Add automatic is_new=True on git copy or rename.

patch.py

 # coding=utf8
 # Copyright (c) 2011 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.
 """Utility functions to handle patches."""
 
 import posixpath
 import os
 import re
 
@@ skipping 203 matching lines @@
       if old == 'dev/null' and new == 'dev/null':
         self._fail('Unexpected /dev/null git diff.')
       break
 
     if not old or not new:
       self._fail('Unexpected git diff; couldn\'t find git header.')
 
     if old not in (self.filename, 'dev/null'):
       # Copy or rename.
       self.source_filename = old
+      self.is_new = True
 
     last_line = ''
 
     while lines:
       line = lines.pop(0)
       self._verify_git_header_process_line(lines, line, last_line)
       last_line = line
 
     # Cheap check to make sure the file name is at least mentioned in the
     # 'diff' header. That the only remaining invariant.
@@ skipping 34 matching lines @@
       mode = match.group(2)
       # Only look at owner ACL for executable.
       # TODO(maruel): Add support to remove a property.
       if bool(int(mode[4]) & 1):
         self.svn_properties.append(('svn:executable', '*'))
 
     match = re.match(r'^--- (.*)$', line)
     if match:
       if last_line[:3] in ('---', '+++'):
         self._fail('--- and +++ are reversed')
-      self.is_new = match.group(1) == '/dev/null'
-      # TODO(maruel): Use self.source_file.
-      if self.mangle(match.group(1)) not in (old, 'dev/null'):
+      if match.group(1) == '/dev/null':
+        self.is_new = True
+      elif self.mangle(match.group(1)) != old:
+        # git patches are always well formatted, do not allow random filenames.
         self._fail('Unexpected git diff: %s != %s.' % (old, match.group(1)))
       if not lines or not lines[0].startswith('+++'):
         self._fail('Missing git diff output name.')
       return
 
     match = re.match(r'^\+\+\+ (.*)$', line)
     if match:
       if not last_line.startswith('---'):
         self._fail('Unexpected git diff: --- not following +++.')
-      # TODO(maruel): new == self.filename.
       if '/dev/null' == match.group(1):
         self.is_delete = True
       elif self.filename != self.mangle(match.group(1)):
         self._fail(
             'Unexpected git diff: %s != %s.' % (self.filename, match.group(1)))
       if lines:
         self._fail('Crap after +++')
       # We're done.
       return
 
@@ skipping 19 matching lines @@
 
   def _verify_svn_header_process_line(self, lines, line, last_line):
     """Processes a single line of the header.
 
     Returns True if it should continue looping.
     """
     match = re.match(r'^--- ([^\t]+).*$', line)
     if match:
       if last_line[:3] in ('---', '+++'):
         self._fail('--- and +++ are reversed')
-      self.is_new = match.group(1) == '/dev/null'
-      if (self.mangle(match.group(1)) != self.filename and
-           match.group(1) != '/dev/null'):
+      if match.group(1) == '/dev/null':
+        self.is_new = True
+      elif self.mangle(match.group(1)) != self.filename:
+        # guess the source filename.
         self.source_filename = match.group(1)
+        self.is_new = True
       if not lines or not lines[0].startswith('+++'):
         self._fail('Nothing after header.')
       return
 
     match = re.match(r'^\+\+\+ ([^\t]+).*$', line)
     if match:
       if not last_line.startswith('---'):
         self._fail('Unexpected diff: --- not following +++.')
       if match.group(1) == '/dev/null':
         self.is_delete = True
@@ skipping 18 matching lines @@
     for patch in self.patches:
       patch.set_relpath(relpath)
 
   def __iter__(self):
     for patch in self.patches:
       yield patch
 
   @property
   def filenames(self):
     return [p.filename for p in self.patches]