRORS):
traces = unwinder.get_stack_trace()
statuses = self._get_thread_statuses(traces)
# Check ALL mode provides both GIL and CPU info
if (
sleeper_tid in statuses
and busy_tid in statuses
and not (
statuses[sleeper_tid]
& THREAD_STATUS_ON_CPU
)
and not (
statuses[sleeper_tid]
& THREAD_STATUS_HAS_GIL
)
and (statuses[busy_tid] & THREAD_STATUS_ON_CPU)
and (
statuses[busy_tid] & THREAD_STATUS_HAS_GIL
)
):
break
self.assertIsNotNone(
sleeper_tid, "Sleeper thread id not received"
)
self.assertIsNotNone(
busy_tid, "Busy thread id not received"
)
self.assertIn(sleeper_tid, statuses)
self.assertIn(busy_tid, statuses)
# Sleeper: off CPU, no GIL
self.assertFalse(
statuses[sleeper_tid] & THREAD_STATUS_ON_CPU,
"Sleeper should be off CPU",
)
self.assertFalse(
statuses[sleeper_tid] & THREAD_STATUS_HAS_GIL,
"Sleeper should not have GIL",
)
# Busy: on CPU, has GIL
self.assertTrue(
statuses[busy_tid] & THREAD_STATUS_ON_CPU,
"Busy should be on CPU",
)
self.assertTrue(
statuses[busy_tid] & THREAD_STATUS_HAS_GIL,
"Busy should have GIL",
)
finally:
_cleanup_sockets(*client_sockets, server_socket)
def _make_exception_test_script(self, port):
"""Create script with exception and normal threads for testing."""
return textwrap.dedent(
f"""\
import socket
import threading
import time
def exception_thread():
conn = socket.create_connection(("localhost", {port}))
conn.sendall(b"exception:" + str(threading.get_native_id()).encode())
try:
raise ValueError("test exception")
except ValueError:
while True:
time.sleep(0.01)
def normal_thread():
conn = socket.create_connection(("localhost", {port}))
conn.sendall(b"normal:" + str(threading.get_native_id()).encode())
while True:
sum(range(1000))
t1 = threading.Thread(target=exception_thread)
t2 = threading.Thread(target=normal_thread)
t1.start()
t2.start()
t1.join()
t2.join()
"""
)
@contextmanager
def _run_exception_test_process(self):
"""Context manager to run exception test script and yield thread IDs and process."""
port = find_unused_port()
script = self._make_exception_test_script(port)
with os_helper.temp_dir() as tmp_dir:
script_file = make_script(tmp_dir, "script", script)
server_socket = _create_server_socket(port, backlog=2)
client_sockets = []
try:
with _managed_subprocess([sys.executable, script_file]) as p:
exception_tid = None
normal_tid = None
for _ in range(2):
client_socket, _ = server_socket.accept()
client_sockets.append(client_socket)
line = client_socket.recv(1024)
if line:
if line.startswith(b"exception:"):
try:
exception_tid = int(line.split(b":")[-1])
except (ValueError, IndexError):
pass
elif line.startswith(b"normal:"):
try:
normal_tid = int(line.split(b":")[-1])
except (ValueError, IndexError):
pass
server_socket.close()
server_socket = None
yield p, exception_tid, normal_tid
finally:
_cleanup_sockets(*client_sockets, server_socket)
@unittest.skipIf(
sys.platform not in ("linux", "darwin", "win32"),
"Test only runs on supported platforms (Linux, macOS, or Windows)",
)
@unittest.skipIf(
sys.platform == "android", "Android raises Linux-specific exception"
)
def test_thread_status_exception_detection(self):
"""Test that THREAD_STATUS_HAS_EXCEPTION is set when thread has an active exception."""
with self._run_exception_test_process() as (p, exception_tid, normal_tid):
self.assertIsNotNone(exception_tid, "Exception thread id not received")
self.assertIsNotNone(normal_tid, "Normal thread id not received")
statuses = {}
unwinder = RemoteUnwinder(
p.pid,
all_threads=True,
mode=PROFILING_MODE_ALL,
skip_non_matching_threads=False,
)
for _ in busy_retry(SHORT_TIMEOUT):
with contextlib.suppress(*TRANSIENT_ERRORS):
traces = unwinder.get_stack_trace()
statuses = self._get_thread_statuses(traces)
if (
exception_tid in statuses
and normal_tid in statuses
and (statuses[exception_tid] & THREAD_STATUS_HAS_EXCEPTION)
and not (statuses[normal_tid] & THREAD_STATUS_HAS_EXCEPTION)
):
break
self.assertIn(exception_tid, statuses)
self.assertIn(normal_tid, statuses)
self.assertTrue(
statuses[exception_tid] & THREAD_STATUS_HAS_EXCEPTION,
"Exception thread should have HAS_EXCEPTION flag",
)
self.assertFalse(
statuses[normal_tid] & THREAD_STATUS_HAS_EXCEPTION,
"Normal thread should not have HAS_EXCEPTION flag",
)
@unittest.skipIf(
sys.platform not in ("linux", "darwin", "win32"),
"Test only runs on supported platforms (Linux, macOS, or Windows)",
)
@unittest.skipIf(
sys.platform == "android", "Android raises Linux-specific exception"
)
def test_thread_status_exception_mode_filtering(self):
"""Test that PROFILING_MODE_EXCEPTION correctly filters threads."""
with self._run_exception_test_process() as (p, exception_tid, normal_tid):
self.assertIsNotNone(exception_tid, "Exception thread id not received")
self.assertIsNotNone(normal_tid, "Normal thread id not received")
unwinder = RemoteUnwinder(
p.pid,
all_threads=True,
mode=PROFILING_MODE_EXCEPTION,
skip_non_matching_threads=True,
)
for _ in busy_retry(SHORT_TIMEOUT):
with contextlib.suppress(*TRANSIENT_ERRORS):
traces = unwinder.get_stack_trace()
statuses = self._get_thread_statuses(traces)
if exception_tid in statuses:
self.assertNotIn(
normal_tid,
statuses,
"Normal thread should be filtered out in exception mode",
)
return
self.fail("Never found exception thread in exception mode")
@requires_remote_subprocess_debugging()
class TestExceptionDetectionScenarios(RemoteInspectionTestBase):
"""Test exception detection across all scenarios.
