circuitpython/tests/basics/bytearray_slice_assign.py
Damien George acfbb9febd py/objarray: Fix amount of free space in array when doing slice assign.
Prior to this patch the amount of free space in an array (including
bytearray) was not being maintained correctly for the case of slice
assignment which changed the size of the array.  Under certain cases (as
encoded in the new test) it was possible that the array could grow beyond
its allocated memory block and corrupt the heap.

Fixes issue #4127.
2019-08-15 23:02:04 +10:00

69 lines
1.2 KiB
Python

try:
bytearray()[:] = bytearray()
except TypeError:
print("SKIP")
raise SystemExit
# test slices; only 2 argument version supported by MicroPython at the moment
x = bytearray(range(10))
# Assignment
l = bytearray(x)
l[1:3] = bytearray([10, 20])
print(l)
l = bytearray(x)
l[1:3] = bytearray([10])
print(l)
l = bytearray(x)
l[1:3] = bytearray()
print(l)
l = bytearray(x)
#del l[1:3]
print(l)
l = bytearray(x)
l[:3] = bytearray([10, 20])
print(l)
l = bytearray(x)
l[:3] = bytearray()
print(l)
l = bytearray(x)
#del l[:3]
print(l)
l = bytearray(x)
l[:-3] = bytearray([10, 20])
print(l)
l = bytearray(x)
l[:-3] = bytearray()
print(l)
l = bytearray(x)
#del l[:-3]
print(l)
# slice assignment that extends the array
b = bytearray(2)
b[2:] = bytearray(10)
print(b)
b = bytearray(10)
b[:-1] = bytearray(500)
print(len(b), b[0], b[-1])
# extension with self on RHS
b = bytearray(x)
b[4:] = b
print(b)
# Assignment of bytes to array slice
b = bytearray(2)
b[1:1] = b"12345"
print(b)
# Growth of bytearray via slice extension
b = bytearray(b'12345678')
b.append(57) # expand and add a bit of unused space at end of the bytearray
for i in range(400):
b[-1:] = b'ab' # grow slowly into the unused space
print(len(b), b)