[telemetry] Add support for BenchmarkResults that vary from page to page

tools/telemetry/telemetry/csv_page_benchmark_results_unittest.py

Index: tools/telemetry/telemetry/csv_page_benchmark_results_unittest.py
diff --git a/tools/telemetry/telemetry/csv_page_benchmark_results_unittest.py b/tools/telemetry/telemetry/csv_page_benchmark_results_unittest.py
new file mode 100644
index 0000000000000000000000000000000000000000..db57b3520e4bbbad1aed07153744634a0cd394e0
--- /dev/null
+++ b/tools/telemetry/telemetry/csv_page_benchmark_results_unittest.py
@@ -0,0 +1,106 @@
+# 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.
+import StringIO
+import csv
+import os
+import unittest
+
+from telemetry.csv_page_benchmark_results import CsvPageBenchmarkResults
+from telemetry.page_set import PageSet
+
+def _MakePageSet():
+  return PageSet.FromDict({
+      "description": "hello",
+      "archive_path": "foo.wpr",
+      "pages": [
+        {"url": "http://www.foo.com/"},
+        {"url": "http://www.bar.com/"}
+        ]
+      }, os.path.dirname(__file__))
+
+class NonPrintingCsvPageBenchmarkResults(CsvPageBenchmarkResults):
+  def __init__(self, *args):
+    super(NonPrintingCsvPageBenchmarkResults, self).__init__(*args)
+
+  def _PrintPerfResult(self, *args):
+    pass
+
+class CsvPageBenchmarkResultsTest(unittest.TestCase):
+  def setUp(self):
+    self._output = StringIO.StringIO()
+    self._page_set = _MakePageSet()
+
+  @property
+  def lines(self):
+    lines = StringIO.StringIO(self._output.getvalue()).readlines()
+    return lines
+
+  @property
+  def output_header_row(self):
+    rows = list(csv.reader(self.lines))
+    return rows[0]
+
+  @property
+  def output_data_rows(self):
+    rows = list(csv.reader(self.lines))
+    return rows[1:]
+
+  def test_with_output_after_every_page(self):
+    results = NonPrintingCsvPageBenchmarkResults(csv.writer(self._output), True)
+    results.WillMeasurePage(self._page_set[0])
+    results.Add('foo', 'seconds', 3)
+    results.DidMeasurePage()
+    self.assertEquals(
+      self.output_header_row,
+      ['url', 'foo (seconds)'])
+    self.assertEquals(
+      self.output_data_rows[0],
+      [self._page_set[0].url, '3'])
+
+    results.WillMeasurePage(self._page_set[1])
+    results.Add('foo', 'seconds', 4)
+    results.DidMeasurePage()
+    self.assertEquals(
+      len(self.output_data_rows),
+      2)
+    self.assertEquals(
+      self.output_data_rows[1],
+      [self._page_set[1].url, '4'])
+
+  def test_with_output_after_every_page_and_inconsistency(self):
+    results = NonPrintingCsvPageBenchmarkResults(csv.writer(self._output), True)
+    results.WillMeasurePage(self._page_set[0])
+    results.Add('foo', 'seconds', 3)
+    results.DidMeasurePage()
+
+    # We printed foo, now change to bar
+    results.WillMeasurePage(self._page_set[1])
+    results.Add('bar', 'seconds', 4)
+
+    self.assertRaises(
+      Exception,
+      lambda: results.DidMeasurePage()) # pylint: disable=W0108
+
+  def test_with_output_at_print_summary_time(self):
+    results = NonPrintingCsvPageBenchmarkResults(csv.writer(self._output),
+                                                 False)
+    results.WillMeasurePage(self._page_set[0])
+    results.Add('foo', 'seconds', 3)
+    results.DidMeasurePage()
+
+    results.WillMeasurePage(self._page_set[1])
+    results.Add('bar', 'seconds', 4)
+    results.DidMeasurePage()
+
+    results.PrintSummary('tag')
+
+    self.assertEquals(
+      self.output_header_row,
+      ['url', 'bar (seconds)', 'foo (seconds)'])
+    self.assertEquals(
+      self.output_data_rows,
+      [[self._page_set[0].url, '-', '3'],
+       [self._page_set[1].url, '4', '-']])
+
+