This class verifies the exact conditions under which THREAD_STATUS_HAS_EXCEPTION
is set. Each test covers a specific scenario:
1. except_block: Thread inside except block
-> SHOULD have HAS_EXCEPTION (exc_info->exc_value is set)
2. finally_propagating: Exception propagating through finally block
-> SHOULD have HAS_EXCEPTION (current_exception is set)
3. finally_after_except: Finally block after except handled exception
-> Should NOT have HAS_EXCEPTION (exc_info cleared after except)
4. finally_no_exception: Finally block with no exception raised
-> Should NOT have HAS_EXCEPTION (no exception state)
"""
def _make_single_scenario_script(self, port, scenario):
"""Create script for a single exception scenario."""
scenarios = {
"except_block": f"""\
import socket
import threading
import time
def target_thread():
'''Inside except block - exception info is present'''
conn = socket.create_connection(("localhost", {port}))
conn.sendall(b"ready:" + str(threading.get_native_id()).encode())
try:
raise ValueError("test")
except ValueError:
while True:
time.sleep(0.01)
t = threading.Thread(target=target_thread)
t.start()
t.join()
""",
"finally_propagating": f"""\
import socket
import threading
import time
def target_thread():
'''Exception propagating through finally - current_exception is set'''
conn = socket.create_connection(("localhost", {port}))
conn.sendall(b"ready:" + str(threading.get_native_id()).encode())
try:
try:
raise ValueError("propagating")
finally:
# Exception is propagating through here
while True:
time.sleep(0.01)
except:
pass # Never reached due to infinite loop
t = threading.Thread(target=target_thread)
t.start()
t.join()
""",
"finally_after_except": f"""\
import socket
import threading
import time
def target_thread():
'''Finally runs after except handled - exc_info is cleared'''
conn = socket.create_connection(("localhost", {port}))
conn.sendall(b"ready:" + str(threading.get_native_id()).encode())
try:
raise ValueError("test")
except ValueError:
pass # Exception caught and handled
finally:
while True:
time.sleep(0.01)
t = threading.Thread(target=target_thread)
t.start()
t.join()
""",
"finally_no_exception": f"""\
import socket
import threading
import time
def target_thread():
'''Finally with no exception at all'''
conn = socket.create_connection(("localhost", {port}))
conn.sendall(b"ready:" + str(threading.get_native_id()).encode())
try:
pass # No exception
finally:
while True:
time.sleep(0.01)
t = threading.Thread(target=target_thread)
t.start()
t.join()
""",
}
return scenarios[scenario]
@contextmanager
def _run_scenario_process(self, scenario):
"""Context manager to run a single scenario and yield thread ID and process."""
port = find_unused_port()
script = self._make_single_scenario_script(port, scenario)
with os_helper.temp_dir() as tmp_dir:
script_file = make_script(tmp_dir, "script", script)
server_socket = _create_server_socket(port, backlog=1)
client_socket = None
try:
with _managed_subprocess([sys.executable, script_file]) as p:
thread_tid = None
client_socket, _ = server_socket.accept()
line = client_socket.recv(1024)
if line and line.startswith(b"ready:"):
try:
thread_tid = int(line.split(b":")[-1])
except (ValueError, IndexError):
pass
server_socket.close()
server_socket = None
yield p, thread_tid
finally:
_cleanup_sockets(client_socket, server_socket)
def _check_thread_status(
self, p, thread_tid, condition, condition_name="condition"
):
"""Helper to check thread status with a custom condition.
This waits until we see 3 consecutive samples where the condition
returns True, which confirms the thread has reached and is stable
in the expected state. Samples that don't match are ignored (the
thread may not have reached the expected state yet).
Args:
p: Process object with pid attribute
thread_tid: Thread ID to check
condition: Callable(statuses, thread_tid) -> bool that returns
True when the thread is in the expected state
condition_name: Description of condition for error messages
"""
unwinder = RemoteUnwinder(
p.pid,
all_threads=True,
mode=PROFILING_MODE_ALL,
skip_non_matching_threads=False,
)
# Wait for 3 consecutive samples matching expected state
matching_samples = 0
for _ in busy_retry(SHORT_TIMEOUT):
with contextlib.suppress(*TRANSIENT_ERRORS):
traces = unwinder.get_stack_trace()
statuses = self._get_thread_statuses(traces)
if thread_tid in statuses:
if condition(statuses, thread_tid):
matching_samples += 1
if matching_samples >= 3:
return # Success - confirmed stable in expected state
else:
# Thread not yet in expected state, reset counter
matching_samples = 0
self.fail(
f"Thread did not stabilize in expected state "
f"({condition_name}) within timeout"
)
def _check_exception_status(self, p, thread_tid, expect_exception):
"""Helper to check if thread has expected exception status."""
def condition(statuses, tid):
has_exc = bool(statuses[tid] & THREAD_STATUS_HAS_EXCEPTION)
return has_exc == expect_exception
self._check_thread_status(
p, thread_tid, condition,
condition_name=f"expect_exception={expect_exception}"
)
@unittest.skipIf(
sys.platform not in ("linux", "darwin", "win32"),
"Test only runs on supported platforms (Linux, macOS, or Windows)",
)
@unittest.skipIf(
sys.platform == "android", "Android raises Linux-specific exception"
)
def test_except_block_has_exception(self):
"""Test that thread inside except block has HAS_EXCEPTION flag.
When a thread is executing inside an except block, exc_info->exc_value
is set, so THREAD_STATUS_HAS_EXCEPTION should be True.
"""
with self._run_scenario_process("except_block") as (p, thread_tid):
self.assertIsNotNone(thread_tid, "Thread ID not received")
self._check_exception_status(p, thread_tid, expect_exception=True)
@unittest.skipIf(
sys.platform not in ("linux", "darwin", "win32"),
"Test only runs on supported platforms (Linux, macOS, or Windows)",
)
@unittest.skipIf(
sys.platform == "android", "Android raises Linux-specific exception"
)
def test_finally_propagating_has_exception(self):
"""Test that finally block with propagating exception has HAS_EXCEPTION flag.
When an exception is propagating through a finally block (not yet caught),
current_exception is set, so THREAD_STATUS_HAS_EXCEPTION should be True.
"""
with self._run_scenario_process("finally_propagating") as (p, thread_tid):
self.assertIsNotNone(thread_tid, "Thread ID not received")
self._check_exception_status(p, thread_tid, expect_exception=True)
@unittest.skipIf(
sys.platform not in ("linux", "darwin", "win32"),
"Test only runs on supported platforms (Linux, macOS, or Windows)",
)
@unittest.skipIf(
sys.platform == "android", "Android raises Linux-specific exception"
)
def test_finally_after_except_no_exception(self):
"""Test that finally block after except has NO HAS_EXCEPTION flag.
