appengine/predator/analysis/test/occurrence_test.py

# Copyright 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.

from analysis.analysis_testcase import AnalysisTestCase
from analysis.occurrence import Occurrence
from analysis.occurrence import DefaultOccurrenceRanking
from analysis.occurrence import RankByOccurrence
from analysis.stacktrace import StackFrame
from analysis.stacktrace import CallStack
from analysis.suspect import Suspect
from gae_libs.pipeline_wrapper import pipeline_handlers


class DummyClassifier(object):

  def GetClassFromStackFrame(self, frame):
    if frame.dep_path == 'src/':
      return 'class_1'

    if frame.dep_path == 'dummy/':
      return None

    return 'class_2'

  def GetClassFromSuspect(self, _result):  # pragma: no cover.
    return 'class_3'

  def Classify(self, results, crash_stack):
    top_n_frames = 4
    if results:
      classes = map(self.GetClassFromSuspect, results[:top_n_frames])
    else:
      classes = map(self.GetClassFromStackFrame,
          crash_stack.frames[:top_n_frames])

    class_list = RankByOccurrence(classes, 1)
    if class_list:
      return class_list[0]

    return ''


class ClassifierTest(AnalysisTestCase):

  def testDefaultOccurrenceRanking(self):
    self.assertEqual(DefaultOccurrenceRanking(Occurrence('c1', [0])),
        (-1, 0))
    self.assertEqual(DefaultOccurrenceRanking(Occurrence('c1', [0, 1])),
        (-float('inf'), 0))

  def testClassifyCrashStack(self):
    dummy_classifier = DummyClassifier()

    crash_stack = CallStack(0)
    self.assertEqual(dummy_classifier.Classify([], crash_stack), '')

    crash_stack = CallStack(0, frame_list=[
        StackFrame(0, 'src/', 'a::c(p* &d)', 'f0.cc', 'src/f0.cc', [177]),
        StackFrame(1, 'src/', 'a::d(a* c)', 'f1.cc', 'src/f1.cc', [227]),
        StackFrame(2, 'src/dummy', 'a::e(int)', 'f2.cc', 'src/f2.cc', [87]),
        StackFrame(3, 'dummy/', 'a::g(int)', 'f3.cc', 'src/f3.cc', [87])])

    self.assertEqual(dummy_classifier.Classify([], crash_stack), 'class_1')

    crash_stack = CallStack(0, frame_list=[
        StackFrame(0, 'src/', 'a::c(p* &d)', 'f0.cc', 'src/f0.cc', [177]),
        StackFrame(1, 'src/dummy', 'a::d(a* c)', 'f1.cc', 'src/f1.cc', [227]),
        StackFrame(2, 'src/dummy', 'a::e(int)', 'f2.cc', 'src/f2.cc', [87])])

    self.assertEqual(dummy_classifier.Classify([], crash_stack), 'class_2')

  def testClassifySuspects(self):
    dummy_classifier = DummyClassifier()

    suspect = Suspect(self.GetDummyChangeLog(), 'src/')
    suspect.file_to_stack_infos = {
        'f0.cc': [(StackFrame(
            0, 'src/', 'a::c(p* &d)', 'f0.cc', 'src/f0.cc', [177]), 0)]
    }

    self.assertEqual(dummy_classifier.Classify([suspect], CallStack(0)),
                     'class_3')