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diff --git a/lib/python2.7/lib2to3/fixes/fix_map.py b/lib/python2.7/lib2to3/fixes/fix_map.py
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+# Copyright 2007 Google, Inc. All Rights Reserved.
+# Licensed to PSF under a Contributor Agreement.
+
+"""Fixer that changes map(F, ...) into list(map(F, ...)) unless there
+exists a 'from future_builtins import map' statement in the top-level
+namespace.
+
+As a special case, map(None, X) is changed into list(X). (This is
+necessary because the semantics are changed in this case -- the new
+map(None, X) is equivalent to [(x,) for x in X].)
+
+We avoid the transformation (except for the special case mentioned
+above) if the map() call is directly contained in iter(<>), list(<>),
+tuple(<>), sorted(<>), ...join(<>), or for V in <>:.
+
+NOTE: This is still not correct if the original code was depending on
+map(F, X, Y, ...) to go on until the longest argument is exhausted,
+substituting None for missing values -- like zip(), it now stops as
+soon as the shortest argument is exhausted.
+"""
+
+# Local imports
+from ..pgen2 import token
+from .. import fixer_base
+from ..fixer_util import Name, Call, ListComp, in_special_context
+from ..pygram import python_symbols as syms
+
+class FixMap(fixer_base.ConditionalFix):
+ BM_compatible = True
+
+ PATTERN = """
+ map_none=power<
+ 'map'
+ trailer< '(' arglist< 'None' ',' arg=any [','] > ')' >
+ >
+ |
+ map_lambda=power<
+ 'map'
+ trailer<
+ '('
+ arglist<
+ lambdef< 'lambda'
+ (fp=NAME | vfpdef< '(' fp=NAME ')'> ) ':' xp=any
+ >
+ ','
+ it=any
+ >
+ ')'
+ >
+ >
+ |
+ power<
+ 'map' trailer< '(' [arglist=any] ')' >
+ >
+ """
+
+ skip_on = 'future_builtins.map'
+
+ def transform(self, node, results):
+ if self.should_skip(node):
+ return
+
+ if node.parent.type == syms.simple_stmt:
+ self.warning(node, "You should use a for loop here")
+ new = node.clone()
+ new.prefix = u""
+ new = Call(Name(u"list"), [new])
+ elif "map_lambda" in results:
+ new = ListComp(results["xp"].clone(),
+ results["fp"].clone(),
+ results["it"].clone())
+ else:
+ if "map_none" in results:
+ new = results["arg"].clone()
+ else:
+ if "arglist" in results:
+ args = results["arglist"]
+ if args.type == syms.arglist and \
+ args.children[0].type == token.NAME and \
+ args.children[0].value == "None":
+ self.warning(node, "cannot convert map(None, ...) "
+ "with multiple arguments because map() "
+ "now truncates to the shortest sequence")
+ return
+ if in_special_context(node):
+ return None
+ new = node.clone()
+ new.prefix = u""
+ new = Call(Name(u"list"), [new])
+ new.prefix = node.prefix
+ return new