Add 'repo selfupdate' to upgrade only repo

Users may want to upgrade only repo to the latest release, but
leave their working tree state alone and avoid 'repo sync'.

Signed-off-by: Shawn O. Pearce <sop@google.com>

subcmds/selfupdate.py

@@ -0,0 +1,59 @@
+#
+# Copyright (C) 2009 The Android Open Source Project
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+from optparse import SUPPRESS_HELP
+import sys
+
+from command import Command, MirrorSafeCommand
+from subcmds.sync import _PostRepoUpgrade
+from subcmds.sync import _PostRepoFetch
+
+class Selfupdate(Command, MirrorSafeCommand):
+  common = False
+  helpSummary = "Update repo to the latest version"
+  helpUsage = """
+%prog
+"""
+  helpDescription = """
+The '%prog' command upgrades repo to the latest version, if a
+newer version is available.
+
+Normally this is done automatically by 'repo sync' and does not
+need to be performed by an end-user.
+"""
+
+  def _Options(self, p):
+    p.add_option('--no-repo-verify',
+                 dest='no_repo_verify', action='store_true',
+                 help='do not verify repo source code')
+    p.add_option('--repo-upgraded',
+                 dest='repo_upgraded', action='store_true',
+                 help=SUPPRESS_HELP)
+
+  def Execute(self, opt, args):
+    rp = self.manifest.repoProject
+    rp.PreSync()
+
+    if opt.repo_upgraded:
+      _PostRepoUpgrade(self.manifest)
+
+    else:
+      if not rp.Sync_NetworkHalf():
+        print >>sys.stderr, "error: can't update repo"
+        sys.exit(1)
+
+      _PostRepoFetch(rp,
+                     no_repo_verify = opt.no_repo_verify,
+                     verbose = True)