Clean up gclient sync's construction of the set of modified files

gclient_scm.py

 # Copyright (c) 2012 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.
 
 """Gclient-specific SCM-specific operations."""
 
 from __future__ import print_function
 
 import errno
 import logging
@@ skipping 359 matching lines @@
       # Check again for a revision in case an initial ref was specified
       # in the url, for example bla.git@refs/heads/custombranch
       revision = deps_revision
       managed = False
     if not revision:
       revision = default_rev
 
     if managed:
       self._DisableHooks()
 
-    files = [] if file_list is not None else None
-
     printed_path = False
     verbose = []
     if options.verbose:
       self.Print('_____ %s at %s' % (self.relpath, revision), timestamp=False)
       verbose = ['--verbose']
       printed_path = True
 
     remote_ref = scm.GIT.RefToRemoteRef(revision, self.remote)
     if remote_ref:
       # Rewrite remote refs to their local equivalents.
@@ skipping 164 matching lines @@
       if not printed_path:
         self.Print('_____ %s at %s' % (self.relpath, revision), timestamp=False)
     elif current_type == 'hash':
       # case 1
       # Can't find a merge-base since we don't know our upstream. That makes
       # this command VERY likely to produce a rebase failure. For now we
       # assume origin is our upstream since that's what the old behavior was.
       upstream_branch = self.remote
       if options.revision or deps_revision:
         upstream_branch = revision
-      self._AttemptRebase(upstream_branch, files, options,
+      self._AttemptRebase(upstream_branch, file_list, options,
                           printed_path=printed_path, merge=options.merge)
       printed_path = True
     elif rev_type == 'hash':
       # case 2
-      self._AttemptRebase(upstream_branch, files, options,
+      self._AttemptRebase(upstream_branch, file_list, options,
                           newbase=revision, printed_path=printed_path,
                           merge=options.merge)
       printed_path = True
     elif remote_ref and ''.join(remote_ref) != upstream_branch:
       # case 4
       new_base = ''.join(remote_ref)
       if not printed_path:
         self.Print('_____ %s at %s' % (self.relpath, revision), timestamp=False)
       switch_error = ("Could not switch upstream branch from %s to %s\n"
                      % (upstream_branch, new_base) +
@@ skipping 16 matching lines @@
         self.Print("Switching upstream branch from %s to %s" %
                    (upstream_branch, new_base))
         switch_branch = 'gclient_' + remote_ref[1]
         self._Capture(['branch', '-f', switch_branch, new_base])
         self._Checkout(options, switch_branch, force=True, quiet=True)
       else:
         # case 4c
         raise gclient_utils.Error(switch_error)
     else:
       # case 3 - the default case
-      if files is not None:
-        files = self._Capture(['diff', upstream_branch, '--name-only']).split()
+      rebase_files = self._Capture(
+          ['diff', upstream_branch, '--name-only']).split()
       if verbose:
         self.Print('Trying fast-forward merge to branch : %s' % upstream_branch)
       try:
         merge_args = ['merge']
         if options.merge:
           merge_args.append('--ff')
         else:
           merge_args.append('--ff-only')
         merge_args.append(upstream_branch)
         merge_output = self._Capture(merge_args)
       except subprocess2.CalledProcessError as e:
+        rebase_files = []
         if re.match('fatal: Not possible to fast-forward, aborting.', e.stderr):
-          files = []
           if not printed_path:
             self.Print('_____ %s at %s' % (self.relpath, revision),
                        timestamp=False)
             printed_path = True
           while True:
             if not options.auto_rebase:
               try:
                 action = self._AskForData(
                     'Cannot %s, attempt to rebase? '
                     '(y)es / (q)uit / (s)kip : ' %
                         ('merge' if options.merge else 'fast-forward merge'),
                     options)
               except ValueError:
                 raise gclient_utils.Error('Invalid Character')
             if options.auto_rebase or re.match(r'yes|y', action, re.I):
-              self._AttemptRebase(upstream_branch, files, options,
+              self._AttemptRebase(upstream_branch, rebase_files, options,
                                   printed_path=printed_path, merge=False)
               printed_path = True
               break
             elif re.match(r'quit|q', action, re.I):
               raise gclient_utils.Error("Can't fast-forward, please merge or "
                                         "rebase manually.\n"
                                         "cd %s && git " % self.checkout_path
                                         + "rebase %s" % upstream_branch)
             elif re.match(r'skip|s', action, re.I):
               self.Print('Skipping %s' % self.relpath)
@@ skipping 20 matching lines @@
           if not printed_path:
             self.Print('_____ %s at %s' % (self.relpath, revision),
                        timestamp=False)
             printed_path = True
           self.Print(merge_output.strip())
           if not verbose:
             # Make the output a little prettier. It's nice to have some
             # whitespace between projects when syncing.
             self.Print('')
 
-    if file_list is not None:
-      file_list.extend([os.path.join(self.checkout_path, f) for f in files])
+      file_list.extend(
+          [os.path.join(self.checkout_path, f) for f in rebase_files])
 
     # If the rebase generated a conflict, abort and ask user to fix
     if self._IsRebasing():
       raise gclient_utils.Error('\n____ %s at %s\n'
                                 '\nConflict while rebasing this branch.\n'
                                 'Fix the conflict and run gclient again.\n'
                                 'See man git-rebase for details.\n'
                                 % (self.relpath, revision))
 
     if verbose:
@@ skipping 476 matching lines @@
     kwargs.setdefault('cwd', self.checkout_path)
     kwargs.setdefault('stdout', self.out_fh)
     kwargs['filter_fn'] = self.filter
     kwargs.setdefault('print_stdout', False)
     env = scm.GIT.ApplyEnvVars(kwargs)
     cmd = ['git'] + args
     if show_header:
       gclient_utils.CheckCallAndFilterAndHeader(cmd, env=env, **kwargs)
     else:
       gclient_utils.CheckCallAndFilter(cmd, env=env, **kwargs)