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

#	count	content
1	n/a	"""Fixer for 'raise E, V, T'
2	n/a
3	n/a	raise -> raise
4	n/a	raise E -> raise E
5	n/a	raise E, V -> raise E(V)
6	n/a	raise E, V, T -> raise E(V).with_traceback(T)
7	n/a	raise E, None, T -> raise E.with_traceback(T)
8	n/a
9	n/a	raise (((E, E'), E''), E'''), V -> raise E(V)
10	n/a	raise "foo", V, T -> warns about string exceptions
11	n/a
12	n/a
13	n/a	CAVEATS:
14	n/a	1) "raise E, V" will be incorrectly translated if V is an exception
15	n/a	instance. The correct Python 3 idiom is
16	n/a
17	n/a	raise E from V
18	n/a
19	n/a	but since we can't detect instance-hood by syntax alone and since
20	n/a	any client code would have to be changed as well, we don't automate
21	n/a	this.
22	n/a	"""
23	n/a	# Author: Collin Winter
24	n/a
25	n/a	# Local imports
26	n/a	from .. import pytree
27	n/a	from ..pgen2 import token
28	n/a	from .. import fixer_base
29	n/a	from ..fixer_util import Name, Call, Attr, ArgList, is_tuple
30	n/a
31	n/a	class FixRaise(fixer_base.BaseFix):
32	n/a
33	n/a	BM_compatible = True
34	n/a	PATTERN = """
35	n/a	raise_stmt< 'raise' exc=any [',' val=any [',' tb=any]] >
36	n/a	"""
37	n/a
38	n/a	def transform(self, node, results):
39	n/a	syms = self.syms
40	n/a
41	n/a	exc = results["exc"].clone()
42	n/a	if exc.type == token.STRING:
43	n/a	msg = "Python 3 does not support string exceptions"
44	n/a	self.cannot_convert(node, msg)
45	n/a	return
46	n/a
47	n/a	# Python 2 supports
48	n/a	# raise ((((E1, E2), E3), E4), E5), V
49	n/a	# as a synonym for
50	n/a	# raise E1, V
51	n/a	# Since Python 3 will not support this, we recurse down any tuple
52	n/a	# literals, always taking the first element.
53	n/a	if is_tuple(exc):
54	n/a	while is_tuple(exc):
55	n/a	# exc.children[1:-1] is the unparenthesized tuple
56	n/a	# exc.children[1].children[0] is the first element of the tuple
57	n/a	exc = exc.children[1].children[0].clone()
58	n/a	exc.prefix = " "
59	n/a
60	n/a	if "val" not in results:
61	n/a	# One-argument raise
62	n/a	new = pytree.Node(syms.raise_stmt, [Name("raise"), exc])
63	n/a	new.prefix = node.prefix
64	n/a	return new
65	n/a
66	n/a	val = results["val"].clone()
67	n/a	if is_tuple(val):
68	n/a	args = [c.clone() for c in val.children[1:-1]]
69	n/a	else:
70	n/a	val.prefix = ""
71	n/a	args = [val]
72	n/a
73	n/a	if "tb" in results:
74	n/a	tb = results["tb"].clone()
75	n/a	tb.prefix = ""
76	n/a
77	n/a	e = exc
78	n/a	# If there's a traceback and None is passed as the value, then don't
79	n/a	# add a call, since the user probably just wants to add a
80	n/a	# traceback. See issue #9661.
81	n/a	if val.type != token.NAME or val.value != "None":
82	n/a	e = Call(exc, args)
83	n/a	with_tb = Attr(e, Name('with_traceback')) + [ArgList([tb])]
84	n/a	new = pytree.Node(syms.simple_stmt, [Name("raise")] + with_tb)
85	n/a	new.prefix = node.prefix
86	n/a	return new
87	n/a	else:
88	n/a	return pytree.Node(syms.raise_stmt,
89	n/a	[Name("raise"), Call(exc, args)],
90	n/a	prefix=node.prefix)