[Findit] Improve output format and cherry-pick bugs fix.

1. For DEPS file parsing, switching from svn to git.

2. For output of testcase https://cluster-fuzz.appspot.com/testcase?key=5097237064450048, now it is:

Lines 1103-1112 of file ThreadState.cpp which potentially caused crash are changed in this cl (frame #2, function "blink::ThreadState::performPendingSweep()").

Lines 1120-1136, 1170-1174 of file Heap.cpp which potentially caused crash are changed in this cl (frame #0, function "blink::ThreadHeap<blink::FinalizedHeapObjectHeader>::sweepNormalPages(blink::HeapStats*)"; frame #1, function "blink::ThreadHeap<blink::FinalizedHeapObjectHeader>::sweep(blink::HeapStats*)").
Minimum distance from crashed line to changed line: 0. (File: ThreadState.cpp, Crashed on: 1100, Changed: 1100).

NOTRY=true

Review URL: https://codereview.chromium.org/504443004

Cr-Commit-Position: refs/heads/master@{#291987}

8 files changed, 199 insertions, 101 deletions

diff --git a/tools/findit/chromium_deps.py b/tools/findit/chromium_deps.py
index e2b0b7c..97d31cf 100644
--- a/tools/findit/chromium_deps.py
+++ b/tools/findit/chromium_deps.py
@@ -66,20 +66,29 @@ def _GetComponentName(path, host_dirs):
   return '_'.join(path.split('/'))
 
 
-def _GetContentOfDEPS(url, retries=5, sleep_time=0.1):
+def _GetContentOfDEPS(revision, retries=5, sleep_time=0.1):
+  chromium_git_file_url_template = CONFIG['chromium_git_file_url']
+
+  deps_file_name = '.DEPS.git'
   count = 0
   while True:
     count += 1
-    try:
-      _, content = utils.GetHttpClient().Get(url, timeout=60)
-      return content
-
-    # TODO(jeun): Handle HTTP Errors, such as 404.
-    except urllib2.HTTPError:
-      if count < retries:
-        time.sleep(sleep_time)
-      else:
-        break
+
+    url = chromium_git_file_url_template % (revision, deps_file_name)
+    http_status_code, content = utils.GetHttpClient().Get(url, timeout=60)
+
+    if http_status_code == 404 and deps_file_name != 'DEPS':
+      deps_file_name = 'DEPS'
+      count = 0
+      continue
+    elif http_status_code == 200:
+      # Googlesource git returns text file encoded in base64, so decode it.
+      return base64.b64decode(content)
+
+    if count < retries:
+      time.sleep(sleep_time)
+    else:
+      break
 
   return ''
 
@@ -90,7 +99,7 @@ def GetChromiumComponents(chromium_revision,
   """Return a list of components used by Chrome of the given revision.
 
   Args:
-    chromium_revision: The revision of the Chrome build.
+    chromium_revision: Revision of the Chrome build: svn revision, or git hash.
     os_platform: The target platform of the Chrome build, eg. win, mac, etc.
     deps_file_downloader: A function that takes the chromium_revision as input,
                           and returns the content of the DEPS file. The returned
@@ -104,23 +113,21 @@ def GetChromiumComponents(chromium_revision,
   if os_platform.lower() == 'linux':
     os_platform = 'unix'
 
-  git_base_url = CONFIG['git_base_url']
-  git_deps_path = CONFIG['git_deps_path']
-  svn_base_url = CONFIG['svn_base_url']
-  svn_deps_path = CONFIG['svn_deps_path']
-  svn_src_chromium_url = CONFIG['svn_src_chromium_url']
-  is_git_hash = utils.IsGitHash(chromium_revision)
-  if is_git_hash:
-    url = git_base_url + (git_deps_path % chromium_revision)
-  else:
-    url = svn_base_url + (svn_deps_path % chromium_revision)
+  chromium_git_base_url = CONFIG['chromium_git_base_url']
 
