AppPkg/Applications/Python/Python-2.7.2/Lib/lib2to3/fixes/fix_isinstance.py

   1 # Copyright 2008 Armin Ronacher.
   2 # Licensed to PSF under a Contributor Agreement.
   3
   4 """Fixer that cleans up a tuple argument to isinstance after the tokens
   5 in it were fixed.  This is mainly used to remove double occurrences of
   6 tokens as a leftover of the long -> int / unicode -> str conversion.
   7
   8 eg.  isinstance(x, (int, long)) -> isinstance(x, (int, int))
   9        -> isinstance(x, int)
  10 """
  11
  12 from .. import fixer_base
  13 from ..fixer_util import token
  14
  15
  16 class FixIsinstance(fixer_base.BaseFix):
  17     BM_compatible = True
  18     PATTERN = """
  19     power<
  20         'isinstance'
  21         trailer< '(' arglist< any ',' atom< '('
  22             args=testlist_gexp< any+ >
  23         ')' > > ')' >
  24     >
  25     """
  26
  27     run_order = 6
  28
  29     def transform(self, node, results):
  30         names_inserted = set()
  31         testlist = results["args"]
  32         args = testlist.children
  33         new_args = []
  34         iterator = enumerate(args)
  35         for idx, arg in iterator:
  36             if arg.type == token.NAME and arg.value in names_inserted:
  37                 if idx < len(args) - 1 and args[idx + 1].type == token.COMMA:
  38                     iterator.next()
  39                     continue
  40             else:
  41                 new_args.append(arg)
  42                 if arg.type == token.NAME:
  43                     names_inserted.add(arg.value)
  44         if new_args and new_args[-1].type == token.COMMA:
  45             del new_args[-1]
  46         if len(new_args) == 1:
  47             atom = testlist.parent
  48             new_args[0].prefix = atom.prefix
  49             atom.replace(new_args[0])
  50         else:
  51             args[:] = new_args
  52             node.changed()