From 12dd8df3756d58af2f4d1f54eefd90f1ce1e0dbe Mon Sep 17 00:00:00 2001 From: Damien George Date: Sat, 7 May 2016 21:18:17 +0100 Subject: [PATCH] py/objstr: Binary type of str/bytes for buffer protocol is 'B'. The type is an unsigned 8-bit value, since bytes objects are exactly that. And it's also sensible for unicode strings to return unsigned values when accessed in a byte-wise manner (CPython does not allow this). --- py/objstr.c | 2 +- tests/basics/memoryview2.py | 11 +++++++++++ 2 files changed, 12 insertions(+), 1 deletion(-) create mode 100644 tests/basics/memoryview2.py diff --git a/py/objstr.c b/py/objstr.c index d0d090b995..3d3845f4a4 100644 --- a/py/objstr.c +++ b/py/objstr.c @@ -1806,7 +1806,7 @@ mp_int_t mp_obj_str_get_buffer(mp_obj_t self_in, mp_buffer_info_t *bufinfo, mp_u GET_STR_DATA_LEN(self_in, str_data, str_len); bufinfo->buf = (void*)str_data; bufinfo->len = str_len; - bufinfo->typecode = 'b'; + bufinfo->typecode = 'B'; // bytes should be unsigned, so should unicode byte-access return 0; } else { // can't write to a string diff --git a/tests/basics/memoryview2.py b/tests/basics/memoryview2.py new file mode 100644 index 0000000000..5b2a535f9a --- /dev/null +++ b/tests/basics/memoryview2.py @@ -0,0 +1,11 @@ +# test memoryview accessing maximum values for signed/unsigned elements + +from array import array + +print(list(memoryview(b'\x7f\x80\x81\xff'))) +print(list(memoryview(array('b', [0x7f, -0x80])))) +print(list(memoryview(array('B', [0x7f, 0x80, 0x81, 0xff])))) +print(list(memoryview(array('h', [0x7f00, -0x8000])))) +print(list(memoryview(array('H', [0x7f00, 0x8000, 0x8100, 0xffff])))) +print(list(memoryview(array('i', [0x7f000000, -0x80000000])))) +print(list(memoryview(array('I', [0x7f000000, 0x80000000, 0x81000000, 0xffffffff]))))