-  # Download the content of DEPS file in chromium.
-  deps_content = deps_file_downloader(url)
+  if not utils.IsGitHash(chromium_revision):
+    # Convert svn revision or commit position to Git hash.
+    cr_rev_url_template = CONFIG['cr_rev_url']
+    url = cr_rev_url_template % chromium_revision
+    # TODO(stgao): Add retry in HttpClient.
+    _, content = utils.GetHttpClient().Get(url, timeout=60)
+    cr_rev_data = json.loads(content)
+    if 'git_sha' not in cr_rev_data:
+      raise Exception('Failed to convert svn revision to git hash')
+    chromium_revision = cr_rev_data['git_sha']
 
-  # Googlesource git returns text file encoded in base64, so decode it.
-  if is_git_hash:
-    deps_content = base64.b64decode(deps_content)
+  # Download the content of DEPS file in chromium.
+  deps_content = deps_file_downloader(chromium_revision)
 
   all_deps = {}
 
@@ -133,16 +140,14 @@ def GetChromiumComponents(chromium_revision,
   # Figure out components based on the dependencies.
   components = {}
   host_dirs = CONFIG['host_directories']
-  for component_path in all_deps:
+  for component_path, component_repo_url in all_deps.iteritems():
+    if component_repo_url is None:
+      # For some platform like iso, some component is ignored.
+      continue
+
     name = _GetComponentName(component_path, host_dirs)
-    repository, revision = all_deps[component_path].split('@')
+    repository, revision = component_repo_url.split('@')
     is_git_hash = utils.IsGitHash(revision)
-    if repository.startswith('/'):
-      # In DEPS file, if a path starts with /, it is a relative path to the
-      # https://src.chromium.org/chrome. Strip /trunk at the end of the base
-      # url and add it to the base url.
-      # TODO(stgao): Use git repo after chromium moves to git.
-      repository = svn_src_chromium_url + repository
     if is_git_hash:
       repository_type = 'git'
     else:
@@ -157,19 +162,12 @@ def GetChromiumComponents(chromium_revision,
         'revision': revision
     }
 
-  # Add chromium as a component, depending on the repository type.
-  if is_git_hash:
-    repository = git_base_url
-    repository_type = 'git'
-  else:
-    repository = svn_base_url
-    repository_type = 'svn'
-
+  # Add chromium as a component.
   components['src/'] = {
       'path': 'src/',
       'name': 'chromium',
-      'repository': repository,
-      'repository_type': repository_type,
+      'repository': chromium_git_base_url,
+      'repository_type': 'git',
       'revision': chromium_revision
   }
 
diff --git a/tools/findit/chromium_deps_unittest.py b/tools/findit/chromium_deps_unittest.py
index a26ac9c..7f64a12 100644
--- a/tools/findit/chromium_deps_unittest.py
+++ b/tools/findit/chromium_deps_unittest.py
@@ -5,6 +5,7 @@
 import unittest
 
 import chromium_deps
+from common import utils
 
 
 class ChromiumDEPSTest(unittest.TestCase):
@@ -38,12 +39,13 @@ deps_os = {
 
   def testGetChromiumComponents(self):
     chromium_revision = '283296'
+    chromium_revision_git_hash = 'b041fda2e8493dcb26aac08deb493943df240cbb'
     webkit_revision = '178200'
     breakpad_revision = '1345'
     liblouis_commit_hashcode = '3c2daee56250162e5a75830871601d74328d39f5'
 
     def _GetContentOfDEPS(chromium_revision_tmp):
-      self.assertEqual(chromium_revision_tmp, chromium_revision)
+      self.assertEqual(chromium_revision_tmp, chromium_revision_git_hash)
       return self.DEPS_TEMPLATE % (webkit_revision, breakpad_revision,
                                    liblouis_commit_hashcode)
 
