lib-python.2.5.test.test_peepholer.py Maven / Gradle / Ivy
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Jython is an implementation of the high-level, dynamic, object-oriented
language Python written in 100% Pure Java, and seamlessly integrated with
the Java platform. It thus allows you to run Python on any Java platform.
import dis
import sys
from cStringIO import StringIO
import unittest
def disassemble(func):
f = StringIO()
tmp = sys.stdout
sys.stdout = f
dis.dis(func)
sys.stdout = tmp
result = f.getvalue()
f.close()
return result
def dis_single(line):
return disassemble(compile(line, '', 'single'))
class TestTranforms(unittest.TestCase):
def test_unot(self):
# UNARY_NOT JUMP_IF_FALSE POP_TOP --> JUMP_IF_TRUE POP_TOP'
def unot(x):
if not x == 2:
del x
asm = disassemble(unot)
for elem in ('UNARY_NOT', 'JUMP_IF_FALSE'):
self.assert_(elem not in asm)
for elem in ('JUMP_IF_TRUE', 'POP_TOP'):
self.assert_(elem in asm)
def test_elim_inversion_of_is_or_in(self):
for line, elem in (
('not a is b', '(is not)',),
('not a in b', '(not in)',),
('not a is not b', '(is)',),
('not a not in b', '(in)',),
):
asm = dis_single(line)
self.assert_(elem in asm)
def test_none_as_constant(self):
# LOAD_GLOBAL None --> LOAD_CONST None
def f(x):
None
return x
asm = disassemble(f)
for elem in ('LOAD_GLOBAL',):
self.assert_(elem not in asm)
for elem in ('LOAD_CONST', '(None)'):
self.assert_(elem in asm)
def f():
'Adding a docstring made this test fail in Py2.5.0'
return None
self.assert_('LOAD_CONST' in disassemble(f))
self.assert_('LOAD_GLOBAL' not in disassemble(f))
def test_while_one(self):
# Skip over: LOAD_CONST trueconst JUMP_IF_FALSE xx POP_TOP
def f():
while 1:
pass
return list
asm = disassemble(f)
for elem in ('LOAD_CONST', 'JUMP_IF_FALSE'):
self.assert_(elem not in asm)
for elem in ('JUMP_ABSOLUTE',):
self.assert_(elem in asm)
def test_pack_unpack(self):
for line, elem in (
('a, = a,', 'LOAD_CONST',),
('a, b = a, b', 'ROT_TWO',),
('a, b, c = a, b, c', 'ROT_THREE',),
):
asm = dis_single(line)
self.assert_(elem in asm)
self.assert_('BUILD_TUPLE' not in asm)
self.assert_('UNPACK_TUPLE' not in asm)
def test_folding_of_tuples_of_constants(self):
for line, elem in (
('a = 1,2,3', '((1, 2, 3))'),
('("a","b","c")', "(('a', 'b', 'c'))"),
('a,b,c = 1,2,3', '((1, 2, 3))'),
('(None, 1, None)', '((None, 1, None))'),
('((1, 2), 3, 4)', '(((1, 2), 3, 4))'),
):
asm = dis_single(line)
self.assert_(elem in asm)
self.assert_('BUILD_TUPLE' not in asm)
# Bug 1053819: Tuple of constants misidentified when presented with:
# . . . opcode_with_arg 100 unary_opcode BUILD_TUPLE 1 . . .
# The following would segfault upon compilation
def crater():
(~[
0, 1, 2, 3, 4, 5, 6, 7, 8, 9,
0, 1, 2, 3, 4, 5, 6, 7, 8, 9,
0, 1, 2, 3, 4, 5, 6, 7, 8, 9,
0, 1, 2, 3, 4, 5, 6, 7, 8, 9,
0, 1, 2, 3, 4, 5, 6, 7, 8, 9,
0, 1, 2, 3, 4, 5, 6, 7, 8, 9,
0, 1, 2, 3, 4, 5, 6, 7, 8, 9,
0, 1, 2, 3, 4, 5, 6, 7, 8, 9,
0, 1, 2, 3, 4, 5, 6, 7, 8, 9,
0, 1, 2, 3, 4, 5, 6, 7, 8, 9,
],)
def test_folding_of_binops_on_constants(self):
for line, elem in (
('a = 2+3+4', '(9)'), # chained fold
('"@"*4', "('@@@@')"), # check string ops
('a="abc" + "def"', "('abcdef')"), # check string ops
('a = 3**4', '(81)'), # binary power
('a = 3*4', '(12)'), # binary multiply
('a = 13//4', '(3)'), # binary floor divide
('a = 14%4', '(2)'), # binary modulo
('a = 2+3', '(5)'), # binary add
('a = 13-4', '(9)'), # binary subtract
('a = (12,13)[1]', '(13)'), # binary subscr
('a = 13 << 2', '(52)'), # binary lshift
('a = 13 >> 2', '(3)'), # binary rshift
('a = 13 & 7', '(5)'), # binary and
('a = 13 ^ 7', '(10)'), # binary xor
('a = 13 | 7', '(15)'), # binary or
):
asm = dis_single(line)
self.assert_(elem in asm, asm)
self.assert_('BINARY_' not in asm)
# Verify that unfoldables are skipped
asm = dis_single('a=2+"b"')
self.assert_('(2)' in asm)
self.assert_("('b')" in asm)
# Verify that large sequences do not result from folding
asm = dis_single('a="x"*1000')
self.assert_('(1000)' in asm)
def test_folding_of_unaryops_on_constants(self):
for line, elem in (
('`1`', "('1')"), # unary convert
('-0.5', '(-0.5)'), # unary negative
('~-2', '(1)'), # unary invert
):
asm = dis_single(line)
self.assert_(elem in asm, asm)
self.assert_('UNARY_' not in asm)
# Verify that unfoldables are skipped
for line, elem in (
('-"abc"', "('abc')"), # unary negative
('~"abc"', "('abc')"), # unary invert
):
asm = dis_single(line)
self.assert_(elem in asm, asm)
self.assert_('UNARY_' in asm)
def test_elim_extra_return(self):
# RETURN LOAD_CONST None RETURN --> RETURN
def f(x):
return x
asm = disassemble(f)
self.assert_('LOAD_CONST' not in asm)
self.assert_('(None)' not in asm)
self.assertEqual(asm.split().count('RETURN_VALUE'), 1)
def test_main(verbose=None):
import sys
from test import test_support
test_classes = (TestTranforms,)
test_support.run_unittest(*test_classes)
# verify reference counting
if verbose and hasattr(sys, "gettotalrefcount"):
import gc
counts = [None] * 5
for i in xrange(len(counts)):
test_support.run_unittest(*test_classes)
gc.collect()
counts[i] = sys.gettotalrefcount()
print counts
if __name__ == "__main__":
test_main(verbose=True)