cpplint: Pull in upstream changes

The changes include:
- root flag now can process non-subdirectories
-- https://github.com/google/styleguide/commit/e7ddd2af622475b0c5e0f587d69fb061d2c10c46

- root flag can be configured with CPPLINT.cfg
-- https://github.com/google/styleguide/commit/2322e4ffaa19f4c55e5679102318ce67454fb7ed

- root setting is relative to the CPPLINT.cfg file
-- https://github.com/google/styleguide/commit/8a87a46cc7f8d6cca5c0203ddba5d81149db7695

- Cleans up header file detection for hpp and hxx

- Adds quite mode

Bug: 852898

Change-Id: Id44bbfadc913cc27192049ab9a222f22d0deab5d
Reviewed-on: https://chromium-review.googlesource.com/1108381
Commit-Queue: Amin Hassani <ahassani@chromium.org>
Reviewed-by: Aaron Gable <agable@chromium.org>
diff --git a/cpplint.py b/cpplint.py
index 42e3da3..f919562 100755
--- a/cpplint.py
+++ b/cpplint.py
@@ -53,12 +53,19 @@
 import string
 import sys
 import unicodedata
+import sysconfig
+
+try:
+  xrange          # Python 2
+except NameError:
+  xrange = range  # Python 3
 
 
 _USAGE = """
 Syntax: cpplint.py [--verbose=#] [--output=vs7] [--filter=-x,+y,...]
                    [--counting=total|toplevel|detailed] [--root=subdir]
-                   [--linelength=digits]
+                   [--linelength=digits] [--headers=x,y,...]
+                   [--quiet]
         <file> [file] ...
 
   The style guidelines this tries to follow are those in
@@ -85,6 +92,9 @@
     verbose=#
       Specify a number 0-5 to restrict errors to certain verbosity levels.
 
+    quiet
+      Don't print anything if no errors are found.
+
     filter=-x,+y,...
       Specify a comma-separated list of category-filters to apply: only
       error messages whose category names pass the filters will be printed.
@@ -116,12 +126,13 @@
       ignored.
 
       Examples:
-        Assuming that src/.git exists, the header guard CPP variables for
-        src/chrome/browser/ui/browser.h are:
+        Assuming that top/src/.git exists (and cwd=top/src), the header guard
+        CPP variables for top/src/chrome/browser/ui/browser.h are:
 
         No flag => CHROME_BROWSER_UI_BROWSER_H_
         --root=chrome => BROWSER_UI_BROWSER_H_
         --root=chrome/browser => UI_BROWSER_H_
+        --root=.. => SRC_CHROME_BROWSER_UI_BROWSER_H_
 
     linelength=digits
       This is the allowed line length for the project. The default value is
@@ -136,6 +147,14 @@
       Examples:
         --extensions=hpp,cpp
 
+    headers=x,y,...
+      The header extensions that cpplint will treat as .h in checks. Values are
+      automatically added to --extensions list.
+
+      Examples:
+        --headers=hpp,hxx
+        --headers=hpp
+
     cpplint.py supports per-directory configurations specified in CPPLINT.cfg
     files. CPPLINT.cfg file can contain a number of key=value pairs.
     Currently the following options are supported:
@@ -144,6 +163,8 @@
       filter=+filter1,-filter2,...
       exclude_files=regex
       linelength=80
+      root=subdir
+      headers=x,y,...
 
     "set noparent" option prevents cpplint from traversing directory tree
     upwards looking for more .cfg files in parent directories. This option
@@ -159,6 +180,12 @@
 
     "linelength" allows to specify the allowed line length for the project.
 
+    The "root" option is similar in function to the --root flag (see example
+    above). Paths are relative to the directory of the CPPLINT.cfg.
+
+    The "headers" option is similar in function to the --headers flag
+    (see example above).
+
     CPPLINT.cfg has an effect on files in the same directory and all
     sub-directories, unless overridden by a nested configuration file.
 
