Python code coverage for Lib/test/test_peepholer.py

#	count	content
1	n/a	import dis
2	n/a	import unittest
3	n/a
4	n/a	from test.bytecode_helper import BytecodeTestCase
5	n/a
6	n/a	class TestTranforms(BytecodeTestCase):
7	n/a
8	n/a	def test_unot(self):
9	n/a	# UNARY_NOT POP_JUMP_IF_FALSE --> POP_JUMP_IF_TRUE'
10	n/a	def unot(x):
11	n/a	if not x == 2:
12	n/a	del x
13	n/a	self.assertNotInBytecode(unot, 'UNARY_NOT')
14	n/a	self.assertNotInBytecode(unot, 'POP_JUMP_IF_FALSE')
15	n/a	self.assertInBytecode(unot, 'POP_JUMP_IF_TRUE')
16	n/a
17	n/a	def test_elim_inversion_of_is_or_in(self):
18	n/a	for line, cmp_op in (
19	n/a	('not a is b', 'is not',),
20	n/a	('not a in b', 'not in',),
21	n/a	('not a is not b', 'is',),
22	n/a	('not a not in b', 'in',),
23	n/a	):
24	n/a	code = compile(line, '', 'single')
25	n/a	self.assertInBytecode(code, 'COMPARE_OP', cmp_op)
26	n/a
27	n/a	def test_global_as_constant(self):
28	n/a	# LOAD_GLOBAL None/True/False --> LOAD_CONST None/True/False
29	n/a	def f():
30	n/a	x = None
31	n/a	x = None
32	n/a	return x
33	n/a	def g():
34	n/a	x = True
35	n/a	return x
36	n/a	def h():
37	n/a	x = False
38	n/a	return x
39	n/a
40	n/a	for func, elem in ((f, None), (g, True), (h, False)):
41	n/a	self.assertNotInBytecode(func, 'LOAD_GLOBAL')
42	n/a	self.assertInBytecode(func, 'LOAD_CONST', elem)
43	n/a
44	n/a	def f():
45	n/a	'Adding a docstring made this test fail in Py2.5.0'
46	n/a	return None
47	n/a
48	n/a	self.assertNotInBytecode(f, 'LOAD_GLOBAL')
49	n/a	self.assertInBytecode(f, 'LOAD_CONST', None)
50	n/a
51	n/a	def test_while_one(self):
52	n/a	# Skip over: LOAD_CONST trueconst POP_JUMP_IF_FALSE xx
53	n/a	def f():
54	n/a	while 1:
55	n/a	pass
56	n/a	return list
57	n/a	for elem in ('LOAD_CONST', 'POP_JUMP_IF_FALSE'):
58	n/a	self.assertNotInBytecode(f, elem)
59	n/a	for elem in ('JUMP_ABSOLUTE',):
60	n/a	self.assertInBytecode(f, elem)
61	n/a
62	n/a	def test_pack_unpack(self):
63	n/a	for line, elem in (
64	n/a	('a, = a,', 'LOAD_CONST',),
65	n/a	('a, b = a, b', 'ROT_TWO',),
66	n/a	('a, b, c = a, b, c', 'ROT_THREE',),
67	n/a	):
68	n/a	code = compile(line,'','single')
69	n/a	self.assertInBytecode(code, elem)
70	n/a	self.assertNotInBytecode(code, 'BUILD_TUPLE')
71	n/a	self.assertNotInBytecode(code, 'UNPACK_TUPLE')
72	n/a
73	n/a	def test_folding_of_tuples_of_constants(self):
74	n/a	for line, elem in (
75	n/a	('a = 1,2,3', (1, 2, 3)),
76	n/a	('("a","b","c")', ('a', 'b', 'c')),
77	n/a	('a,b,c = 1,2,3', (1, 2, 3)),
78	n/a	('(None, 1, None)', (None, 1, None)),
79	n/a	('((1, 2), 3, 4)', ((1, 2), 3, 4)),
80	n/a	):
81	n/a	code = compile(line,'','single')
82	n/a	self.assertInBytecode(code, 'LOAD_CONST', elem)
83	n/a	self.assertNotInBytecode(code, 'BUILD_TUPLE')
84	n/a
85	n/a	# Long tuples should be folded too.
