[Telemetry] Reorganize everything.

tools/telemetry/telemetry/multi_page_benchmark.py

-# Copyright (c) 2012 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.
-from telemetry import page_test
-
-class MeasurementFailure(page_test.Failure):
-  """Exception that can be thrown from MeasurePage to indicate an undesired but
-  designed-for problem."""
-  pass
-
-# TODO(nduca): Rename to page_benchmark
-class MultiPageBenchmark(page_test.PageTest):
-  """Glue code for running a benchmark across a set of pages.
-
-  To use this, subclass from the benchmark and override MeasurePage. For
-  example:
-
-     class BodyChildElementBenchmark(MultiPageBenchmark):
-        def MeasurePage(self, page, tab, results):
-           body_child_count = tab.EvaluateJavaScript(
-               'document.body.children.length')
-           results.Add('body_children', 'count', body_child_count)
-
-     if __name__ == '__main__':
-         multi_page_benchmark.Main(BodyChildElementBenchmark())
-
-  All benchmarks should include a unit test!
-
-     TODO(nduca): Add explanation of how to write the unit test.
-
-  To add test-specific options:
-
-     class BodyChildElementBenchmark(MultiPageBenchmark):
-        def AddCommandLineOptions(parser):
-           parser.add_option('--element', action='store', default='body')
-
-        def MeasurePage(self, page, tab, results):
-           body_child_count = tab.EvaluateJavaScript(
-              'document.querySelector('%s').children.length')
-           results.Add('children', 'count', child_count)
-  """
-  def __init__(self,
-               action_name_to_run='',
-               needs_browser_restart_after_each_run=False):
-    super(MultiPageBenchmark, self).__init__(
-      '_RunTest',
-      action_name_to_run,
-      needs_browser_restart_after_each_run)
-
-  def _RunTest(self, page, tab, results):
-    results.WillMeasurePage(page)
-    self.MeasurePage(page, tab, results)
-    results.DidMeasurePage()
-
-  @property
-  def results_are_the_same_on_every_page(self):
-    """By default, benchmarks are assumed to output the same values for every
-    page. This allows incremental output, for example in CSV. If, however, the
-    benchmark discovers what values it can report as it goes, and those values
-    may vary from page to page, you need to override this function and return
-    False. Output will not appear in this mode until the entire pageset has
-    run."""
-    return True
-
-  def MeasurePage(self, page, tab, results):
-    """Override to actually measure the page's performance.
-
-    page is a page_set.Page
-    tab is an instance of telemetry.Tab
-
-    Should call results.Add(name, units, value) for each result, or raise an
-    exception on failure. The name and units of each Add() call must be
-    the same across all iterations. The name 'url' must not be used.
-
-    Prefer field names that are in accordance with python variable style. E.g.
-    field_name.
-
-    Put together:
-
-       def MeasurePage(self, page, tab, results):
-         res = tab.EvaluateJavaScript('2+2')
-         if res != 4:
-           raise Exception('Oh, wow.')
-         results.Add('two_plus_two', 'count', res)
-    """
-    raise NotImplementedError()