@@ -525,10 +552,7 @@
 # The root directory used for deriving header guard CPP variable.
 # This is set by --root flag.
 _root = None
-
-# The project root directory. Used for deriving header guard CPP variable.
-# This is set by --project_root flag. Must be an absolute path.
-_project_root = None
+_root_debug = False
 
 # The allowed line length of files.
 # This is set by --linelength flag.
@@ -538,10 +562,25 @@
 # This is set by --extensions flag.
 _valid_extensions = set(['cc', 'h', 'cpp', 'cu', 'cuh'])
 
+# Treat all headers starting with 'h' equally: .h, .hpp, .hxx etc.
+# This is set by --headers flag.
+_hpp_headers = set(['h'])
+
 # {str, bool}: a map from error categories to booleans which indicate if the
 # category should be suppressed for every line.
 _global_error_suppressions = {}
 
+def ProcessHppHeadersOption(val):
+  global _hpp_headers
+  try:
+    _hpp_headers = set(val.split(','))
+    # Automatically append to extensions list so it does not have to be set 2 times
+    _valid_extensions.update(_hpp_headers)
+  except ValueError:
+    PrintUsage('Header extensions must be comma separated list.')
+
+def IsHeaderExtension(file_extension):
+  return file_extension in _hpp_headers
 
 def ParseNolintSuppressions(filename, raw_line, linenum, error):
   """Updates the global list of line error-suppressions.
@@ -834,6 +873,7 @@
     self._filters_backup = self.filters[:]
     self.counting = 'total'  # In what way are we counting errors?
     self.errors_by_category = {}  # string to int dict storing error counts
+    self.quiet = False  # Suppress non-error messagess?
 
     # output format:
     # "emacs" - format that emacs can parse (default)
@@ -844,6 +884,12 @@
     """Sets the output format for errors."""
     self.output_format = output_format
 
+  def SetQuiet(self, quiet):
+    """Sets the module's quiet settings, and returns the previous setting."""
+    last_quiet = self.quiet
+    self.quiet = quiet
+    return last_quiet
+
   def SetVerboseLevel(self, level):
     """Sets the module's verbosity, and returns the previous setting."""
     last_verbose_level = self.verbose_level
@@ -911,7 +957,7 @@
     for category, count in self.errors_by_category.iteritems():
       sys.stderr.write('Category \'%s\' errors found: %d\n' %
                        (category, count))
-    sys.stderr.write('Total errors found: %d\n' % self.error_count)
+    sys.stdout.write('Total errors found: %d\n' % self.error_count)
 
 _cpplint_state = _CppLintState()
 
@@ -925,6 +971,14 @@
   """Sets the module's output format."""
   _cpplint_state.SetOutputFormat(output_format)
 
+def _Quiet():
+  """Return's the module's quiet setting."""
+  return _cpplint_state.quiet
+
+def _SetQuiet(quiet):
+  """Set the module's quiet status, and return previous setting."""
+  return _cpplint_state.SetQuiet(quiet)
+
 
 def _VerboseLevel():
   """Returns the module's verbosity setting."""
@@ -1071,10 +1125,6 @@
     if os.path.exists(fullname):
       project_dir = os.path.dirname(fullname)
 
-      if _project_root:
-        prefix = os.path.commonprefix([_project_root, project_dir])
-        return fullname[len(prefix) + 1:]
-
       if os.path.exists(os.path.join(project_dir, ".svn")):
         # If there's a .svn file in the current directory, we recursively look
         # up the directory tree for the top of the SVN checkout
@@ -1089,12 +1139,13 @@
 
