[Telemetry] Fix bug in markers for cache temperature

telemetry/telemetry/page/cache_temperature_unittest.py

Index: telemetry/telemetry/page/cache_temperature_unittest.py
diff --git a/telemetry/telemetry/page/cache_temperature_unittest.py b/telemetry/telemetry/page/cache_temperature_unittest.py
index cc5cb1f353c26bb8a9ac38601ccba44b9bb51de4..e92e1571c4fedeb965280785f056a83fae75f2c2 100644
--- a/telemetry/telemetry/page/cache_temperature_unittest.py
+++ b/telemetry/telemetry/page/cache_temperature_unittest.py
@@ -2,43 +2,92 @@
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
+import contextlib
+
 from telemetry import decorators
 from telemetry import page as page_module
 from telemetry import story
 from telemetry.page import cache_temperature
 from telemetry.testing import browser_test_case
+from telemetry.timeline import trace_data
+from telemetry.timeline import tracing_config
+
 
 class CacheTempeartureTests(browser_test_case.BrowserTestCase):
+  def __init__(self, *args, **kwargs):
+    super(CacheTempeartureTests, self).__init__(*args, **kwargs)
+    self._full_trace = None
+
+  @contextlib.contextmanager
+  def captureTrace(self):
+    tracing_controller = self._browser.platform.tracing_controller
+    options = tracing_config.TracingConfig()
+    options.enable_chrome_trace = True
+    tracing_controller.StartTracing(options)
+    try:
+      yield
+    finally:
+      self._full_trace = tracing_controller.StopTracing()
+
+  def traceMarkers(self):
+    if not self._full_trace:
+      return set()
+
+    chrome_trace = self._full_trace.GetTraceFor(trace_data.CHROME_TRACE_PART)
+    return set(
+        event['name']
+        for event in chrome_trace['traceEvents']
+        if event['cat'] == 'blink.console')
+
   @decorators.Enabled('has tabs')
   def testEnsureAny(self):
-    story_set = story.StorySet()
-    page = page_module.Page('http://google.com', page_set=story_set,
-        cache_temperature=cache_temperature.ANY)
-    cache_temperature.EnsurePageCacheTemperature(page, self._browser)
+    with self.captureTrace():
+      story_set = story.StorySet()
+      page = page_module.Page('http://google.com', page_set=story_set,
+          cache_temperature=cache_temperature.ANY)
+      cache_temperature.EnsurePageCacheTemperature(page, self._browser)
+
+    markers = self.traceMarkers()
+    self.assertNotIn('telemetry.internal.ensure_diskcache.start', markers)
+    self.assertNotIn('telemetry.internal.warmCache.start', markers)
 
   @decorators.Enabled('has tabs')
   def testEnsurePCv1Cold(self):
-    story_set = story.StorySet()
-    page = page_module.Page('http://google.com', page_set=story_set,
-        cache_temperature=cache_temperature.PCV1_COLD)
-    cache_temperature.EnsurePageCacheTemperature(page, self._browser)
+    with self.captureTrace():
+      story_set = story.StorySet()
+      page = page_module.Page('http://google.com', page_set=story_set,
+          cache_temperature=cache_temperature.PCV1_COLD)
+      cache_temperature.EnsurePageCacheTemperature(page, self._browser)
+
+    markers = self.traceMarkers()
+    self.assertIn('telemetry.internal.ensure_diskcache.start', markers)
+    self.assertIn('telemetry.internal.ensure_diskcache.end', markers)
 
   @decorators.Enabled('has tabs')
   def testEnsurePCv1WarmAfterPCv1ColdRun(self):
-    story_set = story.StorySet()
-    page = page_module.Page('http://google.com', page_set=story_set,
-        cache_temperature=cache_temperature.PCV1_COLD)
-    cache_temperature.EnsurePageCacheTemperature(page, self._browser)
+    with self.captureTrace():
+      story_set = story.StorySet()
+      page = page_module.Page('http://google.com', page_set=story_set,
+          cache_temperature=cache_temperature.PCV1_COLD)
+      cache_temperature.EnsurePageCacheTemperature(page, self._browser)
 
-    previous_page = page
-    page = page_module.Page('http://google.com', page_set=story_set,
-        cache_temperature=cache_temperature.PCV1_WARM)
-    cache_temperature.EnsurePageCacheTemperature(page, self._browser,
-        previous_page)
+      previous_page = page
+      page = page_module.Page('http://google.com', page_set=story_set,
+          cache_temperature=cache_temperature.PCV1_WARM)
+      cache_temperature.EnsurePageCacheTemperature(page, self._browser,
+          previous_page)
+
+    markers = self.traceMarkers()
+    self.assertNotIn('telemetry.internal.warmCache.start', markers)
 
   @decorators.Enabled('has tabs')
   def testEnsurePCv1WarmFromScratch(self):
-    story_set = story.StorySet()
-    page = page_module.Page('http://google.com', page_set=story_set,
-        cache_temperature=cache_temperature.PCV1_WARM)
-    cache_temperature.EnsurePageCacheTemperature(page, self._browser)
+    with self.captureTrace():
+      story_set = story.StorySet()
+      page = page_module.Page('http://google.com', page_set=story_set,
+          cache_temperature=cache_temperature.PCV1_WARM)
+      cache_temperature.EnsurePageCacheTemperature(page, self._browser)
+
+    markers = self.traceMarkers()
+    self.assertIn('telemetry.internal.warmCache.start', markers)
+    self.assertIn('telemetry.internal.warmCache.end', markers)