@@ -65,10 +67,10 @@ deps_os = {
         },
         'src/': {
             'path': 'src/',
-            'repository_type': 'svn',
+            'repository_type': 'git',
             'name': 'chromium',
-            'repository': 'https://src.chromium.org/chrome/trunk',
-            'revision': chromium_revision
+            'repository': 'https://chromium.googlesource.com/chromium/src/',
+            'revision': chromium_revision_git_hash
         },
         'src/third_party/WebKit/': {
             'path': 'src/third_party/WebKit/',
@@ -85,22 +87,24 @@ deps_os = {
 
   def testGetChromiumComponentRange(self):
     chromium_revision1 = '283200'
+    chromium_revision_git_hash1 = 'c53c387f46a2ff0cf7c072222b826cff0817a80f'
     webkit_revision1 = '178084'
     breakpad_revision1 = '1345'
     liblouis_commit_hashcode1 = '3c2daee56250162e5a75830871601d74328d39f5'
 
     chromium_revision2 = '283296'
+    chromium_revision_git_hash2 = 'b041fda2e8493dcb26aac08deb493943df240cbb'
     webkit_revision2 = '178200'
     breakpad_revision2 = '1345'
     liblouis_commit_hashcode2 = '3c2daee56250162e5a75830871601d74328d39f5'
 
     def _GetContentOfDEPS(chromium_revision):
       chromium_revision = str(chromium_revision)
-      if chromium_revision == chromium_revision1:
+      if chromium_revision == chromium_revision_git_hash1:
         return self.DEPS_TEMPLATE % (webkit_revision1, breakpad_revision1,
                                      liblouis_commit_hashcode1)
       else:
-        self.assertEqual(chromium_revision2, chromium_revision)
+        self.assertEqual(chromium_revision, chromium_revision_git_hash2)
         return self.DEPS_TEMPLATE % (webkit_revision2, breakpad_revision2,
                                      liblouis_commit_hashcode2)
 
@@ -125,13 +129,13 @@ deps_os = {
             'repository_type': 'git'
         },
         'src/': {
-            'old_revision': chromium_revision1,
+            'old_revision': chromium_revision_git_hash1,
             'name': 'chromium',
-            'repository': 'https://src.chromium.org/chrome/trunk',
+            'repository': 'https://chromium.googlesource.com/chromium/src/',
             'rolled': True,
-            'new_revision': chromium_revision2,
+            'new_revision': chromium_revision_git_hash2,
             'path': 'src/',
-            'repository_type': 'svn'
+            'repository_type': 'git'
         },
         'src/third_party/WebKit/': {
             'old_revision': webkit_revision1,
@@ -149,6 +153,37 @@ deps_os = {
         deps_file_downloader=_GetContentOfDEPS)
     self.assertEqual(expected_results, components)
 
+  def _VerifyGitHashForAllComponents(self, deps):
+    self.assertTrue(deps)
+    self.assertTrue(isinstance(deps, dict))
+    for component in deps.values():
+      for key in ['revision', 'old_revision', 'new_revision']:
+        if key in component:
+          self.assertTrue(utils.IsGitHash(component[key]))
+
+  def testComponentRangeCrossGitMigrationPoint(self):
+    # The old revision is from svn.
+    # The new revision is from git.
+    deps = chromium_deps.GetChromiumComponentRange(
+        '291440',
+        '744746cc51ef81c8f8d727fafa46b14d1c03fe44')
+    self._VerifyGitHashForAllComponents(deps)
+
   def testGetSvnRevision(self):
+    # For this case, svn revision needs converting to git hash and there will be
+    # .DEPS.git and DEPS.
     deps = chromium_deps.GetChromiumComponents(284750)
-    self.assertTrue(isinstance(deps, dict))
+    self._VerifyGitHashForAllComponents(deps)
+
+  def testGetGitRevisionWithoutDEPS_dot_GIT(self):
+    # For this case, there is only DEPS, not .DEPS.git.
+    deps = chromium_deps.GetChromiumComponents(
+        'f8b3fe9660d8dda318800f55d5e29799bbfd43f7')
+    self._VerifyGitHashForAllComponents(deps)
+
+
+  def testGetGitRevisionWithDEPS_dot_GIT(self):
+    # For this case, there will be .DEPS.git.
+    deps = chromium_deps.GetChromiumComponents(
+        '8ae88241aa9f224e8ce97250f32469d616e437aa')
+    self._VerifyGitHashForAllComponents(deps)
diff --git a/tools/findit/common/http_client_local.py b/tools/findit/common/http_client_local.py
index bf386f9..fccb0b6 100644
--- a/tools/findit/common/http_client_local.py
+++ b/tools/findit/common/http_client_local.py
@@ -205,11 +205,20 @@ def _SendRequest(url, timeout=None):
         urllib2.HTTPCookieProcessor(cookielib.MozillaCookieJar(cookie_file)))
 
