"""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 unittest
import weakref
from test.support import run_doctest, run_unittest, cpython_only
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)))
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)
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)
def test_main(verbose=None):
from test import test_code
run_doctest(test_code, verbose)
run_unittest(CodeTest, CodeWeakRefTest)
if __name__ == "__main__":
test_main()