mirror of
https://github.com/python/cpython.git
synced 2025-07-16 15:55:18 +00:00

Previously, CO_NOFREE was set in the compiler, which meant it could end up being set incorrectly when code objects were created directly. Setting it in the constructor based on freevars and cellvars ensures it is always accurate, regardless of how the code object is defined.
367 lines
10 KiB
Python
367 lines
10 KiB
Python
"""This module includes tests of the code object representation.
|
|
|
|
>>> def f(x):
|
|
... def g(y):
|
|
... return x + y
|
|
... return g
|
|
...
|
|
|
|
>>> dump(f.__code__)
|
|
name: f
|
|
argcount: 1
|
|
kwonlyargcount: 0
|
|
names: ()
|
|
varnames: ('x', 'g')
|
|
cellvars: ('x',)
|
|
freevars: ()
|
|
nlocals: 2
|
|
flags: 3
|
|
consts: ('None', '<code object g>', "'f.<locals>.g'")
|
|
|
|
>>> dump(f(4).__code__)
|
|
name: g
|
|
argcount: 1
|
|
kwonlyargcount: 0
|
|
names: ()
|
|
varnames: ('y',)
|
|
cellvars: ()
|
|
freevars: ('x',)
|
|
nlocals: 1
|
|
flags: 19
|
|
consts: ('None',)
|
|
|
|
>>> def h(x, y):
|
|
... a = x + y
|
|
... b = x - y
|
|
... c = a * b
|
|
... return c
|
|
...
|
|
|
|
>>> dump(h.__code__)
|
|
name: h
|
|
argcount: 2
|
|
kwonlyargcount: 0
|
|
names: ()
|
|
varnames: ('x', 'y', 'a', 'b', 'c')
|
|
cellvars: ()
|
|
freevars: ()
|
|
nlocals: 5
|
|
flags: 67
|
|
consts: ('None',)
|
|
|
|
>>> def attrs(obj):
|
|
... print(obj.attr1)
|
|
... print(obj.attr2)
|
|
... print(obj.attr3)
|
|
|
|
>>> dump(attrs.__code__)
|
|
name: attrs
|
|
argcount: 1
|
|
kwonlyargcount: 0
|
|
names: ('print', 'attr1', 'attr2', 'attr3')
|
|
varnames: ('obj',)
|
|
cellvars: ()
|
|
freevars: ()
|
|
nlocals: 1
|
|
flags: 67
|
|
consts: ('None',)
|
|
|
|
>>> def optimize_away():
|
|
... 'doc string'
|
|
... 'not a docstring'
|
|
... 53
|
|
... 0x53
|
|
|
|
>>> dump(optimize_away.__code__)
|
|
name: optimize_away
|
|
argcount: 0
|
|
kwonlyargcount: 0
|
|
names: ()
|
|
varnames: ()
|
|
cellvars: ()
|
|
freevars: ()
|
|
nlocals: 0
|
|
flags: 67
|
|
consts: ("'doc string'", 'None')
|
|
|
|
>>> def keywordonly_args(a,b,*,k1):
|
|
... return a,b,k1
|
|
...
|
|
|
|
>>> dump(keywordonly_args.__code__)
|
|
name: keywordonly_args
|
|
argcount: 2
|
|
kwonlyargcount: 1
|
|
names: ()
|
|
varnames: ('a', 'b', 'k1')
|
|
cellvars: ()
|
|
freevars: ()
|
|
nlocals: 3
|
|
flags: 67
|
|
consts: ('None',)
|
|
|
|
"""
|
|
|
|
import inspect
|
|
import sys
|
|
import threading
|
|
import unittest
|
|
import weakref
|
|
try:
|
|
import ctypes
|
|
except ImportError:
|
|
ctypes = None
|
|
from test.support import (run_doctest, run_unittest, cpython_only,
|
|
check_impl_detail)
|
|
|
|
|
|
def consts(t):
|
|
"""Yield a doctest-safe sequence of object reprs."""
|
|
for elt in t:
|
|
r = repr(elt)
|
|
if r.startswith("<code object"):
|
|
yield "<code object %s>" % elt.co_name
|
|
else:
|
|
yield r
|
|
|
|
def dump(co):
|
|
"""Print out a text representation of a code object."""
