mirror of
https://github.com/python/cpython.git
synced 2025-11-04 03:44:55 +00:00
2c31a058eb
Example:
>>> import dis
>>> dis.dis(compile('1,2,3', '', 'eval'))
0 0 LOAD_CONST 3 ((1, 2, 3))
3 RETURN_VALUE
114 lines
3.3 KiB
Python
114 lines
3.3 KiB
Python
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 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))',),
|
|
):
|
|
asm = dis_single(line)
|
|
self.assert_(elem in asm)
|
|
self.assert_('BUILD_TUPLE' not 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)
|