Gecko [ edgpens.lpkmn.gov.my ]

Name	Size	Permission
__pycache__	[ DIR ]	drwxrwxrwx
__init__.py	461 B	-rw-rw-rw-
__main__.py	72 B	-rw-rw-rw-
test_anon.py	2.55 KB	-rw-rw-rw-
test_array_in_pointer.py	1.76 KB	-rw-rw-rw-
test_arrays.py	7.56 KB	-rw-rw-rw-
test_as_parameter.py	6.98 KB	-rw-rw-rw-
test_bitfields.py	10.4 KB	-rw-rw-rw-
test_buffers.py	2.62 KB	-rw-rw-rw-
test_bytes.py	2 KB	-rw-rw-rw-
test_byteswap.py	11.45 KB	-rw-rw-rw-
test_callbacks.py	10.64 KB	-rw-rw-rw-
test_cast.py	3.74 KB	-rw-rw-rw-
test_cfuncs.py	7.71 KB	-rw-rw-rw-
test_checkretval.py	1004 B	-rw-rw-rw-
test_delattr.py	554 B	-rw-rw-rw-
test_errno.py	2.19 KB	-rw-rw-rw-
test_find.py	4.48 KB	-rw-rw-rw-
test_frombuffer.py	5.23 KB	-rw-rw-rw-
test_funcptr.py	4.06 KB	-rw-rw-rw-
test_functions.py	12.59 KB	-rw-rw-rw-
test_incomplete.py	1.04 KB	-rw-rw-rw-
test_init.py	1.05 KB	-rw-rw-rw-
test_internals.py	2.67 KB	-rw-rw-rw-
test_keeprefs.py	4.11 KB	-rw-rw-rw-
test_libc.py	1.01 KB	-rw-rw-rw-
test_loading.py	7.15 KB	-rw-rw-rw-
test_macholib.py	2.14 KB	-rw-rw-rw-
test_memfunctions.py	3.29 KB	-rw-rw-rw-
test_numbers.py	9.54 KB	-rw-rw-rw-
test_objects.py	1.7 KB	-rw-rw-rw-
test_parameters.py	9.59 KB	-rw-rw-rw-
test_pep3118.py	8.54 KB	-rw-rw-rw-
test_pickling.py	2.25 KB	-rw-rw-rw-
test_pointers.py	7.29 KB	-rw-rw-rw-
test_prototypes.py	6.9 KB	-rw-rw-rw-
test_python_api.py	2.79 KB	-rw-rw-rw-
test_random_things.py	2.84 KB	-rw-rw-rw-
test_refcounts.py	2.61 KB	-rw-rw-rw-
test_repr.py	871 B	-rw-rw-rw-
test_returnfuncptrs.py	2.89 KB	-rw-rw-rw-
test_simplesubclasses.py	1.31 KB	-rw-rw-rw-
test_sizes.py	837 B	-rw-rw-rw-
test_slicing.py	6.05 KB	-rw-rw-rw-
test_stringptr.py	2.61 KB	-rw-rw-rw-
test_strings.py	7.36 KB	-rw-rw-rw-
test_struct_fields.py	2.64 KB	-rw-rw-rw-
test_structures.py	27.58 KB	-rw-rw-rw-
test_unaligned_structures.py	1.16 KB	-rw-rw-rw-
test_unicode.py	2.01 KB	-rw-rw-rw-
test_values.py	3.88 KB	-rw-rw-rw-
test_varsize_struct.py	1.85 KB	-rw-rw-rw-
test_win32.py	5.04 KB	-rw-rw-rw-
test_wintypes.py	1.41 KB	-rw-rw-rw-

Name

Size

Permission

Action

__pycache__

[ DIR ]

