StringContext#checkLengths reports bad args count

Since interpolator args are of type Any, it's easy
to write s(args) instead of s(args: _*).  I wonder
if Xlint would have warned me about that.

1 files changed, 2 insertions, 1 deletions

diff --git a/src/library/scala/StringContext.scala b/src/library/scala/StringContext.scala
index 42fb2f36e8..70f95750da 100644
--- a/src/library/scala/StringContext.scala
+++ b/src/library/scala/StringContext.scala
@@ -59,7 +59,8 @@ case class StringContext(parts: String*) {
    */
   def checkLengths(args: Seq[Any]): Unit =
     if (parts.length != args.length + 1)
-      throw new IllegalArgumentException("wrong number of arguments for interpolated string")
+      throw new IllegalArgumentException("wrong number of arguments ("+ args.length
+        +") for interpolated string with "+ parts.length +" parts")
 
 
   /** The simple string interpolator.