When a finally block runs after an except block has handled the exception,
Python clears exc_info before entering finally, so THREAD_STATUS_HAS_EXCEPTION
should be False.
"""
with self._run_scenario_process("finally_after_except") as (p, thread_tid):
self.assertIsNotNone(thread_tid, "Thread ID not received")
self._check_exception_status(p, thread_tid, expect_exception=False)
@unittest.skipIf(
sys.platform not in ("linux", "darwin", "win32"),
"Test only runs on supported platforms (Linux, macOS, or Windows)",
)
@unittest.skipIf(
sys.platform == "android", "Android raises Linux-specific exception"
)
def test_finally_no_exception_no_flag(self):
"""Test that finally block with no exception has NO HAS_EXCEPTION flag.
When a finally block runs during normal execution (no exception raised),
there is no exception state, so THREAD_STATUS_HAS_EXCEPTION should be False.
"""
with self._run_scenario_process("finally_no_exception") as (p, thread_tid):
self.assertIsNotNone(thread_tid, "Thread ID not received")
self._check_exception_status(p, thread_tid, expect_exception=False)
@skip_if_not_supported
class TestExceptionDetectionInProcess(RemoteInspectionTestBase):
"""gh-158539: HAS_EXCEPTION for handlers running in generators/coroutines.
``TestExceptionDetectionScenarios`` samples a child process and therefore
needs subprocess debugging permissions. These tests inspect the current
process with ``RemoteUnwinder`` and only need self-inspection, so they also
run on macOS without special entitlements.
"""
@classmethod
def setUpClass(cls):
try:
RemoteUnwinder(os.getpid(), all_threads=True).get_stack_trace()
except PermissionError as exc:
raise unittest.SkipTest(f"self-inspection is unavailable: {exc}")
def _check_running_handler(
self, target, expect_exception, *, mode=PROFILING_MODE_ALL,
skip_non_matching_threads=False,
):
"""Run *target* in a thread and check its HAS_EXCEPTION flag.
*target* receives ``(ready, stop)`` events and must signal ``ready``
only once it is executing inside the code region under test, then keep
running until ``stop`` is set.
"""
stop = threading.Event()
ready = threading.Event()
failure = []
def runner():
try:
target(ready, stop)
except BaseException as exc:
failure.append(exc)
ready.set()
thread = threading.Thread(target=runner, daemon=True)
thread.start()
try:
self.assertTrue(ready.wait(SHORT_TIMEOUT), "handler never started")
self.assertFalse(failure, f"handler raised {failure!r}")
unwinder = RemoteUnwinder(
os.getpid(),
all_threads=True,
mode=mode,
skip_non_matching_threads=skip_non_matching_threads,
)
observed = []
for _ in busy_retry(SHORT_TIMEOUT):
with contextlib.suppress(*TRANSIENT_ERRORS):
statuses = self._get_thread_statuses(unwinder.get_stack_trace())
status = statuses.get(thread.native_id)
if status is None:
continue
has_exception = bool(status & THREAD_STATUS_HAS_EXCEPTION)
observed.append(has_exception)
if has_exception == expect_exception:
break
self.assertTrue(
observed, "target thread status was never observed"
)
self.assertIn(
expect_exception,
observed,
f"HAS_EXCEPTION was never {expect_exception} while the "
f"handler was running (observed {observed})",
)
finally:
stop.set()
thread.join(SHORT_TIMEOUT)
def _busy_until_stopped(self, ready, stop):
ready.set()
while not stop.is_set():
time.sleep(0.001)
def test_handler_in_function(self):
def target(ready, stop):
try:
raise ValueError("test")
except ValueError:
self._busy_until_stopped(ready, stop)
self._check_running_handler(target, expect_exception=True)
def test_handler_in_generator(self):
def target(ready, stop):
def gen():
try:
raise ValueError("test")
except ValueError:
self._busy_until_stopped(ready, stop)
yield
for _ in gen():
pass
self._check_running_handler(target, expect_exception=True)
def test_handler_in_genexpr_callee(self):
def target(ready, stop):
def callee():
try:
raise ValueError("test")
except ValueError:
self._busy_until_stopped(ready, stop)
list(callee() for _ in range(1))
self._check_running_handler(target, expect_exception=True)
def test_handler_in_coroutine(self):
async def coro(ready, stop):
try:
raise ValueError("test")
except ValueError:
self._busy_until_stopped(ready, stop)
def target(ready, stop):
asyncio.run(coro(ready, stop))
self._check_running_handler(target, expect_exception=True)
def test_handler_in_callee_from_coroutine(self):
def callee(ready, stop):
try:
raise ValueError("test")
except ValueError:
self._busy_until_stopped(ready, stop)
async def coro(ready, stop):
callee(ready, stop)
def target(ready, stop):
asyncio.run(coro(ready, stop))
self._check_running_handler(target, expect_exception=True)
def test_outer_handler_while_generator_runs(self):
"""A generator with no handler of its own must not hide the outer one.
``exc_info`` points at the generator's empty ``_PyErr_StackItem`` whose
``previous_item`` is the thread's ``exc_state``, so the profiler has to
walk the chain to find the exception ``sys.exception()`` reports.
"""
def target(ready, stop):
def gen():
self._busy_until_stopped(ready, stop)
yield
try:
raise ValueError("outer")
except ValueError:
for _ in gen():
pass
self._check_running_handler(target, expect_exception=True)
def test_generator_without_exception(self):
def target(ready, stop):
def gen():
self._busy_until_stopped(ready, stop)
yield
for _ in gen():
pass
self._check_running_handler(target, expect_exception=False)
def test_outer_handler_while_nested_generators_run(self):
def target(ready, stop):
def gen(depth):
if depth:
yield from gen(depth - 1)
else:
self._busy_until_stopped(ready, stop)
yield
try:
raise ValueError("outer")
except ValueError:
for _ in gen(32):
pass
self._check_running_handler(
target,
expect_exception=True,
mode=PROFILING_MODE_EXCEPTION,
skip_non_matching_threads=True,
)
def test_generator_finally_after_except(self):
"""The handled exception is cleared before the generator's finally."""
def target(ready, stop):
def gen():
try:
raise ValueError("test")
except ValueError:
pass
finally:
self._busy_until_stopped(ready, stop)
yield
for _ in gen():
pass
self._check_running_handler(target, expect_exception=False)
def test_exception_mode_filter_keeps_generator_handler(self):
"""The exception-mode thread filter must not drop a generator handler.
This mirrors what ``--mode=exception`` actually does: threads without
HAS_EXCEPTION are skipped before their stack is unwound.
