Fix ArrayishVec::drain implementation

The end bound was off by one

src/arrayish_vec.rs

@@ -200,8 +200,8 @@ impl<A: Arrayish> ArrayishVec<A> {
       Bound::Unbounded => 0,
     };
     let end = match range.end_bound() {
-      Bound::Included(x) => *x,
-      Bound::Excluded(x) => x - 1,
+      Bound::Included(x) => x + 1,
+      Bound::Excluded(x) => *x,
       Bound::Unbounded => self.len,
     };
     assert!(

tests/basic_tests.rs

@@ -1,6 +1,7 @@
 #![allow(bad_style)]
 
 use tinyvec::*;
+use std::iter::FromIterator;
 
 #[test]
 fn test_a_vec() {
@@ -121,3 +122,32 @@ fn ArrayishVec_remove() {
   assert_eq!(av.remove(1), 2);
   assert_eq!(&av[..], &[1, 3][..]);
 }
+
+#[test]
+fn ArrayishVec_drain() {
+  let mut av: ArrayishVec<[i32; 10]> = Default::default();
+  av.push(1);
+  av.push(2);
+  av.push(3);
+
+  assert_eq!(Vec::from_iter(av.clone().drain(..)), vec![1, 2, 3]);
+
+  assert_eq!(Vec::from_iter(av.clone().drain(..2)), vec![1, 2]);
+  assert_eq!(Vec::from_iter(av.clone().drain(..3)), vec![1, 2, 3]);
+
+  assert_eq!(Vec::from_iter(av.clone().drain(..=1)), vec![1, 2]);
+  assert_eq!(Vec::from_iter(av.clone().drain(..=2)), vec![1, 2, 3]);
+
+  assert_eq!(Vec::from_iter(av.clone().drain(0..)), vec![1, 2, 3]);
+  assert_eq!(Vec::from_iter(av.clone().drain(1..)), vec![2, 3]);
+
+  assert_eq!(Vec::from_iter(av.clone().drain(0..2)), vec![1, 2]);
+  assert_eq!(Vec::from_iter(av.clone().drain(0..3)), vec![1, 2, 3]);
+  assert_eq!(Vec::from_iter(av.clone().drain(1..2)), vec![2]);
+  assert_eq!(Vec::from_iter(av.clone().drain(1..3)), vec![2, 3]);
+
+  assert_eq!(Vec::from_iter(av.clone().drain(0..=1)), vec![1, 2]);
+  assert_eq!(Vec::from_iter(av.clone().drain(0..=2)), vec![1, 2, 3]);
+  assert_eq!(Vec::from_iter(av.clone().drain(1..=1)), vec![2]);
+  assert_eq!(Vec::from_iter(av.clone().drain(1..=2)), vec![2, 3]);
+}