|
|
for attr in ["name", "argcount", "kwonlyargcount", "names", "varnames",
|
|
"cellvars", "freevars", "nlocals", "flags"]:
|
|
print("%s: %s" % (attr, getattr(co, "co_" + attr)))
|
|
print("consts:", tuple(consts(co.co_consts)))
|
|
|
|
# Needed for test_closure_injection below
|
|
# Defined at global scope to avoid implicitly closing over __class__
|
|
def external_getitem(self, i):
|
|
return f"Foreign getitem: {super().__getitem__(i)}"
|
|
|
|
class CodeTest(unittest.TestCase):
|
|
|
|
@cpython_only
|
|
def test_newempty(self):
|
|
import _testcapi
|
|
co = _testcapi.code_newempty("filename", "funcname", 15)
|
|
self.assertEqual(co.co_filename, "filename")
|
|
self.assertEqual(co.co_name, "funcname")
|
|
self.assertEqual(co.co_firstlineno, 15)
|
|
|
|
@cpython_only
|
|
def test_closure_injection(self):
|
|
# From https://bugs.python.org/issue32176
|
|
from types import FunctionType, CodeType
|
|
|
|
def create_closure(__class__):
|
|
return (lambda: __class__).__closure__
|
|
|
|
def new_code(c):
|
|
'''A new code object with a __class__ cell added to freevars'''
|
|
return CodeType(
|
|
c.co_argcount, c.co_kwonlyargcount, c.co_nlocals,
|
|
c.co_stacksize, c.co_flags, c.co_code, c.co_consts, c.co_names,
|
|
c.co_varnames, c.co_filename, c.co_name, c.co_firstlineno,
|
|
c.co_lnotab, c.co_freevars + ('__class__',), c.co_cellvars)
|
|
|
|
def add_foreign_method(cls, name, f):
|
|
code = new_code(f.__code__)
|
|
assert not f.__closure__
|
|
closure = create_closure(cls)
|
|
defaults = f.__defaults__
|
|
setattr(cls, name, FunctionType(code, globals(), name, defaults, closure))
|
|
|
|
class List(list):
|
|
pass
|
|
|
|
add_foreign_method(List, "__getitem__", external_getitem)
|
|
|
|
# Ensure the closure injection actually worked
|
|
function = List.__getitem__
|
|
class_ref = function.__closure__[0].cell_contents
|
|
self.assertIs(class_ref, List)
|
|
|
|
# Ensure the code correctly indicates it accesses a free variable
|
|
self.assertFalse(function.__code__.co_flags & inspect.CO_NOFREE,
|
|
hex(function.__code__.co_flags))
|
|
|
|
# Ensure the zero-arg super() call in the injected method works
|
|
obj = List([1, 2, 3])
|
|
self.assertEqual(obj[0], "Foreign getitem: 1")
|
|
|
|
def isinterned(s):
|
|
return s is sys.intern(('_' + s + '_')[1:-1])
|
|
|
|
class CodeConstsTest(unittest.TestCase):
|
|
|
|
def find_const(self, consts, value):
|
|
for v in consts:
|
|
if v == value:
|
|
return v
|
|
self.assertIn(value, consts) # raises an exception
|
|
self.fail('Should never be reached')
|
|
|
|
def assertIsInterned(self, s):
|
|
if not isinterned(s):
|
|
self.fail('String %r is not interned' % (s,))
|
|
|
|
def assertIsNotInterned(self, s):
|
|
if isinterned(s):
|
|
self.fail('String %r is interned' % (s,))
|
|
|
|
@cpython_only
|
|
def test_interned_string(self):
|
|
co = compile('res = "str_value"', '?', 'exec')
|
|
v = self.find_const(co.co_consts, 'str_value')
|
|
self.assertIsInterned(v)
|
|
|
|
@cpython_only
|
|
def test_interned_string_in_tuple(self):
|
|
co = compile('res = ("str_value",)', '?', 'exec')
|
|
v = self.find_const(co.co_consts, ('str_value',))
|
|
self.assertIsInterned(v[0])
|
|
|
|
@cpython_only
|
|
def test_interned_string_in_frozenset(self):
|
|
co = compile('res = a in {"str_value"}', '?', 'exec')
|
|
v = self.find_const(co.co_consts, frozenset(('str_value',)))
|
|
self.assertIsInterned(tuple(v)[0])
|
|
|
|
@cpython_only
|
|
def test_interned_string_default(self):
|
|
def f(a='str_value'):
|
|
return a
|
|
self.assertIsInterned(f())
|
|
|
|
@cpython_only
|
|
def test_interned_string_with_null(self):
|
|
co = compile(r'res = "str\0value!"', '?', 'exec')
|
|
v = self.find_const(co.co_consts, 'str\0value!')