"""
def target(ready, stop):
def gen():
try:
raise ValueError("test")
except ValueError:
self._busy_until_stopped(ready, stop)
yield
for _ in gen():
pass
self._check_running_handler(
target,
expect_exception=True,
mode=PROFILING_MODE_EXCEPTION,
skip_non_matching_threads=True,
)
@requires_remote_subprocess_debugging()
class TestFrameCaching(RemoteInspectionTestBase):
"""Test that frame caching produces correct results.
Uses socket-based synchronization for deterministic testing.
All tests verify cache reuse via object identity checks (assertIs).
"""
def _get_frames_with_retry(self, unwinder, required_funcs):
"""Get frames containing required_funcs, with retry for transient errors."""
for _ in range(MAX_TRIES):
with contextlib.suppress(*TRANSIENT_ERRORS):
traces = unwinder.get_stack_trace()
for interp in traces:
for thread in interp.threads:
funcs = {f.funcname for f in thread.frame_info}
if required_funcs.issubset(funcs):
return thread.frame_info
time.sleep(RETRY_DELAY)
return None
def _sample_frames(
self,
client_socket,
unwinder,
wait_signal,
send_ack,
required_funcs,
expected_frames=1,
):
"""Wait for signal, sample frames with retry until required funcs present, send ack."""
_wait_for_signal(client_socket, wait_signal)
frames = None
for _ in range(MAX_TRIES):
frames = self._get_frames_with_retry(unwinder, required_funcs)
if frames and len(frames) >= expected_frames:
break
time.sleep(RETRY_DELAY)
client_socket.sendall(send_ack)
return frames
@skip_if_not_supported
@unittest.skipIf(
sys.platform == "linux" and not PROCESS_VM_READV_SUPPORTED,
"Test only runs on Linux with process_vm_readv support",
)
def test_cache_hit_same_stack(self):
"""Test that consecutive samples reuse cached parent frame objects.
The current frame (index 0) is always re-read from memory to get
updated line numbers, so it may be a different object. Parent frames
(index 1+) should be identical objects from cache.
"""
script_body = """\
def level3():
sock.sendall(b"sync1")
sock.recv(16)
sock.sendall(b"sync2")
sock.recv(16)
sock.sendall(b"sync3")
sock.recv(16)
def level2():
level3()
def level1():
level2()
level1()
"""
with self._target_process(script_body) as (
p,
client_socket,
make_unwinder,
):
unwinder = make_unwinder(cache_frames=True)
expected = {"level1", "level2", "level3"}
frames1 = self._sample_frames(
client_socket, unwinder, b"sync1", b"ack", expected
)
frames2 = self._sample_frames(
client_socket, unwinder, b"sync2", b"ack", expected
)
frames3 = self._sample_frames(
client_socket, unwinder, b"sync3", b"done", expected
)
self.assertIsNotNone(frames1)
self.assertIsNotNone(frames2)
self.assertIsNotNone(frames3)
self.assertEqual(len(frames1), len(frames2))
self.assertEqual(len(frames2), len(frames3))
# Current frame (index 0) is always re-read, so check value equality
self.assertEqual(frames1[0].funcname, frames2[0].funcname)
self.assertEqual(frames2[0].funcname, frames3[0].funcname)
# Parent frames (index 1+) must be identical objects (cache reuse)
for i in range(1, len(frames1)):
f1, f2, f3 = frames1[i], frames2[i], frames3[i]
self.assertIs(
f1, f2, f"Frame {i}: samples 1-2 must be same object"
)
self.assertIs(
f2, f3, f"Frame {i}: samples 2-3 must be same object"
)
@skip_if_not_supported
@unittest.skipIf(
sys.platform == "linux" and not PROCESS_VM_READV_SUPPORTED,
"Test only runs on Linux with process_vm_readv support",
)
def test_line_number_updates_in_same_frame(self):
"""Test that line numbers are correctly updated when execution moves within a function.
When the profiler samples at different points within the same function,
it must report the correct line number for each sample, not stale cached values.
"""
script_body = """\
def outer():
inner()
def inner():
sock.sendall(b"line_a"); sock.recv(16)
sock.sendall(b"line_b"); sock.recv(16)
sock.sendall(b"line_c"); sock.recv(16)
sock.sendall(b"line_d"); sock.recv(16)
outer()
"""
with self._target_process(script_body) as (
p,
client_socket,
make_unwinder,
):
unwinder = make_unwinder(cache_frames=True)
frames_a = self._sample_frames(
client_socket, unwinder, b"line_a", b"ack", {"inner"}
)
frames_b = self._sample_frames(
client_socket, unwinder, b"line_b", b"ack", {"inner"}
)
frames_c = self._sample_frames(
client_socket, unwinder, b"line_c", b"ack", {"inner"}
)
frames_d = self._sample_frames(
client_socket, unwinder, b"line_d", b"done", {"inner"}
)
self.assertIsNotNone(frames_a)
self.assertIsNotNone(frames_b)
self.assertIsNotNone(frames_c)
self.assertIsNotNone(frames_d)
# Get the 'inner' frame from each sample (should be index 0)
inner_a = frames_a[0]
inner_b = frames_b[0]
inner_c = frames_c[0]
inner_d = frames_d[0]
self.assertEqual(inner_a.funcname, "inner")
self.assertEqual(inner_b.funcname, "inner")
self.assertEqual(inner_c.funcname, "inner")
self.assertEqual(inner_d.funcname, "inner")
# Line numbers must be different and increasing (execution moves forward)
self.assertLess(
inner_a.location.lineno, inner_b.location.lineno, "Line B should be after line A"
)
self.assertLess(
inner_b.location.lineno, inner_c.location.lineno, "Line C should be after line B"
)
self.assertLess(
inner_c.location.lineno, inner_d.location.lineno, "Line D should be after line C"
)
@skip_if_not_supported
@unittest.skipIf(
sys.platform == "linux" and not PROCESS_VM_READV_SUPPORTED,
"Test only runs on Linux with process_vm_readv support",
)
def test_cache_invalidation_on_return(self):
"""Test cache invalidation when stack shrinks (function returns)."""