       # Not SVN <= 1.6? Try to find a git, hg, or svn top level directory by
       # searching up from the current path.
-      root_dir = os.path.dirname(fullname)
-      while (root_dir != os.path.dirname(root_dir) and
-             not os.path.exists(os.path.join(root_dir, ".git")) and
-             not os.path.exists(os.path.join(root_dir, ".hg")) and
-             not os.path.exists(os.path.join(root_dir, ".svn"))):
-        root_dir = os.path.dirname(root_dir)
+      root_dir = current_dir = os.path.dirname(fullname)
+      while current_dir != os.path.dirname(current_dir):
+        if (os.path.exists(os.path.join(current_dir, ".git")) or
+            os.path.exists(os.path.join(current_dir, ".hg")) or
+            os.path.exists(os.path.join(current_dir, ".svn"))):
+          root_dir = current_dir
+        current_dir = os.path.dirname(current_dir)
 
       if (os.path.exists(os.path.join(root_dir, ".git")) or
           os.path.exists(os.path.join(root_dir, ".hg")) or
@@ -1189,8 +1240,8 @@
   if _ShouldPrintError(category, confidence, linenum):
     _cpplint_state.IncrementErrorCount(category)
     if _cpplint_state.output_format == 'vs7':
-      sys.stderr.write('%s(%s):  %s  [%s] [%d]\n' % (
-          filename, linenum, message, category, confidence))
+      sys.stderr.write('%s(%s): error cpplint: [%s] %s [%d]\n' % (
+          filename, linenum, category, message, confidence))
     elif _cpplint_state.output_format == 'eclipse':
       sys.stderr.write('%s:%s: warning: %s  [%s] [%d]\n' % (
           filename, linenum, message, category, confidence))
@@ -1732,6 +1783,30 @@
   else:
     return 0
 
+def PathSplitToList(path):
+  """Returns the path split into a list by the separator.
+
+  Args:
+    path: An absolute or relative path (e.g. '/a/b/c/' or '../a')
+
+  Returns:
+    A list of path components (e.g. ['a', 'b', 'c]).
+  """
+  lst = []
+  while True:
+    (head, tail) = os.path.split(path)
+    if head == path: # absolute paths end
+      lst.append(head)
+      break
+    if tail == path: # relative paths end
+      lst.append(tail)
+      break
+
+    path = head
+    lst.append(tail)
+
+  lst.reverse()
+  return lst
 
 def GetHeaderGuardCPPVariable(filename):
   """Returns the CPP variable that should be used as a header guard.
@@ -1754,8 +1829,58 @@
 
   fileinfo = FileInfo(filename)
   file_path_from_root = fileinfo.RepositoryName()
-  if _root:
-    file_path_from_root = re.sub('^' + _root + os.sep, '', file_path_from_root)
+
+  def FixupPathFromRoot():
+    if _root_debug:
+      sys.stderr.write("\n_root fixup, _root = '%s', repository name = '%s'\n"
+          %(_root, fileinfo.RepositoryName()))
+
+    # Process the file path with the --root flag if it was set.
+    if not _root:
+      if _root_debug:
+        sys.stderr.write("_root unspecified\n")
+      return file_path_from_root
+
+    def StripListPrefix(lst, prefix):
+      # f(['x', 'y'], ['w, z']) -> None  (not a valid prefix)
+      if lst[:len(prefix)] != prefix:
+        return None
+      # f(['a, 'b', 'c', 'd'], ['a', 'b']) -> ['c', 'd']
+      return lst[(len(prefix)):]
+
+    # root behavior:
+    #   --root=subdir , lstrips subdir from the header guard
+    maybe_path = StripListPrefix(PathSplitToList(file_path_from_root),
+                                 PathSplitToList(_root))
+
+    if _root_debug:
+      sys.stderr.write(("_root lstrip (maybe_path=%s, file_path_from_root=%s," +
+          " _root=%s)\n") %(maybe_path, file_path_from_root, _root))
+
+    if maybe_path:
+      return os.path.join(*maybe_path)
+
+    #   --root=.. , will prepend the outer directory to the header guard
+    full_path = fileinfo.FullName()
+    root_abspath = os.path.abspath(_root)
+
+    maybe_path = StripListPrefix(PathSplitToList(full_path),
+                                 PathSplitToList(root_abspath))
+
+    if _root_debug:
+      sys.stderr.write(("_root prepend (maybe_path=%s, full_path=%s, " +
+          "root_abspath=%s)\n") %(maybe_path, full_path, root_abspath))
+
+    if maybe_path:
+      return os.path.join(*maybe_path)
+
+    if _root_debug:
+      sys.stderr.write("_root ignore, returning %s\n" %(file_path_from_root))
+
+    #   --root=FAKE_DIR is ignored
+    return file_path_from_root
+
+  file_path_from_root = FixupPathFromRoot()
   return re.sub(r'[^a-zA-Z0-9]', '_', file_path_from_root).upper() + '_'
 
