Teach mojo_benchmark to produce chart_data for the perf dashboard.

mojo/devtools/common/devtoolslib/perf_dashboard_unittest.py

+# Copyright 2015 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.
+
+"""Tests for the Chromium Performance Dashboard data format implementation."""
+
+import imp
+import json
+import os.path
+import sys
+import unittest
+
+try:
+  imp.find_module("devtoolslib")
+except ImportError:
+  sys.path.append(os.path.dirname(os.path.dirname(os.path.abspath(__file__))))
+
+from devtoolslib.perf_dashboard import ChartDataRecorder
+
+class ChartDataRecorderTest(unittest.TestCase):
+  """Tests the chart data recorder."""
+
+  def test_empty(self):
+    """Tests chart data with no charts."""
+    recorder = ChartDataRecorder()
+    result = json.loads(recorder.get_json())
+    self.assertEquals(0, len(result))
+
+  def test_one_chart(self):
+    """Tests chart data with two samples in one chart."""
+    recorder = ChartDataRecorder()
+    recorder.record_scalar('chart', 'val1', 'ms', 1)
+    recorder.record_scalar('chart', 'val2', 'ms', 2)
+
+    result = json.loads(recorder.get_json())
+    self.assertEquals(1, len(result))

[viettrungluu, 2015/10/15 22:32:56]

This seems like a very long-winded way to test the contents of |result|. Can't
you just compare it with a dictionary?

[ppi, 2015/10/15 23:13:14]

Done.

+    self.assertEquals(2, len(result['chart']))
+    self.assertEquals('scalar', result['chart'][0]['type'])
+    self.assertEquals('val1', result['chart'][0]['name'])
+    self.assertEquals('ms', result['chart'][0]['units'])
+    self.assertEquals(1, result['chart'][0]['value'])
+    self.assertEquals('scalar', result['chart'][1]['type'])
+    self.assertEquals('val2', result['chart'][1]['name'])
+    self.assertEquals('ms', result['chart'][1]['units'])
+    self.assertEquals(2, result['chart'][1]['value'])
+
+  def test_two_charts(self):
+    """Tests chart data with two samples over two charts."""
+    recorder = ChartDataRecorder()
+    recorder.record_scalar('chart1', 'val1', 'ms', 1)
+    recorder.record_scalar('chart2', 'val2', 'ms', 2)
+
+    result = json.loads(recorder.get_json())
+    self.assertEquals(2, len(result))
+    self.assertEquals(1, len(result['chart1']))
+    self.assertEquals(1, len(result['chart2']))
+    self.assertEquals('scalar', result['chart1'][0]['type'])
+    self.assertEquals('val1', result['chart1'][0]['name'])
+    self.assertEquals('ms', result['chart1'][0]['units'])
+    self.assertEquals(1, result['chart1'][0]['value'])
+    self.assertEquals('scalar', result['chart2'][0]['type'])
+    self.assertEquals('val2', result['chart2'][0]['name'])
+    self.assertEquals('ms', result['chart2'][0]['units'])
+    self.assertEquals(2, result['chart2'][0]['value'])