[DO NOT COMMIT] Refactor systrace to support new clock sync design

systrace/systrace/systrace_unittest.py

Index: systrace/systrace/systrace_unittest.py
diff --git a/systrace/systrace/systrace_unittest.py b/systrace/systrace/systrace_unittest.py
new file mode 100755
index 0000000000000000000000000000000000000000..54b8c51eb292c596e24b48e380bbea553ffc23e4
--- /dev/null
+++ b/systrace/systrace/systrace_unittest.py
@@ -0,0 +1,127 @@
+#!/usr/bin/env python
+
+# Copyright (c) 2016 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
+import logging
+from systrace import tracing_controller
+from systrace.tracing_agents import TracingAgent, TraceResults
+
+from collections import namedtuple
+
+tmout = namedtuple('tmout', ['timeout', 'collection_timeout'])
+base_tmout = tmout(10, 30)
+
+class FakeTracingAgent(TracingAgent):
+  def __init__(self, name, clock_sync=True):
+    super(FakeTracingAgent, self).__init__()
+    self._name = name
+    self._clock_sync = clock_sync
+    self._sync_seen = False
+  def StartAgentTracing(self, options, categories, timeout=10):
+    # pylint: disable=unused-variable
+    # options, categories variables not used in test, but we still
+    # need to have them to match the interface
+    return True
+  def StopAgentTracing(self, timeout=10):
+    return True
+  def GetResults(self, timeout=30):
+    return TraceResults(self._name,
+                        'Sync' if self._sync_seen else 'NoSync')
+  def SupportsExplicitClockSync(self):
+    return self._clock_sync
+  def RecordClockSyncMarker(self, sync_id, callback):
+    if not self._clock_sync:
+      raise NotImplementedError
+    self._sync_seen = True
+    callback(1.0, sync_id)
+
+def _GetSyncCount(controller):
+  result = 0
+  for x in controller.GetResults().trace_data:
+    if x['name'] == 'clock_sync':
+      result += 1
+  return result
+
+class SystraceTest(unittest.TestCase):
+
+  def testStartTracing(self):
+    cont = tracing_controller.TracingController(base_tmout, None, [])
+    self.assertFalse(cont.trace_in_progress)
+    cont.StartTracing()
+    self.assertTrue(cont.trace_in_progress)
+    cont.StopTracing()
+
+  def testStopFirst(self):
+    cont = tracing_controller.TracingController(base_tmout, None, [])
+    self.assertRaises(AssertionError, cont.StopTracing)
+
+  def testDoubleStart(self):
+    cont = tracing_controller.TracingController(base_tmout, None, [])
+    cont.StartTracing()
+    self.assertRaises(AssertionError, cont.StartTracing)
+    cont.StopTracing()
+
+  def testDoubleStop(self):
+    cont = tracing_controller.TracingController(base_tmout, None, [])
+    cont.StartTracing()
+    cont.StopTracing()
+    self.assertRaises(AssertionError, cont.StopTracing)
+
+  def testNoAgents(self):
+    cont = tracing_controller.TracingController(base_tmout, None, [])
+    cont.StartTracing()
+    cont.StopTracing()
+    self.assertEqual(_GetSyncCount(cont), 0)
+
+  def testNoSupportedAgents(self):
+    cont = tracing_controller.TracingController(base_tmout, None,
+                                                [FakeTracingAgent('1', False)])
+    cont.StartTracing()
+    cont.StopTracing()
+    self.assertEqual(_GetSyncCount(cont), 0)
+
+  def testOneSupportedAgent(self):
+    cont = tracing_controller.TracingController(base_tmout, None,
+                                                [FakeTracingAgent('1', False),
+                                                 FakeTracingAgent('2', True)])
+    cont.StartTracing()
+    cont.StopTracing()
+    self.assertEqual(_GetSyncCount(cont), 1)
+
+  def testTwoSupportedAgents(self):
+    cont = tracing_controller.TracingController(base_tmout, None,
+                                                [FakeTracingAgent('1', True),
+                                                 FakeTracingAgent('2', False),
+                                                 FakeTracingAgent('3', True)])
+    cont.StartTracing()
+    cont.StopTracing()
+    self.assertEqual(_GetSyncCount(cont), 2)
+
+  def testOutputs(self):
+    cont = tracing_controller.TracingController(base_tmout, None,
+                                                [FakeTracingAgent('1', True),
+                                                 FakeTracingAgent('2', False),
+                                                 FakeTracingAgent('3', True)])
+    cont.StartTracing()
+    cont.StopTracing()
+    results = cont._all_results
+    self.assertEqual(results['1'], 'Sync')
+    self.assertEqual(results['2'], 'NoSync')
+    self.assertEqual(results['3'], 'Sync')
+
+  def testMultipleSyncCycles(self):
+    cont = tracing_controller.TracingController(base_tmout, None,
+                                                [FakeTracingAgent('1', True),
+                                                 FakeTracingAgent('2', False),
+                                                 FakeTracingAgent('3', True)])
+    cont.StartTracing()
+    cont._IssueClockSyncMarker()
+    cont.StopTracing()
+    self.assertEqual(_GetSyncCount(cont), 4)
+
+if __name__ == "__main__":
+  logging.getLogger().setLevel(logging.DEBUG)
+  unittest.main(verbosity=2)