[BUG] crash deleting element of ulab array

[jepler]

Describe the bug version 6.0.12-2D-c

The following python code crashes:

from ulab import numpy as np
n=np.array([0])
del n[0]

To Reproduce I run the above code sample on micropython-2 built to run on a host computer

Expected behavior standard Python numpy throws an exception: ValueError: cannot delete array elements

[jepler]

should also check slice deletion for similar problem

[v923z]

OK, but is this an issue in ulab as such, or is something in micropython amiss?

[jepler]

The site of the crash is

0x0000555555584a03 in ndarray_from_mp_obj (obj=0x0, 
    other_type=other_type@entry=0 '\000')
    at /home/jepler/src/ulab/code/ndarray.c:1696
1696        if(mp_obj_is_int(obj)) {
(gdb) where
#0  0x0000555555584a03 in ndarray_from_mp_obj (obj=0x0, 
    other_type=other_type@entry=0 '\000')
    at /home/jepler/src/ulab/code/ndarray.c:1696
#1  0x0000555555584e66 in ndarray_subscr (self_in=0x7ffff7a4e360, index=0x1, 
    value=<optimized out>) at /home/jepler/src/ulab/code/ndarray.c:1446
#2  0x00005555555b4a2e in mp_obj_subscr (base=0x7ffff7a4e360, index=0x1, 
    value=0x0) at ../../py/obj.c:538

A value of MP_OBJ_NULL (0 in this build) is used with the subscr method to delete. I think the proper fix for this is in ulab and raises an error when the argument to ndarray_subscr is MP_OBJ_NULL.

[v923z]

@jepler Thanks for raising the issue and the suggestion!

Fixed by https://github.com/v923z/micropython-ulab/pull/619.

[jepler]

Thanks for the fix