Update chromite to match the changes in chromiumos's git server.

Review URL: http://codereview.chromium.org/6286160

git-svn-id: svn://svn.chromium.org/chrome/trunk/tools/depot_tools@74182 0039d316-1c4b-4281-b951-d872f2087c98

chromite

@@ -20,58 +20,55 @@ here:
   http://git.chromium.org/gitweb/?p=chromite.git;a=blob;f=bin/chromite
 
 Since this script is _copied_, it should remain small and not use internal libs.
+
 """
 
 # Python imports.
 import os
 import sys
 
-if __name__ == '__main__':
-  # Look relative to CROS_WORKON_SRCROOT if that variable exists.  This is
-  # the "inside the chroot" case.
-  if 'CROS_WORKON_SRCROOT' in os.environ:
-    chromite_path = os.path.join(os.environ['CROS_WORKON_SRCROOT'],
-                                 'chromite', 'shell', 'main.py')
-    if os.path.isfile(chromite_path):
-      # Exec the script, which will never return.
-      os.execv(chromite_path, sys.argv)
-    else:
-      print (
-          "ERROR: Couldn't find the chromite tool.\n"
-          "\n"
-          "You may need to update your chroot.  If you need help, see:\n"
-          "  http://www.chromium.org/chromium-os/developer-guide"
-      )
-      sys.exit(1)
+def Search(path):
+  """Return an iterator of lists of places to look for chromite."""
 
-  # Outside the chroot, search upward until the "parent" dir doesn't change
-  # (on Linux, that means we're at '/').  That is an error case.
-  dir = os.getcwd()
-  prev_dir = None
-  while dir != prev_dir:
-    chromite_path = os.path.join(dir, 'chromite', 'shell', 'main.py')
-    if os.path.isfile(chromite_path):
-      # Add the directory above chromite to PYTHONPATH before executing, so
-      # that "import chromite.abc.xyz" works...
-      env = os.environ.copy()
-      if 'PYTHONPATH' in env:
-        env['PYTHONPATH'] += ':%s' % dir
-      else:
-        env['PYTHONPATH'] = dir
+  if os.path.exists('/etc/debian_chroot'):
+    # We're in the chroot.  Chromite should be in the python path inside the
+    # chroot, so we don't do any searching.  NOTE that we purposely don't want
+    # CROS_WORKON_SRCROOT in the python path.
+    yield []
+  else:
+    # Look in $CROS_WORKON_SRCROOT first.  The idea is that a user would set
+    # this manually if they wanted to specify a particular version of chromite.
+    if 'CROS_WORKON_SRCROOT' in os.environ:
+      yield [os.environ['CROS_WORKON_SRCROOT']]
 
-      # Exec the script, which will never return.
-      os.execve(chromite_path, sys.argv, env)
+    # Search upward until we either end up with a blank dir or the "parent" dir
+    # doesn't change.
+    prev_path = None
+    while path and path != prev_path:
+      yield [path]
+      path, prev_path = os.path.dirname(path), path
 
-    prev_dir = dir
-    dir = os.path.dirname(dir)
 
+for path in Search(os.getcwd()):
+  sys.path = path + sys.path
+  try:
+    import chromite.shell.main
+    break
+  except ImportError, e:
+    # We've got different modules named chromite in the tree, pulling in the
+    # wrong one will break the right one.  So unload it.
+    if 'chromite' in sys.modules:
+      del sys.modules['chromite']
+    sys.path = sys.path[len(path):]
+else:
   # TODO(dianders): Should we actually print out the 'repo init' call that
   # the user should use?
-  print (
+  sys.stderr.write(
       "ERROR: Couldn't find the chromite tool.\n"
       "\n"
       "Please change to a directory inside your Chromium OS source tree\n"
       "and retry.  If you need to setup a Chromium OS source tree, see:\n"
-      "  http://www.chromium.org/chromium-os/developer-guide"
-  )
+      "  http://www.chromium.org/chromium-os/developer-guide\n")
   sys.exit(1)
+
+chromite.shell.main.main()