|
|
self.assertIsNotInterned(v)
|
|
|
|
|
|
class CodeWeakRefTest(unittest.TestCase):
|
|
|
|
def test_basic(self):
|
|
# Create a code object in a clean environment so that we know we have
|
|
# the only reference to it left.
|
|
namespace = {}
|
|
exec("def f(): pass", globals(), namespace)
|
|
f = namespace["f"]
|
|
del namespace
|
|
|
|
self.called = False
|
|
def callback(code):
|
|
self.called = True
|
|
|
|
# f is now the last reference to the function, and through it, the code
|
|
# object. While we hold it, check that we can create a weakref and
|
|
# deref it. Then delete it, and check that the callback gets called and
|
|
# the reference dies.
|
|
coderef = weakref.ref(f.__code__, callback)
|
|
self.assertTrue(bool(coderef()))
|
|
del f
|
|
self.assertFalse(bool(coderef()))
|
|
self.assertTrue(self.called)
|
|
|
|
|
|
if check_impl_detail(cpython=True) and ctypes is not None:
|
|
py = ctypes.pythonapi
|
|
freefunc = ctypes.CFUNCTYPE(None,ctypes.c_voidp)
|
|
|
|
RequestCodeExtraIndex = py._PyEval_RequestCodeExtraIndex
|
|
RequestCodeExtraIndex.argtypes = (freefunc,)
|
|
RequestCodeExtraIndex.restype = ctypes.c_ssize_t
|
|
|
|
SetExtra = py._PyCode_SetExtra
|
|
SetExtra.argtypes = (ctypes.py_object, ctypes.c_ssize_t, ctypes.c_voidp)
|
|
SetExtra.restype = ctypes.c_int
|
|
|
|
GetExtra = py._PyCode_GetExtra
|
|
GetExtra.argtypes = (ctypes.py_object, ctypes.c_ssize_t,
|
|
ctypes.POINTER(ctypes.c_voidp))
|
|
GetExtra.restype = ctypes.c_int
|
|
|
|
LAST_FREED = None
|
|
def myfree(ptr):
|
|
global LAST_FREED
|
|
LAST_FREED = ptr
|
|
|
|
FREE_FUNC = freefunc(myfree)
|
|
FREE_INDEX = RequestCodeExtraIndex(FREE_FUNC)
|
|
|
|
class CoExtra(unittest.TestCase):
|
|
def get_func(self):
|
|
# Defining a function causes the containing function to have a
|
|
# reference to the code object. We need the code objects to go
|
|
# away, so we eval a lambda.
|
|
return eval('lambda:42')
|
|
|
|
def test_get_non_code(self):
|
|
f = self.get_func()
|
|
|
|
self.assertRaises(SystemError, SetExtra, 42, FREE_INDEX,
|
|
ctypes.c_voidp(100))
|
|
self.assertRaises(SystemError, GetExtra, 42, FREE_INDEX,
|
|
ctypes.c_voidp(100))
|
|
|
|
def test_bad_index(self):
|
|
f = self.get_func()
|
|
self.assertRaises(SystemError, SetExtra, f.__code__,
|
|
FREE_INDEX+100, ctypes.c_voidp(100))
|
|
self.assertEqual(GetExtra(f.__code__, FREE_INDEX+100,
|
|
ctypes.c_voidp(100)), 0)
|
|
|
|
def test_free_called(self):
|
|
# Verify that the provided free function gets invoked
|
|
# when the code object is cleaned up.
|
|
f = self.get_func()
|
|
|
|
SetExtra(f.__code__, FREE_INDEX, ctypes.c_voidp(100))
|
|
del f
|
|
self.assertEqual(LAST_FREED, 100)
|
|
|
|
def test_get_set(self):
|
|
# Test basic get/set round tripping.
|
|
f = self.get_func()
|
|
|
|
extra = ctypes.c_voidp()
|
|
|
|
SetExtra(f.__code__, FREE_INDEX, ctypes.c_voidp(200))
|
|
# reset should free...
|
|
SetExtra(f.__code__, FREE_INDEX, ctypes.c_voidp(300))
|
|
self.assertEqual(LAST_FREED, 200)
|
|
|
|
extra = ctypes.c_voidp()
|
|
GetExtra(f.__code__, FREE_INDEX, extra)
|
|
self.assertEqual(extra.value, 300)
|
|
del f
|
|
|
|
def test_free_different_thread(self):
|
|
# Freeing a code object on a different thread then
|
|
# where the co_extra was set should be safe.
|
|
f = self.get_func()
|
|
class ThreadTest(threading.Thread):
|
|
def __init__(self, f, test):
|
|
super().__init__()
|
|
self.f = f
|
|
self.test = test
|
|
def run(self):
|
|
del self.f
|
|
self.test.assertEqual(LAST_FREED, 500)
|
|
|
|
SetExtra(f.__code__, FREE_INDEX, ctypes.c_voidp(500))
|
|
tt = ThreadTest(f, self)
|
|
del f
|
|
tt.start()
|
|
tt.join()
|
|
self.assertEqual(LAST_FREED, 500)
|
|
|
|
def test_main(verbose=None):
|
|
from test import test_code
|
|
run_doctest(test_code, verbose)
|
|
tests = [CodeTest, CodeConstsTest, CodeWeakRefTest]
|
|
if check_impl_detail(cpython=True) and ctypes is not None:
|
|
tests.append(CoExtra)
|
|
run_unittest(*tests)
|
|
|
|
if __name__ == "__main__":
|
|
test_main()
|