systrace/catapult/common/py_trace_event/py_trace_event/trace_event_impl/perfetto_trace_writer_unittest.py

#!/usr/bin/env python
# Copyright 2019 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 StringIO

from py_trace_event.trace_event_impl import perfetto_trace_writer


class PerfettoTraceWriterTest(unittest.TestCase):
  """ Tests functions that write perfetto protobufs.

  TODO(crbug.com/944078): Switch to using python-protobuf library
  and implement proper protobuf parsing then.
  """


  def testWriteThreadDescriptorEvent(self):
    result = StringIO.StringIO()
    perfetto_trace_writer.write_thread_descriptor_event(
        output=result,
        pid=1,
        tid=2,
        ts=1556716807306000,
    )
    expected_output = (
        '\n\x17P\x80\x80@\xc8\x02\x01\xe2\x02\r\x08\x01\x10'
        '\x020\x90\xf6\xc2\x82\xb6\xfa\xe1\x02'
    )
    self.assertEqual(expected_output, result.getvalue())

  def testWriteTwoEvents(self):
    result = StringIO.StringIO()
    perfetto_trace_writer.write_thread_descriptor_event(
        output=result,
        pid=1,
        tid=2,
        ts=1556716807306000,
    )
    perfetto_trace_writer.write_event(
        output=result,
        ph="M",
        category="category",
        name="event_name",
        ts=1556716807406000,
        args={},
        tid=2,
    )
    expected_output = (
       '\n\x17P\x80\x80@\xc8\x02\x01\xe2\x02\r\x08\x01\x10'
       '\x020\x90\xf6\xc2\x82\xb6\xfa\xe1\x02\n2P\x80\x80@Z\x0c\x08'
       '\xa0\x8d\x06\x18\x012\x04\x08\x01\x10Mb\x1e\n\x0c\x08\x01'
       '\x12\x08category\x12\x0e\x08\x01\x12\nevent_name'
    )
    self.assertEqual(expected_output, result.getvalue())

  def testWriteMetadata(self):
    result = StringIO.StringIO()
    perfetto_trace_writer.write_metadata(
        output=result,
        benchmark_start_time_us=1556716807306000,
        story_run_time_us=1556716807406000,
        benchmark_name="benchmark",
        benchmark_description="description",
        story_name="story",
        story_tags=["foo", "bar"],
        story_run_index=0,
        label="label",
        had_failures=False,
    )
    expected_output = (
        '\nI\x82\x03F\x08\x90\xf6\xc2\x82\xb6\xfa\xe1'
        '\x02\x10\xb0\x83\xc9\x82\xb6\xfa\xe1\x02\x1a\tbenchmark"'
        '\x0bdescription*\x05label2\x05story:\x03foo:\x03bar@\x00H\x00'
    )
    self.assertEqual(expected_output, result.getvalue())