86	n/a	code = compile(repr(tuple(range(10000))),'','single')
87	n/a	self.assertNotInBytecode(code, 'BUILD_TUPLE')
88	n/a	# One LOAD_CONST for the tuple, one for the None return value
89	n/a	load_consts = [instr for instr in dis.get_instructions(code)
90	n/a	if instr.opname == 'LOAD_CONST']
91	n/a	self.assertEqual(len(load_consts), 2)
92	n/a
93	n/a	# Bug 1053819: Tuple of constants misidentified when presented with:
94	n/a	# . . . opcode_with_arg 100 unary_opcode BUILD_TUPLE 1 . . .
95	n/a	# The following would segfault upon compilation
96	n/a	def crater():
97	n/a	(~[
98	n/a	0, 1, 2, 3, 4, 5, 6, 7, 8, 9,
99	n/a	0, 1, 2, 3, 4, 5, 6, 7, 8, 9,
100	n/a	0, 1, 2, 3, 4, 5, 6, 7, 8, 9,
101	n/a	0, 1, 2, 3, 4, 5, 6, 7, 8, 9,
102	n/a	0, 1, 2, 3, 4, 5, 6, 7, 8, 9,
103	n/a	0, 1, 2, 3, 4, 5, 6, 7, 8, 9,
104	n/a	0, 1, 2, 3, 4, 5, 6, 7, 8, 9,
105	n/a	0, 1, 2, 3, 4, 5, 6, 7, 8, 9,
106	n/a	0, 1, 2, 3, 4, 5, 6, 7, 8, 9,
107	n/a	0, 1, 2, 3, 4, 5, 6, 7, 8, 9,
108	n/a	],)
109	n/a
110	n/a	def test_folding_of_lists_of_constants(self):
111	n/a	for line, elem in (
112	n/a	# in/not in constants with BUILD_LIST should be folded to a tuple:
113	n/a	('a in [1,2,3]', (1, 2, 3)),
114	n/a	('a not in ["a","b","c"]', ('a', 'b', 'c')),
115	n/a	('a in [None, 1, None]', (None, 1, None)),
116	n/a	('a not in [(1, 2), 3, 4]', ((1, 2), 3, 4)),
117	n/a	):
118	n/a	code = compile(line, '', 'single')
119	n/a	self.assertInBytecode(code, 'LOAD_CONST', elem)
120	n/a	self.assertNotInBytecode(code, 'BUILD_LIST')
121	n/a
122	n/a	def test_folding_of_sets_of_constants(self):
123	n/a	for line, elem in (
124	n/a	# in/not in constants with BUILD_SET should be folded to a frozenset:
125	n/a	('a in {1,2,3}', frozenset({1, 2, 3})),
126	n/a	('a not in {"a","b","c"}', frozenset({'a', 'c', 'b'})),
127	n/a	('a in {None, 1, None}', frozenset({1, None})),
128	n/a	('a not in {(1, 2), 3, 4}', frozenset({(1, 2), 3, 4})),
129	n/a	('a in {1, 2, 3, 3, 2, 1}', frozenset({1, 2, 3})),
130	n/a	):
131	n/a	code = compile(line, '', 'single')
132	n/a	self.assertNotInBytecode(code, 'BUILD_SET')
133	n/a	self.assertInBytecode(code, 'LOAD_CONST', elem)
134	n/a
135	n/a	# Ensure that the resulting code actually works:
136	n/a	def f(a):
137	n/a	return a in {1, 2, 3}
138	n/a
139	n/a	def g(a):
140	n/a	return a not in {1, 2, 3}
141	n/a
142	n/a	self.assertTrue(f(3))
143	n/a	self.assertTrue(not f(4))
144	n/a
145	n/a	self.assertTrue(not g(3))
146	n/a	self.assertTrue(g(4))
147	n/a
148	n/a
149	n/a	def test_folding_of_binops_on_constants(self):
150	n/a	for line, elem in (
151	n/a	('a = 2+3+4', 9), # chained fold
152	n/a	('"@"*4', '@@@@'), # check string ops
153	n/a	('a="abc" + "def"', 'abcdef'), # check string ops
154	n/a	('a = 3**4', 81), # binary power
155	n/a	('a = 3*4', 12), # binary multiply
156	n/a	('a = 13//4', 3), # binary floor divide
157	n/a	('a = 14%4', 2), # binary modulo
158	n/a	('a = 2+3', 5), # binary add
159	n/a	('a = 13-4', 9), # binary subtract
160	n/a	('a = (12,13)[1]', 13), # binary subscr
161	n/a	('a = 13 << 2', 52), # binary lshift
