openmedialibrary_platform_w.../Lib/lib2to3/fixes/fix_zip.py

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2019-01-20 10:35:31 +00:00
"""
Fixer that changes zip(seq0, seq1, ...) into list(zip(seq0, seq1, ...)
unless there exists a 'from future_builtins import zip' statement in the
top-level namespace.
We avoid the transformation if the zip() call is directly contained in
iter(<>), list(<>), tuple(<>), sorted(<>), ...join(<>), or for V in <>:.
"""
# Local imports
from .. import fixer_base
from ..pytree import Node
from ..pygram import python_symbols as syms
from ..fixer_util import Name, ArgList, in_special_context
class FixZip(fixer_base.ConditionalFix):
BM_compatible = True
PATTERN = """
power< 'zip' args=trailer< '(' [any] ')' > [trailers=trailer*]
>
"""
skip_on = "future_builtins.zip"
def transform(self, node, results):
if self.should_skip(node):
return
if in_special_context(node):
return None
args = results['args'].clone()
args.prefix = ""
trailers = []
if 'trailers' in results:
trailers = [n.clone() for n in results['trailers']]
for n in trailers:
n.prefix = ""
new = Node(syms.power, [Name("zip"), args], prefix="")
new = Node(syms.power, [Name("list"), ArgList([new])] + trailers)
new.prefix = node.prefix
return new