Revert "tests(memusage): make integration tests synchronous to avoid stray logs"

This reverts commit f086940b0a.

tests/test_memusage_integration.py

@@ -4,10 +4,10 @@ import logging
 import sys
 
 import pytest
-from twisted.internet import defer
 from twisted.internet.defer import inlineCallbacks
 
 from scrapy import signals
+from scrapy.extensions import memusage as memusage_mod
 from scrapy.extensions.memusage import MemoryUsage
 from scrapy.spiders import Spider
 from scrapy.utils.test import get_crawler
@@ -36,18 +36,21 @@ class _LoopSpider(Spider):
             )
 
 
-def _engine_started_once(self: MemoryUsage):
-    """
-    Test-only replacement for MemoryUsage.engine_started:
-    run checks once, synchronously; do not schedule periodic LoopingCalls.
-    """
-    # keep side-effects identical to a single immediate tick
-    self.update()
-    if self.limit:
-        self._check_limit()
-    if self.warning:
-        self._check_warning()
-    return defer.succeed(None)
+class _OneShotLoop:
+    """Test stub for create_looping_call: run once immediately, no background task."""
+
+    def __init__(self, func):
+        self.func = func
+        self.running = False
+
+    def start(self, _interval, now: bool = False, **_kw):
+        self.running = True
+        if now:
+            self.func()
+        return self
+
+    def stop(self):
+        self.running = False
 
 
 @inlineCallbacks
@@ -60,10 +63,8 @@ def test_memusage_limit_closes_spider_with_reason_and_error_log(caplog, monkeypa
         "LOG_LEVEL": "INFO",
     }
 
-    # Avoid background timers; run memusage checks once synchronously.
-    monkeypatch.setattr(
-        MemoryUsage, "engine_started", _engine_started_once, raising=True
-    )
+    # Avoid background LoopingCall that can log after the test finishes.
+    monkeypatch.setattr(memusage_mod, "create_looping_call", lambda f: _OneShotLoop(f))
 
     MB = 1024 * 1024
     state = {"high": False}
@@ -71,7 +72,7 @@ def test_memusage_limit_closes_spider_with_reason_and_error_log(caplog, monkeypa
     def fake_vsz(self):
         return 250 * MB if state["high"] else 5 * MB
 
-    monkeypatch.setattr(MemoryUsage, "get_virtual_size", fake_vsz, raising=True)
+    monkeypatch.setattr(MemoryUsage, "get_virtual_size", fake_vsz)
 
     crawler = get_crawler(spidercls=_LoopSpider, settings_dict=settings)
 
@@ -100,15 +101,11 @@ def test_memusage_warning_logs_but_allows_normal_finish(caplog, monkeypatch):
         "LOG_LEVEL": "INFO",
     }
 
-    # Avoid background timers; run memusage checks once synchronously.
-    monkeypatch.setattr(
-        MemoryUsage, "engine_started", _engine_started_once, raising=True
-    )
+    # Avoid background LoopingCall that can log after the test finishes.
+    monkeypatch.setattr(memusage_mod, "create_looping_call", lambda f: _OneShotLoop(f))
 
     MB = 1024 * 1024
-    monkeypatch.setattr(
-        MemoryUsage, "get_virtual_size", lambda self: 75 * MB, raising=True
-    )
+    monkeypatch.setattr(MemoryUsage, "get_virtual_size", lambda self: 75 * MB)
 
     crawler = get_crawler(spidercls=_LoopSpider, settings_dict=settings)