playwright-python/tests/test_reference_count_async.py

135 lines
4.7 KiB
Python

# Copyright (c) Microsoft Corporation.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
import gc
import os
import tempfile
from collections import defaultdict
from typing import Any
import objgraph
import pytest
from playwright.async_api import async_playwright
from tests.server import Server
@pytest.mark.asyncio
async def test_memory_objects(server: Server, browser_name: str) -> None:
async with async_playwright() as p:
browser = await p[browser_name].launch()
page = await browser.new_page()
await page.goto(server.EMPTY_PAGE)
page.on("dialog", lambda dialog: dialog.dismiss())
for _ in range(100):
await page.evaluate("""async () => alert()""")
await page.route("**/*", lambda route, _: route.fulfill(body="OK"))
def handle_network_response_received(event: Any) -> None:
event["__pw__is_last_network_response_received_event"] = True
if browser_name == "chromium":
# https://github.com/microsoft/playwright-python/issues/1602
client = await page.context.new_cdp_session(page)
await client.send("Network.enable")
client.on(
"Network.responseReceived",
handle_network_response_received,
)
for _ in range(100):
response = await page.evaluate("""async () => (await fetch("/")).text()""")
assert response == "OK"
await browser.close()
gc.collect()
pw_objects: defaultdict = defaultdict(int)
for o in objgraph.by_type("dict"):
assert isinstance(o, dict)
name = o.get("_type")
# https://github.com/microsoft/playwright-python/issues/1602
if o.get("__pw__is_last_network_response_received_event", False):
assert False
if not name:
continue
pw_objects[name] += 1
assert "Dialog" not in pw_objects
assert "Request" not in pw_objects
assert "Route" not in pw_objects
@pytest.mark.asyncio
async def test_tracing_should_not_leak_protocol_callbacks(browser_name: str) -> None:
"""
Regression test for https://github.com/microsoft/playwright-python/issues/2977
This test ensures that ProtocolCallback objects don't accumulate when tracing is enabled.
The memory leak occurred because no_reply callbacks were created with circular references
but never cleaned up.
"""
def count_protocol_callbacks() -> int:
"""Count ProtocolCallback objects in memory."""
gc.collect()
count = 0
for obj in gc.get_objects():
if (
hasattr(obj, "__class__")
and obj.__class__.__name__ == "ProtocolCallback"
):
count += 1
return count
with tempfile.TemporaryDirectory() as temp_dir:
trace_file = os.path.join(temp_dir, "test_trace.zip")
async with async_playwright() as p:
browser = await p[browser_name].launch()
context = await browser.new_context()
# Start tracing to trigger the creation of no_reply callbacks
await context.tracing.start(screenshots=True, snapshots=True)
initial_count = count_protocol_callbacks()
# Perform operations that would create tracing callbacks
for _ in range(3):
page = await context.new_page()
await page.goto("data:text/html,<h1>Test Page</h1>")
await page.wait_for_load_state("networkidle")
await page.evaluate(
"document.querySelector('h1').textContent = 'Modified'"
)
await page.close()
# Stop tracing
await context.tracing.stop(path=trace_file)
await browser.close()
# Force garbage collection and check callback count
gc.collect()
final_count = count_protocol_callbacks()
# The key assertion: callback count should not have increased significantly
# Allow for a small number of legitimate callbacks but ensure no major leak
assert (
final_count - initial_count <= 5
), f"ProtocolCallback leak detected: initial={initial_count}, final={final_count}, leaked={final_count - initial_count}"