Reland: Add --no-history option to fetch and gclient for shallow clones.

fetch.py

 #!/usr/bin/env python
 # Copyright (c) 2013 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.
 
 """
 Tool to perform checkouts in one easy command line!
 
 Usage:
   fetch <recipe> [--property=value [--property2=value2 ...]]
@@ skipping 96 matching lines @@
 
   def exists(self):
     return os.path.exists(os.path.join(os.getcwd(), self.root))
 
   def init(self):
     # Configure and do the gclient checkout.
     self.run_gclient('config', '--spec', self.spec['gclient_spec'])
     sync_cmd = ['sync']
     if self.options.nohooks:
       sync_cmd.append('--nohooks')
+    if self.options.no_history:
+      sync_cmd.append('--no-history')
     if self.spec.get('with_branch_heads', False):
       sync_cmd.append('--with_branch_heads')
     self.run_gclient(*sync_cmd)
 
     # Configure git.
     wd = os.path.join(self.base, self.root)
     if self.options.dry_run:
       print 'cd %s' % wd
     self.run_git(
         'submodule', 'foreach',
@@ skipping 73 matching lines @@
 usage: %s [options] <recipe> [--property=value [--property2=value2 ...]]
 
 This script can be used to download the Chromium sources. See
 http://www.chromium.org/developers/how-tos/get-the-code
 for full usage instructions.
 
 Valid options:
    -h, --help, help   Print this message.
    --nohooks          Don't run hooks after checkout.
    -n, --dry-run      Don't run commands, only print them.
+   --no-history       Perform shallow clones, don't fetch the full git history.
 """ % os.path.basename(sys.argv[0]))
   sys.exit(bool(msg))
 
 
 def handle_args(argv):
   """Gets the recipe name from the command line arguments."""
   if len(argv) <= 1:
     usage('Must specify a recipe.')
   if argv[1] in ('-h', '--help', 'help'):
     usage()
 
   dry_run = False
   nohooks = False
+  no_history = False
   while len(argv) >= 2:
     arg = argv[1]
     if not arg.startswith('-'):
       break
     argv.pop(1)
     if arg in ('-n', '--dry-run'):
       dry_run = True
     elif arg == '--nohooks':
       nohooks = True
+    elif arg == '--no-history':
+      no_history = True
     else:
       usage('Invalid option %s.' % arg)
 
   def looks_like_arg(arg):
     return arg.startswith('--') and arg.count('=') == 1
 
   bad_parms = [x for x in argv[2:] if not looks_like_arg(x)]
   if bad_parms:
     usage('Got bad arguments %s' % bad_parms)
 
   recipe = argv[1]
   props = argv[2:]
-  return optparse.Values({'dry_run':dry_run, 'nohooks':nohooks }), recipe, props
+  return (
+      optparse.Values(
+          {'dry_run':dry_run, 'nohooks':nohooks, 'no_history': no_history }),
+      recipe,
+      props)
 
 
 def run_recipe_fetch(recipe, props, aliased=False):
   """Invoke a recipe's fetch method with the passed-through args
   and return its json output as a python object."""
   recipe_path = os.path.abspath(os.path.join(SCRIPT_PATH, 'recipes', recipe))
   if not os.path.exists(recipe_path + '.py'):
     print "Could not find a recipe for %s" % recipe
     sys.exit(1)
 
@@ skipping 38 matching lines @@
 
 
 def main():
   options, recipe, props = handle_args(sys.argv)
   spec, root = run_recipe_fetch(recipe, props)
   return run(options, spec, root)
 
 
 if __name__ == '__main__':
   sys.exit(main())