script_body = """\
def inner():
sock.sendall(b"at_inner")
sock.recv(16)
def outer():
inner()
sock.sendall(b"at_outer")
sock.recv(16)
outer()
"""
with self._target_process(script_body) as (
p,
client_socket,
make_unwinder,
):
unwinder = make_unwinder(cache_frames=True)
frames_deep = self._sample_frames(
client_socket,
unwinder,
b"at_inner",
b"ack",
{"inner", "outer"},
)
frames_shallow = self._sample_frames(
client_socket, unwinder, b"at_outer", b"done", {"outer"}
)
self.assertIsNotNone(frames_deep)
self.assertIsNotNone(frames_shallow)
funcs_deep = [f.funcname for f in frames_deep]
funcs_shallow = [f.funcname for f in frames_shallow]
self.assertIn("inner", funcs_deep)
self.assertIn("outer", funcs_deep)
self.assertNotIn("inner", funcs_shallow)
self.assertIn("outer", funcs_shallow)
@skip_if_not_supported
@unittest.skipIf(
sys.platform == "linux" and not PROCESS_VM_READV_SUPPORTED,
"Test only runs on Linux with process_vm_readv support",
)
def test_cache_invalidation_on_call(self):
"""Test cache invalidation when stack grows (new function called)."""
script_body = """\
def deeper():
sock.sendall(b"at_deeper")
sock.recv(16)
def middle():
sock.sendall(b"at_middle")
sock.recv(16)
deeper()
def top():
middle()
top()
"""
with self._target_process(script_body) as (
p,
client_socket,
make_unwinder,
):
unwinder = make_unwinder(cache_frames=True)
frames_before = self._sample_frames(
client_socket,
unwinder,
b"at_middle",
b"ack",
{"middle", "top"},
)
frames_after = self._sample_frames(
client_socket,
unwinder,
b"at_deeper",
b"done",
{"deeper", "middle", "top"},
)
self.assertIsNotNone(frames_before)
self.assertIsNotNone(frames_after)
funcs_before = [f.funcname for f in frames_before]
funcs_after = [f.funcname for f in frames_after]
self.assertIn("middle", funcs_before)
self.assertIn("top", funcs_before)
self.assertNotIn("deeper", funcs_before)
self.assertIn("deeper", funcs_after)
self.assertIn("middle", funcs_after)
self.assertIn("top", funcs_after)
@skip_if_not_supported
@unittest.skipIf(
sys.platform == "linux" and not PROCESS_VM_READV_SUPPORTED,
"Test only runs on Linux with process_vm_readv support",
)
def test_partial_stack_reuse(self):
"""Test that unchanged parent frames are reused from cache when top frame moves."""
script_body = """\
def level4():
sock.sendall(b"sync1")
sock.recv(16)
sock.sendall(b"sync2")
sock.recv(16)
def level3():
level4()
def level2():
level3()
def level1():
level2()
level1()
"""
with self._target_process(script_body) as (
p,
client_socket,
make_unwinder,
):
unwinder = make_unwinder(cache_frames=True)
# Sample 1: level4 at first sendall
frames1 = self._sample_frames(
client_socket,
unwinder,
b"sync1",
b"ack",
{"level1", "level2", "level3", "level4"},
)
# Sample 2: level4 at second sendall (same stack, different line)
frames2 = self._sample_frames(
client_socket,
unwinder,
b"sync2",
b"done",
{"level1", "level2", "level3", "level4"},
)
self.assertIsNotNone(frames1)
self.assertIsNotNone(frames2)
def find_frame(frames, funcname):
for f in frames:
if f.funcname == funcname:
return f
return None
# level4 should have different line numbers (it moved)
l4_1 = find_frame(frames1, "level4")
l4_2 = find_frame(frames2, "level4")
self.assertIsNotNone(l4_1)
self.assertIsNotNone(l4_2)
self.assertNotEqual(
l4_1.location.lineno,
l4_2.location.lineno,
"level4 should be at different lines",
)
# Parent frames (level1, level2, level3) should be reused from cache
for name in ["level1", "level2", "level3"]:
f1 = find_frame(frames1, name)
f2 = find_frame(frames2, name)
self.assertIsNotNone(f1, f"{name} missing from sample 1")
self.assertIsNotNone(f2, f"{name} missing from sample 2")
self.assertIs(f1, f2, f"{name} should be reused from cache")
@skip_if_not_supported
@unittest.skipIf(
sys.platform == "linux" and not PROCESS_VM_READV_SUPPORTED,
"Test only runs on Linux with process_vm_readv support",
)
def test_recursive_frames(self):
"""Test caching with same function appearing multiple times (recursion)."""
script_body = """\
def recurse(n):
if n <= 0:
sock.sendall(b"sync1")
sock.recv(16)
sock.sendall(b"sync2")
sock.recv(16)
else:
recurse(n - 1)
recurse(5)
"""
with self._target_process(script_body) as (
p,
client_socket,
make_unwinder,
):
unwinder = make_unwinder(cache_frames=True)
frames1 = self._sample_frames(
client_socket, unwinder, b"sync1", b"ack", {"recurse"}
)
frames2 = self._sample_frames(
client_socket, unwinder, b"sync2", b"done", {"recurse"}
)
self.assertIsNotNone(frames1)
self.assertIsNotNone(frames2)
# Should have multiple "recurse" frames (6 total: recurse(5) down to recurse(0))
recurse_count = sum(1 for f in frames1 if f.funcname == "recurse")
self.assertEqual(recurse_count, 6, "Should have 6 recursive frames")
self.assertEqual(len(frames1), len(frames2))
# Current frame (index 0) is re-read, check value equality
self.assertEqual(frames1[0].funcname, frames2[0].funcname)
# Parent frames (index 1+) should be identical objects (cache reuse)
for i in range(1, len(frames1)):
self.assertIs(
frames1[i],
frames2[i],
f"Frame {i}: recursive frames must be same object",
)
@skip_if_not_supported
@unittest.skipIf(
sys.platform == "linux" and not PROCESS_VM_READV_SUPPORTED,
"Test only runs on Linux with process_vm_readv support",
)
def test_cache_vs_no_cache_equivalence(self):
"""Test that cache_frames=True and cache_frames=False produce equivalent results."""
