Add support for empty files, __init__.py is a common example.

checkout.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.
 """Manages a project checkout.
 
 Includes support for svn, git-svn and git.
 """
 
 from __future__ import with_statement
@@ skipping 109 matching lines @@
           os.remove(filename)
         else:
           dirname = os.path.dirname(p.filename)
           full_dir = os.path.join(self.project_path, dirname)
           if dirname and not os.path.isdir(full_dir):
             os.makedirs(full_dir)
           if p.is_binary:
             with open(os.path.join(filename), 'wb') as f:
               f.write(p.get())
           else:
-            stdout = subprocess2.check_output(
-                ['patch', '-p%s' % p.patchlevel],
-                stdin=p.get(),
-                cwd=self.project_path)
+            if p.diff_hunks:
+              stdout = subprocess2.check_output(
+                  ['patch', '-p%s' % p.patchlevel],
+                  stdin=p.get(),
+                  cwd=self.project_path)
+            elif p.is_new:
+              # There is only a header. Just create the file.
+              open(os.path.join(self.project_path, p.filename), 'w').close()
         for post in post_processor:
           post(self, p)
       except OSError, e:
         raise PatchApplicationFailed(p.filename, '%s%s' % (stdout, e))
       except subprocess.CalledProcessError, e:
         raise PatchApplicationFailed(
             p.filename, '%s%s' % (stdout, getattr(e, 'stdout', None)))
 
   def commit(self, commit_message, user):
     """Stubbed out."""
@@ skipping 107 matching lines @@
     for p in patches:
       try:
         # It is important to use credentials=False otherwise credentials could
         # leak in the error message. Credentials are not necessary here for the
         # following commands anyway.
         stdout = ''
         if p.is_delete:
           stdout += self._check_output_svn(
               ['delete', p.filename, '--force'], credentials=False)
         else:
-          new = not os.path.exists(p.filename)
-
           # svn add while creating directories otherwise svn add on the
           # contained files will silently fail.
           # First, find the root directory that exists.
           dirname = os.path.dirname(p.filename)
           dirs_to_create = []
           while (dirname and
               not os.path.isdir(os.path.join(self.project_path, dirname))):
             dirs_to_create.append(dirname)
             dirname = os.path.dirname(dirname)
           for dir_to_create in reversed(dirs_to_create):
             os.mkdir(os.path.join(self.project_path, dir_to_create))
             stdout += self._check_output_svn(
                 ['add', dir_to_create, '--force'], credentials=False)
 
           if p.is_binary:
             with open(os.path.join(self.project_path, p.filename), 'wb') as f:
               f.write(p.get())
           else:
-            cmd = ['patch', '-p%s' % p.patchlevel, '--forward', '--force']
-            stdout += subprocess2.check_output(
-                cmd, stdin=p.get(), cwd=self.project_path)
-          if new:
+            if p.diff_hunks:
+              cmd = ['patch', '-p%s' % p.patchlevel, '--forward', '--force']
+              stdout += subprocess2.check_output(
+                  cmd, stdin=p.get(), cwd=self.project_path)
+            elif p.is_new:
+              # There is only a header. Just create the file.
+              open(os.path.join(self.project_path, p.filename), 'w').close()
+          if p.is_new:
             stdout += self._check_output_svn(
                 ['add', p.filename, '--force'], credentials=False)
           for prop in p.svn_properties:
             stdout += self._check_output_svn(
                 ['propset', prop[0], prop[1], p.filename], credentials=False)
           for prop, values in self.svn_config.auto_props.iteritems():
             if fnmatch.fnmatch(p.filename, prop):
               for value in values.split(';'):
                 if '=' not in value:
                   params = [value, '*']
@@ skipping 108 matching lines @@
         else:
           dirname = os.path.dirname(p.filename)
           full_dir = os.path.join(self.project_path, dirname)
           if dirname and not os.path.isdir(full_dir):
             os.makedirs(full_dir)
           if p.is_binary:
             with open(os.path.join(self.project_path, p.filename), 'wb') as f:
               f.write(p.get())
             stdout += self._check_output_git(['add', p.filename])
           else:
+            # No need to do anything special with p.is_new or if not
+            # p.diff_hunks. git apply manages all that already.
             stdout += self._check_output_git(
                 ['apply', '--index', '-p%s' % p.patchlevel], stdin=p.get())
           for prop in p.svn_properties:
             # Ignore some known auto-props flags through .subversion/config,
             # bails out on the other ones.
             # TODO(maruel): Read ~/.subversion/config and detect the rules that
             # applies here to figure out if the property will be correctly
             # handled.
             if not prop[0] in ('svn:eol-style', 'svn:executable'):
               raise patch.UnsupportedPatchFormat(
@@ skipping 236 matching lines @@
         user, message))
     return 'FAKE'
 
   @property
   def project_name(self):
     return self.checkout.project_name
 
   @property
   def project_path(self):
     return self.checkout.project_path