[Predator] renamed "Result" to "Suspect"

appengine/findit/crash/results.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 collections import namedtuple
-
-
-# TODO(wrengr): we should change things to use integers with None as
-# \"infinity\", rather than using floats.
-# TODO(http://crbug.com/644476): this class needs a better name.
-class AnalysisInfo(namedtuple('AnalysisInfo',
-    ['min_distance', 'min_distance_frame'])):
-  __slots__ = ()
-
-  def __str__(self): # pragma: no cover
-    return ('AnalysisInfo(min_distance = %d, min_distance_frame = %s)'
-        % (self.min_distance, self.min_distance_frame))
-
-
-# TODO(wrengr): it's not clear why the ``priority`` is stored at all,
-# given that every use in this file discards it. ``Result.file_to_stack_infos``
-# should just store pointers directly to the frames themselves rather
-# than needing this intermediate object.
-# TODO(http://crbug.com/644476): this class needs a better name.
-class StackInfo(namedtuple('StackInfo', ['frame', 'priority'])):
-  """Pair of a frame and the ``priority`` of the ``CallStack`` it came from."""
-  __slots__ = ()
-
-  def __str__(self): # pragma: no cover
-    return 'StackInfo(frame = %s, priority = %f)' % (self.frame, self.priority)
-
-
-# TODO(http://crbug.com/644476): this class needs a better name.
-class Result(object):
-  """Represents findit culprit result."""
-
-  def __init__(self, changelog, dep_path,
-               confidence=None, reasons=None, changed_files=None):
-    assert isinstance(confidence, (int, float, type(None))), TypeError(
-        'In the ``confidence`` argument to the Result constructor, '
-        'expected a number or None, but got a %s object instead.'
-        % confidence.__class__.__name__)
-    self.changelog = changelog
-    self.dep_path = dep_path
-    self.confidence = None if confidence is None else float(confidence)
-    self.reasons = reasons
-    self.changed_files = changed_files
-
-    # TODO(wrengr): (a) make these two fields private/readonly
-    # TODO(wrengr): (b) zip them together.
-    self.file_to_stack_infos = {}
-    self.file_to_analysis_info = {}
-
-  def ToDict(self):
-    return {
-        'url': self.changelog.commit_url,
-        'review_url': self.changelog.code_review_url,
-        'revision': self.changelog.revision,
-        'project_path': self.dep_path,
-        'author': self.changelog.author_email,
-        'time': str(self.changelog.author_time),
-        'reasons': self.reasons,
-        'changed_files': self.changed_files,
-        'confidence': self.confidence,
-    }
-
-  # TODO(katesonia): This is unusable for logging because in all the
-  # cases that need logging it returns the empty string! We should print
-  # this out in a more useful way (e.g., how CrashConfig is printed)
-  # so that callers don't have to use ``str(result.ToDict())`` instead. If
-  # we want a method that does what this one does, we should give it a
-  # different name that indicates what it's actually printing out.
-  def ToString(self):
-    if not self.file_to_stack_infos:
-      return ''
-
-    lines = []
-    for file_path, stack_infos in self.file_to_stack_infos.iteritems():
-      line_parts = []
-      for frame, _ in stack_infos:
-        line_parts.append('frame #%d' % frame.index)
-
-      lines.append('Changed file %s crashed in %s' % (
-          file_path, ', '.join(line_parts)))
-
-    return '\n'.join(lines)
-
-  def __str__(self):
-    return self.ToString()
-
-
-class MatchResult(Result):
-  """Represents findit culprit result got from match algorithm."""
-
-  def Update(self, file_path, stack_infos, blame):
-    """Updates a match result with file path and its stack_infos and blame.
-
-    When a file_path is found both shown in stacktrace and touched by
-    the revision of this result, update result with the information of
-    this file.
-
-    Inserts the file path and its stack infos, and updates the min distance
-    if less distance is found between touched lines of this result and
-    crashed lines in the file path.
-
-    Args:
-      file_path (str): File path of the crashed file.
-      stack_infos (list of StackInfo): List of the frames of this file
-        together with their callstack priorities.
-      blame (Blame): Blame oject of this file.
-    """
-    self.file_to_stack_infos[file_path] = stack_infos
-
-    if not blame:
-      return
-
-    min_distance = float('inf')
-    min_distance_frame = stack_infos[0][0]
-    for region in blame:
-      if region.revision != self.changelog.revision:
-        continue
-
-      region_start = region.start
-      region_end = region_start + region.count - 1
-      for frame, _ in stack_infos:
-        frame_start = frame.crashed_line_numbers[0]
-        frame_end = frame.crashed_line_numbers[-1]
-        distance = _DistanceBetweenLineRanges((frame_start, frame_end),
-                                              (region_start, region_end))
-        if distance < min_distance:
-          min_distance = distance
-          min_distance_frame = frame
-
-    self.file_to_analysis_info[file_path] = AnalysisInfo(
-        min_distance = min_distance,
-        min_distance_frame = min_distance_frame,
-    )
-
-
-def _DistanceBetweenLineRanges((start1, end1), (start2, end2)):
-  """Given two ranges, compute the (unsigned) distance between them.
-
-  Args:
-    start1: the start of the first range
-    end1: the end of the first range. Must be greater than start1.
-    start2: the start of the second range
-    end2: the end of the second range. Must be greater than start2.
-
-  Returns:
-    If the end of the earlier range comes before the start of the later
-    range, then the difference between those points. Otherwise, returns
-    zero (because the ranges overlap)."""
-  assert end1 >= start1, ValueError(
-      'the first range is empty: %d < %d' % (end1, start1))
-  assert end2 >= start2, ValueError(
-      'the second range is empty: %d < %d' % (end2, start2))
-  # There are six possible cases, but in all the cases where the two
-  # ranges overlap, the latter two differences will be negative.
-  return max(0, start2 - end1, start1 - end2)
-
-
-class MatchResults(dict):
-  """A map from revisions to the MatchResult object for that revision."""
-
-  def __init__(self, ignore_cls=None):
-    super(MatchResults, self).__init__()
-    self._ignore_cls = ignore_cls
-
-  def GenerateMatchResults(self, file_path, dep_path,
-                           stack_infos, changelogs, blame):
-    """Compute match results from a list of CLs, and store them.
-
-    Match results are generated based on newly found file path, its stack_infos,
-    and all the changelogs that touched this file in the dep in regression
-    ranges, those reverted changelogs should be ignored.
-
-    Args:
-      file_path (str): File path of the crashed file.
-      dep_path (str): Path of the dependency of the file.
-      stack_infos (list): List of stack_info dicts, represents frames of this
-        file and the callstack priorities of those frames.
-      changelogs (list): List of Changelog objects in the dep in regression
-        range which touched the file.
-      blame (Blame): Blame of the file.
-    """
-    for changelog in changelogs:
-      if self._ignore_cls and changelog.revision in self._ignore_cls:
-        continue
-
-      if changelog.revision not in self:
-        self[changelog.revision] = MatchResult(changelog, dep_path)
-
-      match_result = self[changelog.revision]
-      match_result.Update(file_path, stack_infos, blame)