Export generator flavor to gyp scripts

pylib/gyp/__init__.py

 #!/usr/bin/env python
 
 # Copyright (c) 2012 Google Inc. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 import copy
 import gyp.input
 import optparse
 import os.path
@@ skipping 44 matching lines @@
   default_variables and includes will be copied before use.
   Returns the generator for the specified format and the
   data returned by loading the specified build files.
   """
   if params is None:
     params = {}
 
   flavor = None
   if '-' in format:
     format, params['flavor'] = format.split('-', 1)
+    flavor = params['flavor']

[justincohen, 2015/03/16 15:12:24]

is it necessary to pull this out into a new variable?  why not just:

default_variables['GENERATOR_FLAVOR'] = params['flavor'] or ""

[sdefresne, 2015/03/16 15:47:05]

The variable already existed (see above) but was never set (which took me some
time to find). And since a dictionary will raise an exception if accessing a
non-existent key, I preferred re-using the variable.

[sdefresne, 2015/03/16 15:49:00]

Done.

 
   default_variables = copy.copy(default_variables)
 
   # Default variables provided by this program and its modules should be
   # named WITH_CAPITAL_LETTERS to provide a distinct "best practice" namespace,
   # avoiding collisions with user and automatic variables.
   default_variables['GENERATOR'] = format
+  default_variables['GENERATOR_FLAVOR'] = flavor or ""
 
   # Format can be a custom python file, or by default the name of a module
   # within gyp.generator.
   if format.endswith('.py'):
     generator_name = os.path.splitext(format)[0]
     path, generator_name = os.path.split(generator_name)
 
     # Make sure the path to the custom generator is in sys.path
     # Don't worry about removing it once we are done.  Keeping the path
     # to each generator that is used in sys.path is likely harmless and
@@ skipping 445 matching lines @@
   except GypError, e:
     sys.stderr.write("gyp: %s\n" % e)
     return 1
 
 # NOTE: setuptools generated console_scripts calls function with no arguments
 def script_main():
   return main(sys.argv[1:])
 
 if __name__ == '__main__':
   sys.exit(script_main())