Python code coverage for Lib/lib2to3/fixes/fix_map.py

#	count	content
1	n/a	# Copyright 2007 Google, Inc. All Rights Reserved.
2	n/a	# Licensed to PSF under a Contributor Agreement.
3	n/a
4	n/a	"""Fixer that changes map(F, ...) into list(map(F, ...)) unless there
5	n/a	exists a 'from future_builtins import map' statement in the top-level
6	n/a	namespace.
7	n/a
8	n/a	As a special case, map(None, X) is changed into list(X). (This is
9	n/a	necessary because the semantics are changed in this case -- the new
10	n/a	map(None, X) is equivalent to [(x,) for x in X].)
11	n/a
12	n/a	We avoid the transformation (except for the special case mentioned
13	n/a	above) if the map() call is directly contained in iter(<>), list(<>),
14	n/a	tuple(<>), sorted(<>), ...join(<>), or for V in <>:.
15	n/a
16	n/a	NOTE: This is still not correct if the original code was depending on
17	n/a	map(F, X, Y, ...) to go on until the longest argument is exhausted,
18	n/a	substituting None for missing values -- like zip(), it now stops as
19	n/a	soon as the shortest argument is exhausted.
20	n/a	"""
21	n/a
22	n/a	# Local imports
23	n/a	from ..pgen2 import token
24	n/a	from .. import fixer_base
25	n/a	from ..fixer_util import Name, Call, ListComp, in_special_context
26	n/a	from ..pygram import python_symbols as syms
27	n/a
28	n/a	class FixMap(fixer_base.ConditionalFix):
29	n/a	BM_compatible = True
30	n/a
31	n/a	PATTERN = """
32	n/a	map_none=power<
33	n/a	'map'
34	n/a	trailer< '(' arglist< 'None' ',' arg=any [','] > ')' >
35	n/a	>
36	n/a	\|
37	n/a	map_lambda=power<
38	n/a	'map'
39	n/a	trailer<
40	n/a	'('
41	n/a	arglist<
42	n/a	lambdef< 'lambda'
43	n/a	(fp=NAME \| vfpdef< '(' fp=NAME ')'> ) ':' xp=any
44	n/a	>
45	n/a	','
46	n/a	it=any
47	n/a	>
48	n/a	')'
49	n/a	>
50	n/a	>
51	n/a	\|
52	n/a	power<
53	n/a	'map' trailer< '(' [arglist=any] ')' >
54	n/a	>
55	n/a	"""
56	n/a
57	n/a	skip_on = 'future_builtins.map'
58	n/a
59	n/a	def transform(self, node, results):
60	n/a	if self.should_skip(node):
61	n/a	return
62	n/a
63	n/a	if node.parent.type == syms.simple_stmt:
64	n/a	self.warning(node, "You should use a for loop here")
65	n/a	new = node.clone()
66	n/a	new.prefix = ""
67	n/a	new = Call(Name("list"), [new])
68	n/a	elif "map_lambda" in results:
69	n/a	new = ListComp(results["xp"].clone(),
70	n/a	results["fp"].clone(),
71	n/a	results["it"].clone())
72	n/a	else:
73	n/a	if "map_none" in results:
74	n/a	new = results["arg"].clone()
75	n/a	else:
76	n/a	if "arglist" in results:
77	n/a	args = results["arglist"]
78	n/a	if args.type == syms.arglist and \
79	n/a	args.children[0].type == token.NAME and \
80	n/a	args.children[0].value == "None":
81	n/a	self.warning(node, "cannot convert map(None, ...) "
82	n/a	"with multiple arguments because map() "
83	n/a	"now truncates to the shortest sequence")
84	n/a	return
85	n/a	if in_special_context(node):
86	n/a	return None
87	n/a	new = node.clone()
88	n/a	new.prefix = ""
89	n/a	new = Call(Name("list"), [new])
90	n/a	new.prefix = node.prefix
91	n/a	return new