gclient_scm: add test for unsupported scm

gclient_scm.py

 # Copyright 2009 Google Inc.  All Rights Reserved.
 #
 # 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.
 
 
 import os
 import re
 import subprocess
 import sys
 import xml.dom.minidom
 
 import gclient_utils
 
 SVN_COMMAND = "svn"
 
 
 ### SCM abstraction layer
 
 
+# Factory Method for SCM wrapper creation
+
+def CreateSCM(url=None, root_dir=None, relpath=None, scm_name='svn'):
+  # TODO(maruel): Deduce the SCM from the url.
+  scm_map = {
+    'svn' : SVNWrapper,
+  }
+  if not scm_name in scm_map:
+    raise gclient_utils.Error('Unsupported scm %s' % scm_name)
+  return scm_map[scm_name](url, root_dir, relpath, scm_name)
+
+
+# SCMWrapper base class
+
 class SCMWrapper(object):
   """Add necessary glue between all the supported SCM.
 
   This is the abstraction layer to bind to different SCM. Since currently only
   subversion is supported, a lot of subersionism remains. This can be sorted out
   once another SCM is supported."""
   def __init__(self, url=None, root_dir=None, relpath=None,
                scm_name='svn'):
-    # TODO(maruel): Deduce the SCM from the url.
     self.scm_name = scm_name
     self.url = url
     self._root_dir = root_dir
     if self._root_dir:
       self._root_dir = self._root_dir.replace('/', os.sep)
     self.relpath = relpath
     if self.relpath:
       self.relpath = self.relpath.replace('/', os.sep)
 
   def FullUrlForRelativeUrl(self, url):
     # Find the forth '/' and strip from there. A bit hackish.
     return '/'.join(self.url.split('/')[:4]) + url
 
   def RunCommand(self, command, options, args, file_list=None):
     # file_list will have all files that are modified appended to it.
     if file_list is None:
       file_list = []
 
-    commands = {
-      'cleanup':  self.cleanup,
-      'export':   self.export,
-      'update':   self.update,
-      'revert':   self.revert,
-      'status':   self.status,
-      'diff':     self.diff,
-      'pack':     self.pack,
-      'runhooks': self.status,
-    }
+    commands = ['cleanup', 'export', 'update', 'revert',
+                'status', 'diff', 'pack', 'runhooks']
 
     if not command in commands:
       raise gclient_utils.Error('Unknown command %s' % command)
 
-    return commands[command](options, args, file_list)
+    if not command in dir(self):
+      raise gclient_utils.Error('Command %s not implemnted in %s wrapper' % (
+          command, self.scm_name))
+
+    return getattr(self, command)(options, args, file_list)
+
+
+class SVNWrapper(SCMWrapper):
+  """ Wrapper for SVN """
 
   def cleanup(self, options, args, file_list):
     """Cleanup working copy."""
     command = ['cleanup']
     command.extend(args)
     RunSVN(command, os.path.join(self._root_dir, self.relpath))
 
   def diff(self, options, args, file_list):
     # NOTE: This function does not currently modify file_list.
     command = ['diff']
@@ skipping 169 matching lines @@
                  os.path.join(self._root_dir, self.relpath))
           accumulated_paths = [p]
           accumulated_length = len(p)
         else:
           accumulated_paths.append(p)
           accumulated_length += len(p)
       if accumulated_paths:
         RunSVN(command + accumulated_paths,
                os.path.join(self._root_dir, self.relpath))
 
+  def runhooks(self, options, args, file_list):
+    self.status(options, args, file_list)
+
   def status(self, options, args, file_list):
     """Display status information."""
     path = os.path.join(self._root_dir, self.relpath)
     command = ['status']
     command.extend(args)
     if not os.path.isdir(path):
       # svn status won't work if the directory doesn't exist.
       print("\n________ couldn't run \'%s\' in \'%s\':\nThe directory "
             "does not exist."
             % (' '.join(command), path))
@@ skipping 297 matching lines @@
                           xml_props_status)
         # Col 2
         if wc_status[0].getAttribute('wc-locked') == 'true':
           statuses[2] = 'L'
         # Col 3
         if wc_status[0].getAttribute('copied') == 'true':
           statuses[3] = '+'
         item = (''.join(statuses), file)
         results.append(item)
   return results