Add a --keep-going flag for people who run rebase-update infrequently.

tests/git_rebase_update_test.py

 #!/usr/bin/env python
 # Copyright 2014 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.
 
 """Unit tests for git_rebase_update.py"""
 
 import os
 import sys
 
@@ skipping 241 matching lines @@
     self.repo.git('checkout', '--theirs', 'M')
     self.repo.git('rebase', '--skip')
 
     output, _ = self.repo.capture_stdio(self.reup.main)
     self.assertIn('Failed! Attempting to squash', output)
     self.assertIn('Deleted branch branch_G', output)
     self.assertIn('Deleted branch branch_L', output)
     self.assertIn('\'branch_G\' was merged', output)
     self.assertIn('checking out \'origin/master\'', output)
 
+  def testRebaseConflictsKeepGoing(self):
+    # Pretend that branch_L landed
+    self.origin.git('checkout', 'master')
+    with self.origin.open('L', 'w') as f:
+      f.write('L')
+    self.origin.git('add', 'L')
+    self.origin.git_commit('L')
+
+    # Add a commit to branch_K so that things fail
+    self.repo.git('checkout', 'branch_K')
+    with self.repo.open('M', 'w') as f:
+      f.write('NOPE')
+    self.repo.git('add', 'M')
+    self.repo.git_commit('K NOPE')
+
+    # Add a commits to branch_L which will work when squashed
+    self.repo.git('checkout', 'branch_L')
+    self.repo.git('reset', 'branch_L~')
+    with self.repo.open('L', 'w') as f:
+      f.write('NOPE')
+    self.repo.git('add', 'L')
+    self.repo.git_commit('L NOPE')
+    with self.repo.open('L', 'w') as f:
+      f.write('L')
+    self.repo.git('add', 'L')
+    self.repo.git_commit('L YUP')
+
+    # start on a branch which will be deleted
+    self.repo.git('checkout', 'branch_G')
+
+    self.repo.git('config', 'branch.branch_K.dormant', 'false')
+    output, _ = self.repo.capture_stdio(self.reup.main, ['-k'])
+    self.assertIn('--keep-going set, continuing with next branch.', output)
+    self.assertIn('could not be cleanly rebased:', output)
+    self.assertIn('  branch_K', output)
+
 
   def testTrackTag(self):
     self.origin.git('tag', 'lkgr', self.origin['M'])
     self.repo.git('tag', 'lkgr', self.repo['D'])
 
     self.repo.git('config', 'branch.branch_G.remote', '.')
     self.repo.git('config', 'branch.branch_G.merge', 'refs/tags/lkgr')
 
     self.assertIn(
         'fatal: \'foo bar\' is not a valid branch name',
@@ skipping 64 matching lines @@
     """)
 
 
 if __name__ == '__main__':
   sys.exit(coverage_utils.covered_main((
     os.path.join(DEPOT_TOOLS_ROOT, 'git_rebase_update.py'),
     os.path.join(DEPOT_TOOLS_ROOT, 'git_new_branch.py'),
     os.path.join(DEPOT_TOOLS_ROOT, 'git_reparent_branch.py'),
     os.path.join(DEPOT_TOOLS_ROOT, 'git_rename_branch.py')
   )))