162	n/a	('a = 13 >> 2', 3), # binary rshift
163	n/a	('a = 13 & 7', 5), # binary and
164	n/a	('a = 13 ^ 7', 10), # binary xor
165	n/a	('a = 13 \| 7', 15), # binary or
166	n/a	):
167	n/a	code = compile(line, '', 'single')
168	n/a	self.assertInBytecode(code, 'LOAD_CONST', elem)
169	n/a	for instr in dis.get_instructions(code):
170	n/a	self.assertFalse(instr.opname.startswith('BINARY_'))
171	n/a
172	n/a	# Verify that unfoldables are skipped
173	n/a	code = compile('a=2+"b"', '', 'single')
174	n/a	self.assertInBytecode(code, 'LOAD_CONST', 2)
175	n/a	self.assertInBytecode(code, 'LOAD_CONST', 'b')
176	n/a
177	n/a	# Verify that large sequences do not result from folding
178	n/a	code = compile('a="x"*1000', '', 'single')
179	n/a	self.assertInBytecode(code, 'LOAD_CONST', 1000)
180	n/a
181	n/a	def test_binary_subscr_on_unicode(self):
182	n/a	# valid code get optimized
183	n/a	code = compile('"foo"[0]', '', 'single')
184	n/a	self.assertInBytecode(code, 'LOAD_CONST', 'f')
185	n/a	self.assertNotInBytecode(code, 'BINARY_SUBSCR')
186	n/a	code = compile('"\u0061\uffff"[1]', '', 'single')
187	n/a	self.assertInBytecode(code, 'LOAD_CONST', '\uffff')
188	n/a	self.assertNotInBytecode(code,'BINARY_SUBSCR')
189	n/a
190	n/a	# With PEP 393, non-BMP char get optimized
191	n/a	code = compile('"\U00012345"[0]', '', 'single')
192	n/a	self.assertInBytecode(code, 'LOAD_CONST', '\U00012345')
193	n/a	self.assertNotInBytecode(code, 'BINARY_SUBSCR')
194	n/a
195	n/a	# invalid code doesn't get optimized
196	n/a	# out of range
197	n/a	code = compile('"fuu"[10]', '', 'single')
198	n/a	self.assertInBytecode(code, 'BINARY_SUBSCR')
199	n/a
200	n/a	def test_folding_of_unaryops_on_constants(self):
201	n/a	for line, elem in (
202	n/a	('-0.5', -0.5), # unary negative
203	n/a	('-0.0', -0.0), # -0.0
204	n/a	('-(1.0-1.0)', -0.0), # -0.0 after folding
205	n/a	('-0', 0), # -0
206	n/a	('~-2', 1), # unary invert
207	n/a	('+1', 1), # unary positive
208	n/a	):
209	n/a	code = compile(line, '', 'single')
210	n/a	self.assertInBytecode(code, 'LOAD_CONST', elem)
211	n/a	for instr in dis.get_instructions(code):
212	n/a	self.assertFalse(instr.opname.startswith('UNARY_'))
213	n/a
214	n/a	# Check that -0.0 works after marshaling
215	n/a	def negzero():
216	n/a	return -(1.0-1.0)
217	n/a
218	n/a	for instr in dis.get_instructions(code):
219	n/a	self.assertFalse(instr.opname.startswith('UNARY_'))
220	n/a
221	n/a	# Verify that unfoldables are skipped
222	n/a	for line, elem, opname in (
223	n/a	('-"abc"', 'abc', 'UNARY_NEGATIVE'),
224	n/a	('~"abc"', 'abc', 'UNARY_INVERT'),
225	n/a	):
226	n/a	code = compile(line, '', 'single')
227	n/a	self.assertInBytecode(code, 'LOAD_CONST', elem)
228	n/a	self.assertInBytecode(code, opname)
229	n/a
230	n/a	def test_elim_extra_return(self):
231	n/a	# RETURN LOAD_CONST None RETURN --> RETURN
232	n/a	def f(x):
233	n/a	return x
234	n/a	self.assertNotInBytecode(f, 'LOAD_CONST', None)
235	n/a	returns = [instr for instr in dis.get_instructions(f)
236	n/a	if instr.opname == 'RETURN_VALUE']