   url_opener = urllib2.build_opener(*handlers)
-  if timeout is not None:
+
+  status_code = None
+  content = None
+
+  try:
     response = url_opener.open(url, timeout=timeout)
-  else:
-    response = url_opener.open(url)
-  return response.code, response.read()
+
+    status_code = response.code
+    content = response.read()
+  except urllib2.HTTPError as e:
+    status_code = e.code
+    content = None
+
+  return status_code, content
 
 
 class HttpClientLocal(http_client.HttpClient):
diff --git a/tools/findit/common/utils.py b/tools/findit/common/utils.py
index 363048c..5011e76 100644
--- a/tools/findit/common/utils.py
+++ b/tools/findit/common/utils.py
@@ -29,3 +29,40 @@ def IsGitHash(revision):
 def GetHttpClient():
   # TODO(stgao): return implementation for appengine when running on appengine.
   return HttpClientLocal
+
+
+def JoinLineNumbers(line_numbers, accepted_gap=1):
+  """Join line numbers into line blocks.
+
+  Args:
+    line_numbers: a list of line number.
+    accepted_gap: if two line numbers are within the give gap,
+                  they would be combined together into a block.
+                  Eg: for (1, 2, 3, 6, 7, 8, 12), if |accepted_gap| = 1, result
+                  would be 1-3, 6-8, 12; if |accepted_gap| = 3, result would be
+                  1-8, 12; if |accepted_gap| =4, result would be 1-12.
+  """
+  if not line_numbers:
+    return ''
+
+  line_numbers = map(int, line_numbers)
+  line_numbers.sort()
+
+  block = []
+  start_line_number = line_numbers[0]
+  last_line_number = start_line_number
+  for current_line_number in line_numbers[1:]:
+    if last_line_number + accepted_gap < current_line_number:
+      if start_line_number == last_line_number:
+        block.append('%d' % start_line_number)
+      else:
+        block.append('%d-%d' % (start_line_number, last_line_number))
+      start_line_number = current_line_number
+    last_line_number = current_line_number
+  else:
+    if start_line_number == last_line_number:
+      block.append('%d' % start_line_number)
+    else:
+      block.append('%d-%d' % (start_line_number, last_line_number))
+
+  return ', '.join(block)
diff --git a/tools/findit/crash_utils.py b/tools/findit/crash_utils.py
index 65ff729..da3c081 100644
--- a/tools/findit/crash_utils.py
+++ b/tools/findit/crash_utils.py
@@ -108,7 +108,7 @@ def NormalizePath(path, parsed_deps):
     repository is not supported, i.e from googlecode.
   """
   # First normalize the path by retreiving the normalized path.
-  normalized_path = os.path.normpath(path.replace('\\', '/'))
+  normalized_path = os.path.normpath(path).replace('\\', '/')
 