script_body = """\
def level3():
sock.sendall(b"ready"); sock.recv(16)
def level2():
level3()
def level1():
level2()
level1()
"""
with self._target_process(script_body) as (
p,
client_socket,
make_unwinder,
):
_wait_for_signal(client_socket, b"ready")
# Sample with cache
unwinder_cache = make_unwinder(cache_frames=True)
frames_cached = self._get_frames_with_retry(
unwinder_cache, {"level1", "level2", "level3"}
)
# Sample without cache
unwinder_no_cache = make_unwinder(cache_frames=False)
frames_no_cache = self._get_frames_with_retry(
unwinder_no_cache, {"level1", "level2", "level3"}
)
client_socket.sendall(b"done")
self.assertIsNotNone(frames_cached)
self.assertIsNotNone(frames_no_cache)
# Same number of frames
self.assertEqual(len(frames_cached), len(frames_no_cache))
# Same function names in same order
funcs_cached = [f.funcname for f in frames_cached]
funcs_no_cache = [f.funcname for f in frames_no_cache]
self.assertEqual(funcs_cached, funcs_no_cache)
# For level3 (leaf frame), due to timing races we can be at either
# sock.sendall() or sock.recv() - both are valid. For parent frames,
# the locations should match exactly.
# Valid locations for level3: line 3 has two statements
# sock.sendall(b"ready") -> col 4-26
# sock.recv(16) -> col 28-41
level3_valid_cols = {(4, 26), (28, 41)}
for i in range(len(frames_cached)):
loc_cached = frames_cached[i].location
loc_no_cache = frames_no_cache[i].location
if frames_cached[i].funcname == "level3":
# Leaf frame: can be at either statement
self.assertIn(
(loc_cached.col_offset, loc_cached.end_col_offset),
level3_valid_cols,
)
self.assertIn(
(loc_no_cache.col_offset, loc_no_cache.end_col_offset),
level3_valid_cols,
)
else:
# Parent frames: must match exactly
self.assertEqual(loc_cached, loc_no_cache)
@skip_if_not_supported
@unittest.skipIf(
sys.platform == "linux" and not PROCESS_VM_READV_SUPPORTED,
"Test only runs on Linux with process_vm_readv support",
)
def test_cache_per_thread_isolation(self):
"""Test that frame cache is per-thread and cache invalidation works independently."""
script_body = """\
import threading
lock = threading.Lock()
def sync(msg):
with lock:
sock.sendall(msg + b"\\n")
sock.recv(1)
# Thread 1 functions
def baz1():
sync(b"t1:baz1")
def bar1():
baz1()
def blech1():
sync(b"t1:blech1")
def foo1():
bar1() # Goes down to baz1, syncs
blech1() # Returns up, goes down to blech1, syncs
# Thread 2 functions
def baz2():
sync(b"t2:baz2")
def bar2():
baz2()
def blech2():
sync(b"t2:blech2")
def foo2():
bar2() # Goes down to baz2, syncs
blech2() # Returns up, goes down to blech2, syncs
t1 = threading.Thread(target=foo1)
t2 = threading.Thread(target=foo2)
t1.start()
t2.start()
t1.join()
t2.join()
"""
with self._target_process(script_body) as (
p,
client_socket,
make_unwinder,
):
unwinder = make_unwinder(cache_frames=True)
# Message dispatch table: signal -> required functions for that thread
dispatch = {
b"t1:baz1": {"baz1", "bar1", "foo1"},
b"t2:baz2": {"baz2", "bar2", "foo2"},
b"t1:blech1": {"blech1", "foo1"},
b"t2:blech2": {"blech2", "foo2"},
}
# Track results for each sync point
results = {}
# Process 4 sync points (order depends on thread scheduling)
buffer = _wait_for_signal(client_socket, b"\n")
for i in range(4):
# Extract first message from buffer
msg, sep, buffer = buffer.partition(b"\n")
self.assertIn(msg, dispatch, f"Unexpected message: {msg!r}")
# Sample frames for the thread at this sync point
required_funcs = dispatch[msg]
frames = self._get_frames_with_retry(unwinder, required_funcs)
self.assertIsNotNone(frames, f"Thread not found for {msg!r}")
results[msg] = [f.funcname for f in frames]
# Release thread and wait for next message (if not last)
client_socket.sendall(b"k")
if i < 3:
buffer += _wait_for_signal(client_socket, b"\n")
# Validate Phase 1: baz snapshots
t1_baz = results.get(b"t1:baz1")
t2_baz = results.get(b"t2:baz2")
self.assertIsNotNone(t1_baz, "Missing t1:baz1 snapshot")
self.assertIsNotNone(t2_baz, "Missing t2:baz2 snapshot")
# Thread 1 at baz1: should have foo1->bar1->baz1
self.assertIn("baz1", t1_baz)
self.assertIn("bar1", t1_baz)
self.assertIn("foo1", t1_baz)
self.assertNotIn("blech1", t1_baz)
# No cross-contamination
self.assertNotIn("baz2", t1_baz)
self.assertNotIn("bar2", t1_baz)
self.assertNotIn("foo2", t1_baz)
# Thread 2 at baz2: should have foo2->bar2->baz2
self.assertIn("baz2", t2_baz)
self.assertIn("bar2", t2_baz)
self.assertIn("foo2", t2_baz)
self.assertNotIn("blech2", t2_baz)
# No cross-contamination
self.assertNotIn("baz1", t2_baz)
self.assertNotIn("bar1", t2_baz)
self.assertNotIn("foo1", t2_baz)
# Validate Phase 2: blech snapshots (cache invalidation test)
t1_blech = results.get(b"t1:blech1")
t2_blech = results.get(b"t2:blech2")
self.assertIsNotNone(t1_blech, "Missing t1:blech1 snapshot")
self.assertIsNotNone(t2_blech, "Missing t2:blech2 snapshot")
# Thread 1 at blech1: bar1/baz1 should be GONE (cache invalidated)
self.assertIn("blech1", t1_blech)
self.assertIn("foo1", t1_blech)
self.assertNotIn(
"bar1", t1_blech, "Cache not invalidated: bar1 still present"
)
self.assertNotIn(
"baz1", t1_blech, "Cache not invalidated: baz1 still present"
)
# No cross-contamination
self.assertNotIn("blech2", t1_blech)
# Thread 2 at blech2: bar2/baz2 should be GONE (cache invalidated)
self.assertIn("blech2", t2_blech)
self.assertIn("foo2", t2_blech)
self.assertNotIn(
"bar2", t2_blech, "Cache not invalidated: bar2 still present"
)
self.assertNotIn(
"baz2", t2_blech, "Cache not invalidated: baz2 still present"
)
# No cross-contamination
self.assertNotIn("blech1", t2_blech)
@skip_if_not_supported
@unittest.skipIf(
sys.platform == "linux" and not PROCESS_VM_READV_SUPPORTED,
"Test only runs on Linux with process_vm_readv support",
)
def test_new_unwinder_with_stale_last_profiled_frame(self):
"""Test that a new unwinder returns complete stack when cache lookup misses."""
