py: Allow to pass in read-only buffers to viper and inline-asm funcs.

Fixes #4936.

1 files changed, 10 insertions, 0 deletions

diff --git a/tests/micropython/viper_addr.py b/tests/micropython/viper_addr.py
index cd953ce07..0d8efb90b 100644
--- a/tests/micropython/viper_addr.py
+++ b/tests/micropython/viper_addr.py
@@ -9,6 +9,13 @@ def memset(dest:ptr8, c:int, n:int):
     for i in range(n):
         dest[i] = c
 
+@micropython.viper
+def memsum(src:ptr8, n:int) -> int:
+    s = 0
+    for i in range(n):
+        s += src[i]
+    return s
+
 # create array and get its address
 ar = bytearray('0000')
 addr = get_addr(ar)
@@ -27,3 +34,6 @@ print(ar)
 # pass direct pointer to array buffer, with offset
 memset(addr + 2, ord('3'), len(ar) - 2)
 print(ar)
+
+# pass a read-only bytes object in
+print(memsum(b'\x01\x02\x03\x04', 4))