Apply suggestions from code review

Co-authored-by: Nicolas Stucki <nicolas.stucki@gmail.com>
Co-authored-by: Sébastien Doeraene <sjrdoeraene@gmail.com>

Author: 3 people

library/src/scala/util/boundary.scala

@@ -12,7 +12,7 @@ import control.ControlException
  *      The `Break` exception class extends `ControlException` which is a regular
  *      `RuntimeException`, optimized so that stack trace generation is suppressed.
  *    - Better performance: breaks to enclosing scopes in the same method can
- *      be rwritten to jumps.
+ *      be rewritten to jumps.
  */
 object boundary:
 

tests/run/breaks.scala

@@ -11,10 +11,10 @@ object Test {
   def takeUntil(xs: List[Int], elem: Int) =
     boundary:
       var buf = new ListBuffer[Int]
-      for x <- xs yield
+      for x <- xs do
         if x == elem then break(buf.toList)
         buf += x
-        x
+      xs
 
   trait Animal
   object Dog extends Animal