script_body = """\
def level4():
sock.sendall(b"sync1")
sock.recv(16)
sock.sendall(b"sync2")
sock.recv(16)
def level3():
level4()
def level2():
level3()
def level1():
level2()
level1()
"""
with self._target_process(script_body) as (
p,
client_socket,
make_unwinder,
):
expected = {"level1", "level2", "level3", "level4"}
# First unwinder samples - this sets last_profiled_frame in target
unwinder1 = make_unwinder(cache_frames=True)
frames1 = self._sample_frames(
client_socket, unwinder1, b"sync1", b"ack", expected
)
# Create NEW unwinder (empty cache) and sample
# The target still has last_profiled_frame set from unwinder1
unwinder2 = make_unwinder(cache_frames=True)
frames2 = self._sample_frames(
client_socket, unwinder2, b"sync2", b"done", expected
)
self.assertIsNotNone(frames1)
self.assertIsNotNone(frames2)
funcs1 = [f.funcname for f in frames1]
funcs2 = [f.funcname for f in frames2]
# Both should have all levels
for level in ["level1", "level2", "level3", "level4"]:
self.assertIn(level, funcs1, f"{level} missing from first sample")
self.assertIn(level, funcs2, f"{level} missing from second sample")
# Should have same stack depth
self.assertEqual(
len(frames1),
len(frames2),
"New unwinder should return complete stack despite stale last_profiled_frame",
)
@skip_if_not_supported
@unittest.skipIf(
sys.platform == "linux" and not PROCESS_VM_READV_SUPPORTED,
"Test only runs on Linux with process_vm_readv support",
)
def test_cache_exhaustion(self):
"""Test cache works when frame limit (1024) is exceeded.
FRAME_CACHE_MAX_FRAMES=1024. With 1100 recursive frames,
the cache can't store all of them but should still work.
"""
# Use 1100 to exceed FRAME_CACHE_MAX_FRAMES=1024
depth = 1100
script_body = f"""\
import sys
sys.setrecursionlimit(2000)
def recurse(n):
if n <= 0:
sock.sendall(b"ready")
sock.recv(16) # wait for ack
sock.sendall(b"ready2")
sock.recv(16) # wait for done
return
recurse(n - 1)
recurse({depth})
"""
with self._target_process(script_body) as (
p,
client_socket,
make_unwinder,
):
unwinder_cache = make_unwinder(cache_frames=True)
unwinder_no_cache = make_unwinder(cache_frames=False)
frames_cached = self._sample_frames(
client_socket,
unwinder_cache,
b"ready",
b"ack",
{"recurse"},
expected_frames=1102,
)
# Sample again with no cache for comparison
frames_no_cache = self._sample_frames(
client_socket,
unwinder_no_cache,
b"ready2",
b"done",
{"recurse"},
expected_frames=1102,
)
self.assertIsNotNone(frames_cached)
self.assertIsNotNone(frames_no_cache)
# Both should have many recurse frames (> 1024 limit)
cached_count = [f.funcname for f in frames_cached].count("recurse")
no_cache_count = [f.funcname for f in frames_no_cache].count("recurse")
self.assertGreater(
cached_count, 1000, "Should have >1000 recurse frames"
)
self.assertGreater(
no_cache_count, 1000, "Should have >1000 recurse frames"
)
# Both modes should produce same frame count
self.assertEqual(
len(frames_cached),
len(frames_no_cache),
"Cache exhaustion should not affect stack completeness",
)
@skip_if_not_supported
@unittest.skipIf(
sys.platform == "linux" and not PROCESS_VM_READV_SUPPORTED,
"Test only runs on Linux with process_vm_readv support",
)
def test_get_stats(self):
"""Test that get_stats() returns statistics when stats=True."""
script_body = """\
sock.sendall(b"ready")
sock.recv(16)
"""
with self._target_process(script_body) as (p, client_socket, _):
unwinder = RemoteUnwinder(p.pid, all_threads=True, stats=True)
_wait_for_signal(client_socket, b"ready")
# Take a sample
_get_stack_trace_with_retry(unwinder)
stats = unwinder.get_stats()
client_socket.sendall(b"done")
# Verify expected keys exist
expected_keys = [
"total_samples",
"frame_cache_hits",
"frame_cache_misses",
"frame_cache_partial_hits",
"frames_read_from_cache",
"frames_read_from_memory",
"frame_cache_hit_rate",
"batched_read_attempts",
"batched_read_successes",
"batched_read_misses",
"batched_read_segments_requested",
"batched_read_segments_completed",
"batched_read_success_rate",
"batched_read_segment_completion_rate",
]
for key in expected_keys:
self.assertIn(key, stats)
self.assertEqual(stats["total_samples"], 1)
@skip_if_not_supported
@unittest.skipIf(
sys.platform == "linux" and not PROCESS_VM_READV_SUPPORTED,
"Test only runs on Linux with process_vm_readv support",
)
def test_get_stats_disabled_raises(self):
"""Test that get_stats() raises RuntimeError when stats=False."""
script_body = """\
sock.sendall(b"ready")
sock.recv(16)
"""
with self._target_process(script_body) as (p, client_socket, _):
unwinder = RemoteUnwinder(
p.pid, all_threads=True
) # stats=False by default
_wait_for_signal(client_socket, b"ready")
with self.assertRaises(RuntimeError):
unwinder.get_stats()
client_socket.sendall(b"done")
@requires_remote_subprocess_debugging()
@skip_if_not_supported
@unittest.skipIf(
sys.platform == "linux" and not PROCESS_VM_READV_SUPPORTED,
"Test only runs on Linux with process_vm_readv support",
)
class TestMetadataDegradation(RemoteInspectionTestBase):
"""Tests for graceful degradation of oversized code-object metadata."""
def test_long_qualname_truncated_not_dropped(self):
"""A qualname longer than 1024 chars is truncated instead of
failing the whole sample."""
name = "f" * 1100
src = f"def {name}(sample):\n return sample()\n"
ns = {}
exec(src, ns)
trace = ns[name](RemoteUnwinder(os.getpid()).get_stack_trace)
frame = self._find_frame_in_trace(
trace, lambda f: f.funcname.startswith("fff")
)
self.assertIsNotNone(frame)
self.assertEqual(frame.funcname, "f" * 1024)
def test_long_filename_truncated(self):
"""A filename longer than 1024 chars is truncated instead of
failing the whole sample."""
src = "def g(sample):\n return sample()\n"
ns = {}
exec(compile(src, "x" * 1500 + ".py", "exec"), ns)
trace = ns["g"](RemoteUnwinder(os.getpid()).get_stack_trace)
frame = self._find_frame_in_trace(trace, lambda f: f.funcname == "g")
self.assertIsNotNone(frame)
self.assertEqual(frame.filename, "x" * 1024)
def test_oversized_linetable_degrades_to_no_location(self):
"""A linetable over MAX_LINETABLE_SIZE degrades to a frame without
location instead of failing the whole sample."""