 
@@ -3864,6 +3989,14 @@
       # outputting warnings for the matching closing brace, if there are
       # nested blocks with trailing semicolons, we will get the error
       # messages in reversed order.
+
+      # We need to check the line forward for NOLINT
+      raw_lines = clean_lines.raw_lines
+      ParseNolintSuppressions(filename, raw_lines[endlinenum-1], endlinenum-1,
+                              error)
+      ParseNolintSuppressions(filename, raw_lines[endlinenum], endlinenum,
+                              error)
+
       error(filename, endlinenum, 'readability/braces', 4,
             "You don't need a ; after a }")
 
@@ -4161,6 +4294,16 @@
       if unicodedata.east_asian_width(uc) in ('W', 'F'):
         width += 2
       elif not unicodedata.combining(uc):
+        # Issue 337
+        # https://mail.python.org/pipermail/python-list/2012-August/628809.html
+        if (sys.version_info.major, sys.version_info.minor) <= (3, 2):
+          # https://github.com/python/cpython/blob/2.7/Include/unicodeobject.h#L81
+          is_wide_build = sysconfig.get_config_var("Py_UNICODE_SIZE") >= 4
+          # https://github.com/python/cpython/blob/2.7/Objects/unicodeobject.c#L564
+          is_low_surrogate = 0xDC00 <= ord(uc) <= 0xDFFF
+          if not is_wide_build and is_low_surrogate:
+            width -= 1
+
         width += 1
     return width
   else:
@@ -4234,7 +4377,7 @@
 
   # Check if the line is a header guard.
   is_header_guard = False
-  if file_extension == 'h':
+  if IsHeaderExtension(file_extension):
     cppvar = GetHeaderGuardCPPVariable(filename)
     if (line.startswith('#ifndef %s' % cppvar) or
         line.startswith('#define %s' % cppvar) or
@@ -4583,7 +4726,7 @@
   CheckGlobalStatic(filename, clean_lines, linenum, error)
   CheckPrintf(filename, clean_lines, linenum, error)
 
-  if file_extension == 'h':
+  if IsHeaderExtension(file_extension):
     # TODO(unknown): check that 1-arg constructors are explicit.
     #                How to tell it's a constructor?
     #                (handled in CheckForNonStandardConstructs for now)
@@ -4690,12 +4833,12 @@
   # Check for use of unnamed namespaces in header files.  Registration
   # macros are typically OK, so we allow use of "namespace {" on lines
   # that end with backslashes.
-  if (file_extension == 'h'
+  if (IsHeaderExtension(file_extension)
       and Search(r'\bnamespace\s*{', line)
       and line[-1] != '\\'):
     error(filename, linenum, 'build/namespaces', 4,
           'Do not use unnamed namespaces in header files.  See '
-          'https://google.github.io/styleguide/cppguide.html#Namespaces'
+          'https://google-styleguide.googlecode.com/svn/trunk/cppguide.xml#Namespaces'
           ' for more information.')
 
