[pypy-dev] Looking into numpy ndarray.flags.writeable

[Eli Stevens (Gmail)]

More questions!  :)

When I run

    pypy> /usr/bin/python bin/pyinteractive.py

I get to a (presumably interpreted, given the startup time) pypy
prompt, but I cannot import numpy. Is the intent that I somehow
install numpy into the source checkout's site-packages directory (the
one listed in sys.path from that interpreted pypy prompt)?

Also, it's pretty clear that when running the tests that "import
numpy" just gets the numpy from the base interpreter, not from the
micronumpy included in the pypy source. Is it possible to run the
numpy tests without doing a full translation?

Thanks,
Eli

On Thu, May 19, 2016 at 1:36 PM, Eli Stevens (Gmail)
<wickedgrey at gmail.com> wrote:
> Looks like I need to do something along the lines of:
>
>     def descr_set_writeable(self, space, w_value):
>         if space.is_true(w_value) != bool(self.flags & NPY.ARRAY_WRITEABLE):
>             self.flags ^= NPY.ARRAY_WRITEABLE
>
> (Though I probably need more robust checking to see if the flag *can*
> be turned off)
>
>     def descr_setitem(self, space, w_item, w_value):
>         # This function already exists, but just contains the last
> line with the raise
>         key = space.str_w(w_item)
>         value = space.bool_w(w_value)
>         if key == "W" or key == "WRITEABLE":
>             return self.descr_set_writeable(space, value)
>         raise oefmt(space.w_KeyError, "Unknown flag")
>
> ...
>     writeable = GetSetProperty(W_FlagsObject.descr_get_writeable,
> W_FlagsObject.descr_set_writeable),
>
> However I'm not entirely confident about things like space.bool_w,
> etc. I've read http://doc.pypy.org/en/latest/objspace.html but am
> still working on internalizing it.
>
> Setting the GetSetProperty still results in the TypeError, which makes
> me wonder how to tell if I'm getting the right flagsobj.py. I don't
> think that I am. The results of the tests should be the same no matter
> what python interpreter I'm using, correct? Would running the tests
> with a virtualenv that has a stock pypy/numpy installed cause issues?
> What if the virtualenv is cpython?
>
> When I run py.test, I see:
>
> pytest-2.5.2 from /Users/elis/edit/play/pypy/pytest.pyc
>
> Which looks correct (.../play/pypy is my source checkout). But I get
> the same thing when using cpython to run test_all.py, and there the
> test passes, so I don't think it's indicative. When I print out
> np.__file__ inside the test, I get
>
>     /Users/elis/venv/droidblue-pypy/site-packages/numpy/__init__.pyc
>
> Which is the pypy venv I am using to run the tests in the first place,
> but I'm not sure what the on-disk relationship between numpy and
> micronumpy actually is. Is there a way from the test_flagobjs.py file
> to determine what the on-disk location of micronumpy is?
>
> I strongly suspect I've got something basic wrong. I also think that
> the information at
> http://doc.pypy.org/en/latest/getting-started-dev.html#running-pypy-s-unit-tests
> and http://doc.pypy.org/en/latest/coding-guide.html#command-line-tool-test-all
> conflict somewhat, or are at least unclear as to which approach is the
> right way in what situation. I'll attempt to clarify whatever it is
> that's tripping me up once I've got it sorted out.
>
> Some other questions I have, looking at micornumpy/concrete.py line 37:
>
> class BaseConcreteArray(object):
>     _immutable_fields_ = ['dtype?', 'storage', 'start', 'size', 'shape[*]',
>                           'strides[*]', 'backstrides[*]', 'order', 'gcstruct',
>                           'flags']
>     start = 0
>     parent = None
>     flags = 0
>
> Does that immutable status cascade down into the objects, or is that
> saying only that myInstance.flags cannot be reassigned (but
> myInstance.flags.foo = 3 is fine)?
>
> interpreter/typedef.py 221:
>
> @specialize.arg(0)
> def make_objclass_getter(tag, func, cls):
>     if func and hasattr(func, 'im_func'):
>         assert not cls or cls is func.im_class
>         cls = func.im_class
>     return _make_objclass_getter(cls)
>
> What's the purpose of the tag argument? It doesn't seem to be used
> here or in _make_descr_typecheck_wrapper, both of which are called
> from GetSetProperty init. Based on docstrings on _Specialize, it seems
> like they might be JIT hints. Is that correct?
>
> Matti: If it's okay, I'd like to keep the discussion on the list, as
> I've actively searched through discussions here to avoid asking
> questions a second time. Hopefully this thread can help the next
> person.
>
> Sorry for the mega-post; thanks for reading.
> Eli
>
> On Thu, May 19, 2016 at 8:23 AM, Armin Rigo <arigo at tunes.org> wrote:
>> Hi Eli,
>>
>> On 19 May 2016 at 08:58, Eli Stevens (Gmail) <wickedgrey at gmail.com> wrote:
>>> I've got a pypy clone and checkout, and have added TestFlags. When I
>>> run it, I see:
>>>
>>>>       a.flags.writeable = False
>>> E       TypeError: readonly attribute
>>>
>>> But nothing that looks like it should raise a TypeError in either of:
>>
>> Grep for 'writable'.  You'll see that it is defined as a
>> GetSetProperty() with a getter but no setter so far.
>>
>>
>> A bientôt,
>>
>> Armin.