src = (
"def big(sample):\n"
+ " x = 1\n" * 20_000
+ " return sample()\n"
)
ns = {}
exec(compile(src, "big_linetable.py", "exec"), ns)
big = ns["big"]
self.assertGreater(len(big.__code__.co_linetable), 64 * 1024)
trace = big(RemoteUnwinder(os.getpid()).get_stack_trace)
frame = self._find_frame_in_trace(
trace, lambda f: f.funcname == "big"
)
self.assertIsNone(frame.location)
self.assertEqual(frame.filename, "big_linetable.py")
@unittest.skipIf(
sys.platform == "win32",
"Process death maps to ProcessLookupError only on POSIX platforms",
)
def test_dead_process_raises_not_degrades(self):
"""Death of the target raises ProcessLookupError instead of
degrading to synthetic frames."""
script_body = """\
import time
sock.sendall(b"ready")
time.sleep(10_000)
"""
with self._target_process(script_body) as (p, client_socket, make_unwinder):
_wait_for_signal(client_socket, b"ready")
unwinder = make_unwinder()
_get_stack_trace_with_retry(unwinder)
p.kill()
p.wait()
for _ in busy_retry(SHORT_TIMEOUT, error=False):
try:
unwinder.get_stack_trace()
except ProcessLookupError:
break
except RuntimeError:
continue
else:
self.fail("ProcessLookupError never raised for dead process")
@requires_remote_subprocess_debugging()
class TestFrameChainLimits(RemoteInspectionTestBase):
"""Frame chain walks abort instead of looping/overflowing on deep chains."""
# Limits plus one, to exceed them (must match MAX_FRAME_CHAIN_DEPTH /
# MAX_TASK_WAITER_WALK_TASKS from _remote_debugging.h)
FRAME_CHAIN_DEPTH = 1024 + 512 + 1
TASK_WAITER_WALK_TASKS = 2**14 + 1
def _assert_unwinder_limit_error(self, unwind, expected_substring):
"""Call unwind() until it raises the frame chain limit error.
unwind must construct the RemoteUnwinder and call it, so that
transient RuntimeErrors from either step are retried; a successful
call means the limit never triggered and fails immediately.
"""
last_error = None
for _ in busy_retry(SHORT_TIMEOUT, error=False):
try:
unwind()
except TRANSIENT_ERRORS as e:
if expected_substring in str(e):
return
last_error = e
continue
self.fail(
"frame chain limit did not trigger; call returned a result"
)
self.fail(
f"frame chain limit never raised; last transient error: "
f"{last_error!r}"
)
@skip_if_not_supported
@unittest.skipIf(
sys.platform == "linux" and not PROCESS_VM_READV_SUPPORTED,
"Test only runs on Linux with process_vm_readv support",
)
def test_get_stack_trace_deep_frame_chain_aborts(self):
"""Test that a frame chain deeper than the limit aborts the
synchronous stack walk instead of walking it indefinitely."""
script_body = f"""\
import sys
sys.setrecursionlimit({self.FRAME_CHAIN_DEPTH * 2})
def recurse(n):
if n <= 0:
sock.sendall(b"ready")
sock.recv(16)
return
recurse(n - 1)
recurse({self.FRAME_CHAIN_DEPTH})
"""
with self._target_process(script_body) as (p, client_socket, _):
_wait_for_signal(client_socket, b"ready")
self._assert_unwinder_limit_error(
lambda: RemoteUnwinder(p.pid).get_stack_trace(),
"Too many stack frames",
)
client_socket.sendall(b"done")
@skip_if_not_supported
@unittest.skipIf(
sys.platform == "linux" and not PROCESS_VM_READV_SUPPORTED,
"Test only runs on Linux with process_vm_readv support",
)
def test_get_async_stack_trace_deep_task_waiter_chain_aborts(self):
"""Test that a task waiter chain deeper than the limit aborts
the walk instead of overflowing the C stack."""
script_body = f"""\
import asyncio
async def chain(n):
if n <= 0:
sock.sendall(b"ready")
sock.recv(16)
return
task = asyncio.create_task(chain(n - 1))
await task
asyncio.run(chain({self.TASK_WAITER_WALK_TASKS}))
"""
with self._target_process(script_body) as (p, client_socket, _):
_wait_for_signal(client_socket, b"ready")
self._assert_unwinder_limit_error(
lambda: RemoteUnwinder(p.pid).get_async_stack_trace(),
"Too many task waiters",
)
client_socket.sendall(b"done")
@skip_if_not_supported
@unittest.skipIf(
sys.platform == "linux" and not PROCESS_VM_READV_SUPPORTED,
"Test only runs on Linux with process_vm_readv support",
)
def test_get_async_stack_trace_deep_frame_chain_aborts(self):
"""Test that a frame chain deeper than the limit aborts the async
stack walk instead of walking it indefinitely."""
script_body = f"""\
import sys, asyncio
sys.setrecursionlimit({self.FRAME_CHAIN_DEPTH * 2})
def recurse(n):
if n <= 0:
sock.sendall(b"ready")
sock.recv(16)
return
recurse(n - 1)
async def deep():
recurse({self.FRAME_CHAIN_DEPTH})
asyncio.run(deep())
"""
with self._target_process(script_body) as (p, client_socket, _):
_wait_for_signal(client_socket, b"ready")
self._assert_unwinder_limit_error(
lambda: RemoteUnwinder(p.pid).get_async_stack_trace(),
"Too many async stack frames",
)
client_socket.sendall(b"done")
@skip_if_not_supported
@unittest.skipIf(
sys.platform == "linux" and not PROCESS_VM_READV_SUPPORTED,
"Test only runs on Linux with process_vm_readv support",
)
def test_get_all_awaited_by_deep_coro_chain_aborts(self):
"""Test that a coroutine await chain deeper than the limit aborts
the walk instead of overflowing the C stack."""
script_body = f"""\
import sys, asyncio
sys.setrecursionlimit({self.FRAME_CHAIN_DEPTH * 2})
async def chain(n):
if n <= 0:
await asyncio.sleep(10_000)
return
await chain(n - 1)
async def main():
task = asyncio.create_task(chain({self.FRAME_CHAIN_DEPTH}))
await asyncio.sleep(0)
sock.sendall(b"ready")
await task
asyncio.run(main())
"""
with self._target_process(script_body) as (p, client_socket, _):
_wait_for_signal(client_socket, b"ready")
self._assert_unwinder_limit_error(
lambda: RemoteUnwinder(p.pid).get_all_awaited_by(),
"Too many coroutine frames",
)
if __name__ == "__main__":
unittest.main()