drwxrwxrwx

__init__.py

461 B

-rw-rw-rw-

__main__.py

72 B

-rw-rw-rw-

test_anon.py

2.55 KB

-rw-rw-rw-

test_array_in_pointer.py

1.76 KB

-rw-rw-rw-

test_arrays.py

7.56 KB

-rw-rw-rw-

test_as_parameter.py

6.98 KB

-rw-rw-rw-

test_bitfields.py

10.4 KB

-rw-rw-rw-

test_buffers.py

2.62 KB

-rw-rw-rw-

test_bytes.py

2 KB

-rw-rw-rw-

test_byteswap.py

11.45 KB

-rw-rw-rw-

test_callbacks.py

10.64 KB

-rw-rw-rw-

test_cast.py

3.74 KB

-rw-rw-rw-

test_cfuncs.py

7.71 KB

-rw-rw-rw-

test_checkretval.py

1004 B

-rw-rw-rw-

test_delattr.py

554 B

-rw-rw-rw-

test_errno.py

2.19 KB

-rw-rw-rw-

test_find.py

4.48 KB

-rw-rw-rw-

test_frombuffer.py

5.23 KB

-rw-rw-rw-

test_funcptr.py

4.06 KB

-rw-rw-rw-

test_functions.py

12.59 KB

-rw-rw-rw-

test_incomplete.py

1.04 KB

-rw-rw-rw-

test_init.py

1.05 KB

-rw-rw-rw-

test_internals.py

2.67 KB

-rw-rw-rw-

test_keeprefs.py

4.11 KB

-rw-rw-rw-

test_libc.py

1.01 KB

-rw-rw-rw-

test_loading.py

7.15 KB

-rw-rw-rw-

test_macholib.py

2.14 KB

-rw-rw-rw-

test_memfunctions.py

3.29 KB

-rw-rw-rw-

test_numbers.py

9.54 KB

-rw-rw-rw-

test_objects.py

1.7 KB

-rw-rw-rw-

test_parameters.py

9.59 KB

-rw-rw-rw-

test_pep3118.py

8.54 KB

-rw-rw-rw-

test_pickling.py

2.25 KB

-rw-rw-rw-

test_pointers.py

7.29 KB

-rw-rw-rw-

test_prototypes.py

6.9 KB

-rw-rw-rw-

test_python_api.py

2.79 KB

-rw-rw-rw-

test_random_things.py

2.84 KB

-rw-rw-rw-

test_refcounts.py

2.61 KB

-rw-rw-rw-

test_repr.py

871 B

-rw-rw-rw-

test_returnfuncptrs.py

2.89 KB

-rw-rw-rw-

test_simplesubclasses.py

1.31 KB

-rw-rw-rw-

test_sizes.py

837 B

-rw-rw-rw-

test_slicing.py

6.05 KB

-rw-rw-rw-

test_stringptr.py

2.61 KB

-rw-rw-rw-

test_strings.py

7.36 KB

-rw-rw-rw-

test_struct_fields.py

2.64 KB

-rw-rw-rw-

test_structures.py

27.58 KB

-rw-rw-rw-

test_unaligned_structures.py

1.16 KB

-rw-rw-rw-

test_unicode.py

2.01 KB

-rw-rw-rw-

test_values.py

3.88 KB

-rw-rw-rw-

test_varsize_struct.py

1.85 KB

-rw-rw-rw-

test_win32.py

5.04 KB

-rw-rw-rw-

test_wintypes.py

1.41 KB

-rw-rw-rw-

Code Editor : test_objects.py

r'''
This tests the '_objects' attribute of ctypes instances.  '_objects'
holds references to objects that must be kept alive as long as the
ctypes instance, to make sure that the memory buffer is valid.

WARNING: The '_objects' attribute is exposed ONLY for debugging ctypes itself,
it MUST NEVER BE MODIFIED!

'_objects' is initialized to a dictionary on first use, before that it
is None.

Here is an array of string pointers:

>>> from ctypes import *
>>> array = (c_char_p * 5)()
>>> print(array._objects)
None
>>>

The memory block stores pointers to strings, and the strings itself
assigned from Python must be kept.

>>> array[4] = b'foo bar'
>>> array._objects
{'4': b'foo bar'}
>>> array[4]
b'foo bar'
>>>

It gets more complicated when the ctypes instance itself is contained
in a 'base' object.

>>> class X(Structure):
...     _fields_ = [("x", c_int), ("y", c_int), ("array", c_char_p * 5)]
...
>>> x = X()
>>> print(x._objects)
None
>>>

The'array' attribute of the 'x' object shares part of the memory buffer
of 'x' ('_b_base_' is either None, or the root object owning the memory block):

>>> print(x.array._b_base_) # doctest: +ELLIPSIS
<ctypes.test.test_objects.X object at 0x...>
>>>

>>> x.array[0] = b'spam spam spam'
>>> x._objects
{'0:2': b'spam spam spam'}
>>> x.array._b_base_._objects
{'0:2': b'spam spam spam'}
>>>

'''

import unittest, doctest

import ctypes.test.test_objects

class TestCase(unittest.TestCase):
    def test(self):
        failures, tests = doctest.testmod(ctypes.test.test_objects)
        self.assertFalse(failures, 'doctests failed, see output above')

if __name__ == '__main__':
    doctest.testmod(ctypes.test.test_objects)

${this.title}

Code Editor : test_objects.py