 
@@ -5780,7 +5923,7 @@
   RemoveMultiLineComments(filename, lines, error)
   clean_lines = CleansedLines(lines)
 
-  if file_extension == 'h':
+  if IsHeaderExtension(file_extension):
     CheckForHeaderGuard(filename, clean_lines, error)
 
   for line in xrange(clean_lines.NumLines()):
@@ -5849,6 +5992,9 @@
             if base_name:
               pattern = re.compile(val)
               if pattern.match(base_name):
+                if _cpplint_state.quiet:
+                  # Suppress "Ignoring file" warning when using --quiet.
+                  return False
                 sys.stderr.write('Ignoring "%s": file excluded by "%s". '
                                  'File path component "%s" matches '
                                  'pattern "%s"\n' %
@@ -5860,6 +6006,12 @@
                 _line_length = int(val)
             except ValueError:
                 sys.stderr.write('Line length must be numeric.')
+          elif name == 'root':
+            global _root
+            # root directories are specified relative to CPPLINT.cfg dir.
+            _root = os.path.join(os.path.dirname(cfg_file), val)
+          elif name == 'headers':
+            ProcessHppHeadersOption(val)
           else:
             sys.stderr.write(
                 'Invalid configuration option (%s) in file %s\n' %
@@ -5894,6 +6046,7 @@
 
   _SetVerboseLevel(vlevel)
   _BackupFilters()
+  old_errors = _cpplint_state.error_count
 
   if not ProcessConfigOverrides(filename):
     _RestoreFilters()
@@ -5962,7 +6115,10 @@
         Error(filename, linenum, 'whitespace/newline', 1,
               'Unexpected \\r (^M) found; better to use only \\n')
 
-  sys.stderr.write('Done processing %s\n' % filename)
+  # Suppress printing anything if --quiet was passed unless the error
+  # count has increased after processing this file.
+  if not _cpplint_state.quiet or old_errors != _cpplint_state.error_count:
+    sys.stdout.write('Done processing %s\n' % filename)
   _RestoreFilters()
 
 
@@ -6006,13 +6162,15 @@
                                                  'root=',
                                                  'linelength=',
                                                  'extensions=',
-                                                 'project_root='])
+                                                 'headers=',
+                                                 'quiet'])
   except getopt.GetoptError:
     PrintUsage('Invalid arguments.')
 
   verbosity = _VerboseLevel()
   output_format = _OutputFormat()
   filters = ''
+  quiet = _Quiet()
   counting_style = ''
 
   for (opt, val) in opts:
@@ -6022,6 +6180,8 @@
       if val not in ('emacs', 'vs7', 'eclipse'):
         PrintUsage('The only allowed output formats are emacs, vs7 and eclipse.')
       output_format = val
+    elif opt == '--quiet':
+      quiet = True
     elif opt == '--verbose':
       verbosity = int(val)
     elif opt == '--filter':
@@ -6035,11 +6195,6 @@
     elif opt == '--root':
       global _root
       _root = val
-    elif opt == '--project_root':
-      global _project_root
-      _project_root = val
-      if not os.path.isabs(_project_root):
-        PrintUsage('Project root must be an absolute path.')
     elif opt == '--linelength':
       global _line_length
       try:
@@ -6052,11 +6207,14 @@
           _valid_extensions = set(val.split(','))
       except ValueError:
           PrintUsage('Extensions must be comma separated list.')
+    elif opt == '--headers':
+      ProcessHppHeadersOption(val)
 
   if not filenames:
     PrintUsage('No files were specified.')
 
   _SetOutputFormat(output_format)
+  _SetQuiet(quiet)
   _SetVerboseLevel(verbosity)
   _SetFilters(filters)
   _SetCountingStyle(counting_style)
@@ -6077,7 +6235,9 @@
   _cpplint_state.ResetErrorCounts()
   for filename in filenames:
     ProcessFile(filename, _cpplint_state.verbose_level)
-  _cpplint_state.PrintErrorCounts()
+  # If --quiet is passed, suppress printing error count unless there are errors.
+  if not _cpplint_state.quiet or _cpplint_state.error_count > 0:
+    _cpplint_state.PrintErrorCounts()
 
   sys.exit(_cpplint_state.error_count > 0)