Merge pull request #2387 from carbotaniuman/magic-methods

use unsigned abs to avoid overflow

extra_tests/snippets/bytearray.py

@@ -1,5 +1,6 @@
 from testutils import assert_raises
 import pickle
+import sys
 
 # new
 assert bytearray([1, 2, 3])
@@ -753,4 +754,8 @@ b = pickle.loads(pickle.dumps(a, 4))
 assert type(a) == type(b)
 assert a.x == b.x
 assert a.y == b.y
-assert a == b
+assert a == b
+
+a = bytearray()
+for i in range(-1, 2, 1):
+    assert_raises(IndexError, lambda: a[-sys.maxsize - i], _msg='bytearray index out of range')

vm/src/sliceable.rs

@@ -391,7 +391,7 @@ impl TryFromObject for SequenceIndex {
 // Use PySliceableSequence::wrap_index for implementors
 pub(crate) fn wrap_index(p: isize, len: usize) -> Option<usize> {
     let neg = p.is_negative();
-    let p = p.abs().to_usize()?;
+    let p = p.wrapping_abs() as usize;
     if neg {
         len.checked_sub(p)
     } else if p >= len {