Drop DidStartHTTPServer to simplify object interactions.

tools/perf/measurements/page_cycler_unittest.py

 # Copyright 2013 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 import unittest
 
 from telemetry.core import browser_options
 from telemetry.page import page_runner
 from telemetry.results import page_test_results
 from telemetry.unittest import simple_mock
@@ skipping 20 matching lines @@
     pass
 
   def AddSummaryResults(self, tab, results):
     pass
 
 
 class FakePage(object):
   """Used to mock loading a page."""
   def __init__(self, url):
     self.url = url
+    self.is_file = url.startswith('file://')
 
 
 class FakeTab(object):
   """Used to mock a browser tab."""
   def __init__(self):
     self.clear_cache_calls = 0
+    self.navigated_urls = []
   def ClearCache(self, force=False):
     assert force
     self.clear_cache_calls += 1
   def EvaluateJavaScript(self, _):
     return 1
+  def Navigate(self, url):
+    self.navigated_urls.append(url)
   def WaitForJavaScriptExpression(self, _, __):
     pass
   @property
   def browser(self):
     return FakeBrowser()
 
 class FakeBrowser(object):
   _iteration = 0
 
   @property
   def cpu_stats(self):
     FakeBrowser._iteration += 1
     return {
         'Browser': {'CpuProcessTime': FakeBrowser._iteration,
                     'TotalTime': FakeBrowser._iteration * 2},
         'Renderer': {'CpuProcessTime': FakeBrowser._iteration,
                     'TotalTime': FakeBrowser._iteration * 3},
         'Gpu': {'CpuProcessTime': FakeBrowser._iteration,
                  'TotalTime': FakeBrowser._iteration * 4}
     }
   @property
   def platform(self):
     return FakePlatform()
 
+  @property
+  def http_server(self):
+    class FakeHttpServer(object):
+      def UrlOf(self, url_path):
+        return 'http://fakeserver:99999/%s' % url_path
+    return FakeHttpServer()
+
 
 class FakePlatform(object):
   def GetOSName(self):
     return 'fake'
   def CanMonitorPower(self):
     return False
 
 
 class PageCyclerUnitTest(unittest.TestCase):
 
@@ skipping 120 matching lines @@
         self.assertEqual(values[0].name, '%s.page_load_time' % chart_name)
         self.assertEqual(values[0].units, 'ms')
 
         for value, expected in zip(values[1:], ['gpu', 'renderer', 'browser']):
           self.assertEqual(value.page, page)
           self.assertEqual(value.name,
                            'cpu_utilization.cpu_utilization_%s' % expected)
           self.assertEqual(value.units, '%')
 
         cycler.DidNavigateToPage(page, tab)
+
+  def testLegacyPagesAvoidCrossRenderNavigation(self):
+    # For legacy page cyclers with file URLs, verify that WillNavigateToPage
+    # does an initial navigate to avoid paying for a cross-renderer navigation.
+    cycler = self.SetUpCycler([], True)
+    pages = [FakePage('file://fakepage1.com'), FakePage('file://fakepage2.com')]
+    tab = FakeTab()
+
+    self.assertEqual([], tab.navigated_urls)
+    for page in pages * 2:
+      cycler.WillNavigateToPage(page, tab)
+      self.assertEqual(
+          ['http://fakeserver:99999/nonexistent.html'], tab.navigated_urls)