   # Iterate through all component paths in the parsed DEPS, in the decreasing
   # order of the length of the file path.
@@ -230,14 +230,19 @@ def GetDataFromURL(url, retries=10, sleep_time=0.1, timeout=5):
     count += 1
     # Retrieves data from URL.
     try:
-      _, data = utils.GetHttpClient().Get(url, timeout=timeout)
-      return data
+      status_code, data = utils.GetHttpClient().Get(url, timeout=timeout)
     except IOError:
-      if count < retries:
-        # If retrieval fails, try after sleep_time second.
-        time.sleep(sleep_time)
-      else:
-        break
+      status_code = -1
+      data = None
+
+    if status_code == 200:
+      return data
+
+    if count < retries:
+      # If retrieval fails, try after sleep_time second.
+      time.sleep(sleep_time)
+    else:
+      break
 
   # Return None if it fails to read data from URL 'retries' times.
   return None
@@ -349,16 +354,24 @@ def AddHyperlink(text, link):
   return '<a href="%s">%s</a>' % (sanitized_link, sanitized_text)
 
 
-def PrettifyList(l):
+def PrettifyList(items):
   """Returns a string representation of a list.
 
   It adds comma in between the elements and removes the brackets.
   Args:
-    l: A list to prettify.
+    items: A list to prettify.
   Returns:
     A string representation of the list.
   """
-  return str(l)[1:-1]
+  return ', '.join(map(str, items))
+
+
+def PrettifyFrameInfo(frame_indices, functions):
+  """Return a string to represent the frames with functions."""
+  frames = []
+  for frame_index, function in zip(frame_indices, functions):
+    frames.append('frame #%s, function "%s"' % (frame_index, function))
+  return '; '.join(frames)
 
 
 def PrettifyFiles(file_list):
diff --git a/tools/findit/deps_config.json b/tools/findit/deps_config.json
index 203202b..57b41f9 100644
--- a/tools/findit/deps_config.json
+++ b/tools/findit/deps_config.json
@@ -1,16 +1,17 @@
 {
-"svn_base_url": "https://src.chromium.org/chrome/trunk/",
-"svn_deps_path": "src/DEPS?p=%s",
-"git_base_url": "https://chromium.googlesource.com/chromium/src/",
-"git_deps_path": "+/%s/DEPS?format=text",
-"svn_src_chromium_url": "https://src.chromium.org/chrome",
-"host_directories": ["src/chrome/browser/resources/",
-                     "src/chrome/test/data/layout_tests/",
-                     "src/media/",
-                     "src/sdch/",
-                     "src/testing/",
-                     "src/third_party/WebKit/",
-                     "src/third_party/",
-                     "src/tools/",
-                     "src/"]
-}
\ No newline at end of file
+  "cr_rev_url": "https://cr-rev.appspot.com/_ah/api/crrev/v1/redirect/%s",
+  "chromium_git_base_url": "https://chromium.googlesource.com/chromium/src/",
+  "chromium_git_file_url":
+      "https://chromium.googlesource.com/chromium/src/+/%s/%s?format=text",
+  "host_directories": [
+      "src/chrome/browser/resources/",
+      "src/chrome/test/data/layout_tests/",
+      "src/media/",
+      "src/sdch/",
+      "src/testing/",
+      "src/third_party/WebKit/",
+      "src/third_party/",
+      "src/tools/",
+      "src/"
+  ]
+}
diff --git a/tools/findit/findit_for_crash.py b/tools/findit/findit_for_crash.py
index c12d6b8..50f12d8 100644
--- a/tools/findit/findit_for_crash.py
+++ b/tools/findit/findit_for_crash.py
@@ -456,13 +456,11 @@ def GenerateReasonForMatches(matches):
                                 for lines in crashed_line_numbers
                                 for crashed_line_number in lines]
         reason.append(
-            'Line %s of file %s which potentially caused the crash '
-            'according to the stacktrace, is changed in this cl'
-            ' (From stack frame %s, function %s).' %
-            (crash_utils.PrettifyList(crashed_line_numbers),
+            'Lines %s of file %s which potentially caused crash '
+            'are changed in this cl (%s).\n' %
+            (utils.JoinLineNumbers(crashed_line_numbers, accepted_gap=4),
              file_name,
-             crash_utils.PrettifyList(stack_frame_indices),
-             crash_utils.PrettifyList(function_list)))
+             crash_utils.PrettifyFrameInfo(stack_frame_indices, function_list)))
 
