# Copyright 2008 Armin Ronacher.
# Licensed to PSF under a Contributor Agreement.

"""Fixer that cleans up a tuple argument to isinstance after the tokens
in it were fixed. This is mainly used to remove double occurrences of
tokens as a leftover of the long -> int / unicode -> str conversion.

eg. isinstance(x, (int, long)) -> isinstance(x, (int, int))
-> isinstance(x, int)
"""

from .. import fixer_base
from ..fixer_util import token


class FixIsinstance(fixer_base.BaseFix):
BM_compatible = True
PATTERN = """
power<
'isinstance'
trailer< '(' arglist< any ',' atom< '('
args=testlist_gexp< any+ >
')' > > ')' >
>
"""

run_order = 6

def transform(self, node, results):
names_inserted = set()
testlist = results["args"]
args = testlist.children
new_args = []
iterator = enumerate(args)
for idx, arg in iterator:
if arg.type == token.NAME and arg.value in names_inserted:
if idx < len(args) - 1 and args[idx + 1].type == token.COMMA:
iterator.next()
continue
else:
new_args.append(arg)
if arg.type == token.NAME:
names_inserted.add(arg.value)
if new_args and new_args[-1].type == token.COMMA:
del new_args[-1]
if len(new_args) == 1:
atom = testlist.parent
new_args[0].prefix = atom.prefix
atom.replace(new_args[0])
else:
args[:] = new_args
node.changed()