First CL for removing our dependency on the checked-in binary for building

editor/build/build.py

 #!/usr/bin/env python
 #
 # Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 # for details. All rights reserved. Use of this source code is governed by a
 # BSD-style license that can be found in the LICENSE file.
 
 import glob
+import gsutil
+import hashlib
+import imp
 import optparse
 import os
 import re
 import shutil
 import subprocess
 import sys
 import tempfile
-import gsutil
 import ziputils
-import hashlib
 
 from os.path import join
 
 BUILD_OS = None
 DART_PATH = None
 TOOLS_PATH = None
 
 GSU_PATH_REV = None
 GSU_PATH_LATEST = None
 GSU_API_DOCS_PATH = None
 GSU_API_DOCS_BUCKET = 'gs://dartlang-api-docs'
 
 REVISION = None
 TRUNK_BUILD = None
 MILESTONE_BUILD = None
 PLUGINS_BUILD = None
 
 NO_UPLOAD = None
 
-utils = None
+def GetUtils():
+  '''Dynamically load the tools/utils.py python module.'''
+  dart_dir = os.path.abspath(os.path.join(__file__, '..', '..', '..'))
+  return imp.load_source('utils', os.path.join(dart_dir, 'tools', 'utils.py'))
+
+utils = GetUtils()
 
 class AntWrapper(object):
   """A wrapper for ant build invocations"""
 
   _antpath = None
   _bzippath = None
   _propertyfile = None
 
   def __init__(self, propertyfile, antpath='/usr/bin', bzippath=None):
     """Initialize the ant path.
@@ skipping 116 matching lines @@
                     help='builder name.',
                     action='store')
   result.add_option('-o', '--out',
                     help='Output Directory.',
                     action='store')
   result.add_option('--dest',
                     help='Output Directory.',
                     action='store')
   return result
 
-
-def GetUtils(toolspath):
-  """Dynamically get the utils module.
-
-  We use a dynamic import for tools/util.py because we derive its location
-  dynamically using sys.argv[0]. This allows us to run this script from
-  different directories.
-
-  Args:
-    toolspath: the path to the tools directory
-
-  Returns:
-    the utils module
-  """
-  global utils
-  sys.path.append(os.path.abspath(toolspath))
-  utils = __import__('utils')
-  return utils
-
-
 def main():
   """Main entry point for the build program."""
   global BUILD_OS
   global DART_PATH
   global TOOLS_PATH
   global GSU_PATH_REV
   global GSU_API_DOCS_PATH
   global GSU_PATH_LATEST
   global REVISION
   global TRUNK_BUILD
   global MILESTONE_BUILD
   global PLUGINS_BUILD
   global NO_UPLOAD
-  global utils
 
   if not sys.argv:
     print 'Script pathname not known, giving up.'
     return 1
 
   scriptdir = os.path.abspath(os.path.dirname(sys.argv[0]))
   editorpath = os.path.abspath(os.path.join(scriptdir, '..'))
   thirdpartypath = os.path.abspath(os.path.join(scriptdir, '..', '..',
                                                 'third_party'))
   toolspath = os.path.abspath(os.path.join(scriptdir, '..', '..',
                                            'tools'))
   dartpath = os.path.abspath(os.path.join(scriptdir, '..', '..'))
   antpath = os.path.join(thirdpartypath, 'apache_ant', '1.8.4')
   bzip2libpath = os.path.join(thirdpartypath, 'bzip2')
   buildpath = os.path.join(editorpath, 'tools', 'features',
                            'com.google.dart.tools.deploy.feature_releng')
-  utils = GetUtils(toolspath)
   buildos = utils.GuessOS()
 
   BUILD_OS = utils.GuessOS()
   DART_PATH = dartpath
   TOOLS_PATH = toolspath
 
   if (os.environ.get('DART_NO_UPLOAD') is not None):
     NO_UPLOAD = True
 
   # TODO(devoncarew): remove this hardcoded e:\ path
@@ skipping 852 matching lines @@
   """delete the given file - do not re-throw any exceptions that occur"""
   if os.path.exists(f):
     try:
       os.remove(f)
     except OSError:
       print 'error deleting %s' % f
 
 
 if __name__ == '__main__':
   sys.exit(main())