       else:
         # Get all the files that are not line change.
@@ -479,9 +477,8 @@ def GenerateReasonForMatches(matches):
         pretty_file_names = crash_utils.PrettifyList(file_names)
 
         # Add the reason, break because we took care of the rest of the files.
-        file_string += ('(From stack frames %s, functions %s)' %
-                        (crash_utils.PrettifyList(stack_frame_indices),
-                         crash_utils.PrettifyList(function_list)))
+        file_string += '(%s)' % crash_utils.PrettifyFrameInfo(
+            stack_frame_indices, function_list)
         reason.append(file_string % pretty_file_names)
         break
 
@@ -525,8 +522,8 @@ def CombineMatches(matches):
     if match.min_distance_info:
       file_name, min_crashed_line, min_changed_line = match.min_distance_info
       match.reason += \
-          ('\nMininimum distance from crashed line to changed line: %d. '
-           '(File: %s, Crashed on: %d, Changed: %d).' %
+          ('Minimum distance from crashed line to changed line: %d. '
+           '(File: %s, Crashed on: %d, Changed: %d).\n' %
            (match.min_distance, file_name, min_crashed_line, min_changed_line))
 
   return combined_matches
diff --git a/tools/findit/git_repository_parser.py b/tools/findit/git_repository_parser.py
index d4564f8..d875c26 100644
--- a/tools/findit/git_repository_parser.py
+++ b/tools/findit/git_repository_parser.py
@@ -11,11 +11,18 @@ from repository_parser_interface import ParserInterface
 
 FILE_CHANGE_TYPE_MAP = {
     'add': 'A',
+    'copy': 'C',
     'delete': 'D',
-    'modify': 'M'
+    'modify': 'M',
+    'rename': 'R'
 }
 
 
+def _ConvertToFileChangeType(file_action):
+  # TODO(stgao): verify impact on code that checks the file change type.
+  return file_action[0].upper()
+
+
 class GitParser(ParserInterface):
   """Parser for Git repository in googlesource.
 
@@ -103,7 +110,7 @@ class GitParser(ParserInterface):
             0].getAttribute('class')
 
         # Normalize file action so that it is same as SVN parser.
-        file_change_type = FILE_CHANGE_TYPE_MAP[file_change_type]
+        file_change_type = _ConvertToFileChangeType(file_change_type)
 
         # Add the changed file to the map.
         if file_path not in file_to_revision_map:
@@ -185,7 +192,7 @@ class GitParser(ParserInterface):
       file_change_type = diff['type']
 
       # Normalize file action so that it fits with svn_repository_parser.
-      file_change_type = FILE_CHANGE_TYPE_MAP[file_change_type]
+      file_change_type = _ConvertToFileChangeType(file_change_type)
 
       # Add the file to the map.
       if file_path not in file_to_revision_map:
@@ -204,7 +211,8 @@ class GitParser(ParserInterface):
     backup_url = (base_url + self.url_parts_map['revision_url']) % githash
 
     # If the file is added (not modified), treat it as if it is not changed.
-    if file_change_type == 'A':
+    if file_change_type in ('A', 'C', 'R'):
+      # TODO(stgao): Maybe return whole file change for Add, Rename, and Copy?
       return (backup_url, changed_line_numbers, changed_line_contents)
 
     # Retrieves the diff data from URL, and if it fails, return emptry lines.