237	n/a	self.assertEqual(len(returns), 1)
238	n/a
239	n/a	def test_elim_jump_to_return(self):
240	n/a	# JUMP_FORWARD to RETURN --> RETURN
241	n/a	def f(cond, true_value, false_value):
242	n/a	return true_value if cond else false_value
243	n/a	self.assertNotInBytecode(f, 'JUMP_FORWARD')
244	n/a	self.assertNotInBytecode(f, 'JUMP_ABSOLUTE')
245	n/a	returns = [instr for instr in dis.get_instructions(f)
246	n/a	if instr.opname == 'RETURN_VALUE']
247	n/a	self.assertEqual(len(returns), 2)
248	n/a
249	n/a	def test_elim_jump_after_return1(self):
250	n/a	# Eliminate dead code: jumps immediately after returns can't be reached
251	n/a	def f(cond1, cond2):
252	n/a	if cond1: return 1
253	n/a	if cond2: return 2
254	n/a	while 1:
255	n/a	return 3
256	n/a	while 1:
257	n/a	if cond1: return 4
258	n/a	return 5
259	n/a	return 6
260	n/a	self.assertNotInBytecode(f, 'JUMP_FORWARD')
261	n/a	self.assertNotInBytecode(f, 'JUMP_ABSOLUTE')
262	n/a	returns = [instr for instr in dis.get_instructions(f)
263	n/a	if instr.opname == 'RETURN_VALUE']
264	n/a	self.assertEqual(len(returns), 6)
265	n/a
266	n/a	def test_elim_jump_after_return2(self):
267	n/a	# Eliminate dead code: jumps immediately after returns can't be reached
268	n/a	def f(cond1, cond2):
269	n/a	while 1:
270	n/a	if cond1: return 4
271	n/a	self.assertNotInBytecode(f, 'JUMP_FORWARD')
272	n/a	# There should be one jump for the while loop.
273	n/a	returns = [instr for instr in dis.get_instructions(f)
274	n/a	if instr.opname == 'JUMP_ABSOLUTE']
275	n/a	self.assertEqual(len(returns), 1)
276	n/a	returns = [instr for instr in dis.get_instructions(f)
277	n/a	if instr.opname == 'RETURN_VALUE']
278	n/a	self.assertEqual(len(returns), 2)
279	n/a
280	n/a	def test_make_function_doesnt_bail(self):
281	n/a	def f():
282	n/a	def g()->1+1:
283	n/a	pass
284	n/a	return g
285	n/a	self.assertNotInBytecode(f, 'BINARY_ADD')
286	n/a
287	n/a	def test_constant_folding(self):
288	n/a	# Issue #11244: aggressive constant folding.
289	n/a	exprs = [
290	n/a	'3 * -5',
291	n/a	'-3 * 5',
292	n/a	'2 * (3 * 4)',
293	n/a	'(2 * 3) * 4',
294	n/a	'(-1, 2, 3)',
295	n/a	'(1, -2, 3)',
296	n/a	'(1, 2, -3)',
297	n/a	'(1, 2, -3) * 6',
298	n/a	'lambda x: x in {(3 * -5) + (-1 - 6), (1, -2, 3) * 2, None}',
299	n/a	]
300	n/a	for e in exprs:
301	n/a	code = compile(e, '', 'single')
302	n/a	for instr in dis.get_instructions(code):
303	n/a	self.assertFalse(instr.opname.startswith('UNARY_'))
304	n/a	self.assertFalse(instr.opname.startswith('BINARY_'))
305	n/a	self.assertFalse(instr.opname.startswith('BUILD_'))
306	n/a
307	n/a
308	n/a	class TestBuglets(unittest.TestCase):
309	n/a
310	n/a	def test_bug_11510(self):
311	n/a	# folded constant set optimization was commingled with the tuple
312	n/a	# unpacking optimization which would fail if the set had duplicate
313	n/a	# elements so that the set length was unexpected
314	n/a	def f():
315	n/a	x, y = {1, 1}
316	n/a	return x, y
317	n/a	with self.assertRaises(ValueError):
318	n/a	f()
319	n/a
320	n/a
321	n/a	if __name__ == "__main__":
322	n/a	unittest.main()