tests(memusage): integration coverage with CI-safe reactor pinning and log assertions

tests/test_memusage_integration.py

@@ -16,7 +16,7 @@ from scrapy.extensions.memusage import MemoryUsage
 from scrapy.settings import Settings
 from scrapy.spiders import Spider
 
-# Skip on Windows; memusage relies on 'resource'
+# Memusage relies on 'resource' (Unix only).
 pytestmark = pytest.mark.skipif(
     sys.platform.startswith("win"),
     reason="MemoryUsage extension not available on Windows",
@@ -24,7 +24,7 @@ pytestmark = pytest.mark.skipif(
 
 
 class _LoopSpider(Spider):
-    """Keep the crawl alive long enough for periodic checks to run."""
+    """Keeps the engine running long enough for periodic checks."""
 
     name = "loop-file-spider"
 
@@ -44,10 +44,23 @@ class _LoopSpider(Spider):
 
 def _tmp_file_uri(tmp_path: Path) -> str:
     f = tmp_path / "hello.txt"
-    f.write_text("hello\\n")
+    f.write_text("hello\n")
     return f.as_uri()
 
 
+def _pin_reactor_to_installed(settings: Settings) -> None:
+    """Honor the reactor already installed by the test env/CI."""
+    from twisted.internet import (
+        reactor as _reactor,  # local import to avoid import-time issues
+    )
+
+    settings.set(
+        "TWISTED_REACTOR",
+        f"{_reactor.__class__.__module__}.{_reactor.__class__.__name__}",
+        priority="cmdline",
+    )
+
+
 @inlineCallbacks
 @pytest.mark.twisted
 def test_memusage_limit_closes_spider_with_reason_and_error_log(
@@ -62,8 +75,8 @@ def test_memusage_limit_closes_spider_with_reason_and_error_log(
             "LOG_LEVEL": "INFO",
         }
     )
+    _pin_reactor_to_installed(settings)
 
-    # Start LOW, flip HIGH only after spider is opened.
     MB = 1024 * 1024
     state = {"high": False}
 
@@ -75,19 +88,18 @@ def test_memusage_limit_closes_spider_with_reason_and_error_log(
     runner = CrawlerRunner(settings)
     crawler = runner.create_crawler(_LoopSpider)
 
-    # Use the correct kwarg name from the signal: 'spider'
     def on_opened(spider):
         state["high"] = True
 
     crawler.signals.connect(on_opened, signal=signals.spider_opened)
 
     caplog.set_level(logging.ERROR, logger="scrapy.extensions.memusage")
-    yield runner.crawl(crawler, url=url, loops=60)  # plenty of time for checks
+    yield runner.crawl(crawler, url=url, loops=100)
 
-    # Assert finish reason via stats (black-box)
     assert crawler.stats.get_value("finish_reason") == "memusage_exceeded"
-    # Assert the ERROR log message was emitted
-    assert any("memory usage exceeded" in r.message.lower() for r in caplog.records)
+    assert any(
+        "memory usage exceeded" in r.getMessage().lower() for r in caplog.records
+    )
 
 
 @inlineCallbacks
@@ -98,28 +110,26 @@ def test_memusage_warning_logs_but_allows_normal_finish(tmp_path, caplog, monkey
         {
             "MEMUSAGE_ENABLED": True,
             "MEMUSAGE_WARNING_MB": 50,
-            "MEMUSAGE_LIMIT_MB": 0,  # no hard limit
+            "MEMUSAGE_LIMIT_MB": 0,
             "MEMUSAGE_CHECK_INTERVAL_SECONDS": 0.01,
             "LOG_LEVEL": "INFO",
         }
     )
+    _pin_reactor_to_installed(settings)
 
     MB = 1024 * 1024
-    # Always above warning, never limited
     monkeypatch.setattr(MemoryUsage, "get_virtual_size", lambda self: 75 * MB)
 
     runner = CrawlerRunner(settings)
     crawler = runner.create_crawler(_LoopSpider)
 
     caplog.set_level(logging.WARNING, logger="scrapy.extensions.memusage")
-    yield runner.crawl(crawler, url=url, loops=40)
+    yield runner.crawl(crawler, url=url, loops=60)
 
-    # Normal completion
     assert crawler.stats.get_value("finish_reason") == "finished"
-    # Warning log appeared (match actual message)
     assert any(
-        "memory usage reached" in r.message.lower()
-        or "memory usage warning" in r.message.lower()
-        or "warning: memory usage reached" in r.message.lower()
+        ("memory usage reached" in r.getMessage().lower())
+        or ("memory usage warning" in r.getMessage().lower())
+        or ("warning: memory usage reached" in r.getMessage().lower())
         for r in caplog.records
     )