WIP: add IndexList::move_to_last to maintain ListIndex

src/lib.rs

@@ -564,6 +564,16 @@ impl<T> IndexList<T> {
         }
         elem_opt
     }
+    /// Move the element at the index to the end.
+    /// The index remains the same.
+    pub fn move_to_last(&mut self, index: ListIndex) {
+        if self.is_index_used(index) {
+            // unlink where it is
+            self.linkout_used(index);
+            // insert it as last
+            self.linkin_last(index);
+        }
+    }
     /// Create a new iterator over all the elements.
     ///
     /// Example:

tests/test.rs

@@ -60,6 +60,7 @@ fn test_instantiate() {
     list.split(null);
     list.trim_safe();
     list.trim_swap();
+    list.move_to_last(ListIndex::new())
 }
 #[test]
 fn basic_insert_remove() {