diff --git a/src/extensions/sequence.rs b/src/extensions/sequence.rs
index 08a7484..bbed765 100644
--- a/src/extensions/sequence.rs
+++ b/src/extensions/sequence.rs
@@ -852,11 +852,11 @@ pub trait Sequence<Item> {
   /// ```
   /// use cantrip::*;
   ///
-  /// let a = vec![-1, 4, 0, 1];
+  /// let a = vec![1, 2, 3];
   ///
   /// assert_eq!(
-  ///   a.map_while(|x| 16_i32.checked_div(*x)),
-  ///   vec![-16, 4]
+  ///   a.map_while(|&x| if x < 3 { Some(x + 1) } else { None }),
+  ///   vec![2, 3]
   /// );
   /// ```
   ///
@@ -868,11 +868,11 @@ pub trait Sequence<Item> {
   /// ```
   /// use cantrip::*;
   ///
-  /// let a = vec![-1, 4, 0, 1];
+  /// let a = vec![1, 2, 3];
   ///
   /// assert_eq!(
-  ///   a.map(|x| 16_i32.checked_div(*x)).take_while(|x| x.is_some()).map(|x| x.unwrap()),
-  ///   vec![-16, 4]
+  ///   a.map(|&x| if x < 3 { Some(x + 1) } else { None }).take_while(|x| x.is_some()).map(|x| x.unwrap()),
+  ///   vec![2, 3]
   /// );
   /// ```
   fn map_while<B>(&self, predicate: impl FnMut(&Item) -> Option<B>) -> Self::This<B>;
@@ -887,7 +887,7 @@ pub trait Sequence<Item> {
   /// assert_eq!(
   ///   a.merge(vec![0, 4, 5]),
   ///   vec![0, 1, 2, 3, 4, 5]
-  ///   );
+  /// );
   /// ```
   fn merge(self, elements: impl IntoIterator<Item = Item>) -> Self
   where
diff --git a/tests/extensions/sequence.rs b/tests/extensions/sequence.rs
index dfe78dc..b8bc1b9 100644
--- a/tests/extensions/sequence.rs
+++ b/tests/extensions/sequence.rs
@@ -15,6 +15,7 @@ where
     + Iterable<Item<'a> = &'a i64>
     + Clone
     + Equal
+    + UnwindSafe
     + Debug
     + 'a,
   for<'c> &'c C: UnwindSafe,
@@ -245,6 +246,42 @@ where
   // assert_seq_equal(a.intersperse_with(3, || 0), vec![1, 2, 3]);
   // assert_seq_equal(e.intersperse_with(1, || 0), vec![]);
 
+  // map_while - FIXME - implement test
+  // assert_seq_equal(a.map_while(|&x| if x < 2 { Some(x + 1) } else { None }), vec![2, 3]);
+  // assert_seq_equal(e.map_while(|&x| if x < 2 { Some(x + 1) } else { None }), vec![]);
+
+  // merge
+  let a = a_source.clone();
+  let e = e_source.clone();
+  assert_seq_equal(a.merge(vec![0, 4, 5]), vec![0, 1, 2, 3, 4, 5]);
+  assert_seq_equal(e.merge(vec![1]), vec![1]);
+  let e = e_source.clone();
+  assert_seq_equal(e.merge(vec![]), vec![]);
+
+  // merge_by
+  let a = a_source.clone();
+  let e = e_source.clone();
+  assert_seq_equal(a.merge_by(vec![0, 4, 5], |l, r| l.cmp(r)), vec![0, 1, 2, 3, 4, 5]);
+  assert_seq_equal(e.merge_by(vec![1], |l, r| l.cmp(r)), vec![1]);
+  let e = e_source.clone();
+  assert_seq_equal(e.merge_by(vec![], |l, r| l.cmp(r)), vec![]);
+
+  // move_at
+  let a = a_source.clone();
+  let e = e_source.clone();
+  assert_seq_equal(a.move_at(0, 2), vec![2, 3, 1]);
+  let a = a_source.clone();
+  assert_seq_equal(a.move_at(2, 1), vec![1, 3, 2]);
+  let a = a_source.clone();
+  assert_seq_equal(a.move_at(1, 1), vec![1, 2, 3]);
+  assert!(panic::catch_unwind(|| { e.move_at(0, 0) }).is_err());
+
+  // pad_left - FIXME - implement test
+  // let a = a_source.clone();
+  // let e = e_source.clone();
+  // assert_seq_equal(a.pad_left(5, 4), vec![4, 4, 1, 2, 3]);
+  // assert_seq_equal(e.pad_left(1, 1), vec![1]);
+
   // // rev
   // assert_equal(repeated.clone().rev(), vec![3, 2, 2, 1]);
   // assert_equal(empty.clone().rev(), vec![]);
diff --git a/tests/extensions/traits.rs b/tests/extensions/traits.rs
index 0495445..83bcacd 100644
--- a/tests/extensions/traits.rs
+++ b/tests/extensions/traits.rs
@@ -62,6 +62,7 @@ where
     + Extend<i64>
     + Clone
     + Equal
+    + UnwindSafe
     + Debug
     + 'a,
   <C as Collectible<i64>>::This<i64>: FromIterator<i64> + Default + Extend<i64> + Equal + Debug,
@@ -89,6 +90,7 @@ where
     + Extend<i64>
     + Clone
     + Equal
+    + UnwindSafe
     + Debug
     + 'a,
   <C as Collectible<i64>>::This<i64>: FromIterator<i64> + Default + Extend<i64> + Equal + Debug,