rename variable and update comments

re https://github.com/lampepfl/dotty/pull/16011/files#r976507277

Author: mpollmeier

compiler/src/dotty/tools/repl/Rendering.scala

@@ -73,18 +73,15 @@ private[repl] class Rendering(parentClassLoader: Option[ClassLoader] = None):
       myClassLoader
     }
 
-  /** Used to elide long output in replStringOf.
-   *
-   * TODO: Perhaps implement setting scala.repl.maxprintstring as in Scala 2, but
-   * then this bug will surface, so perhaps better not?
-   * https://github.com/scala/bug/issues/12337
-   */
+  /** Used to elide long output in replStringOf. */
   private[repl] def truncate(str: String)(using ctx: Context): String =
-    val maxPrintElements = ctx.settings.VreplMaxPrintElements.valueIn(ctx.settingsState)
+    // FIXME introduce a new setting `-Vrepl-max-print-characters` that allows to limit truncation by character properly
+    // see https://github.com/lampepfl/dotty/pull/16011#issuecomment-1245099657
+    val maxPrintCharacters = ctx.settings.VreplMaxPrintElements.valueIn(ctx.settingsState)
     val showTruncated = " ... large output truncated, print value to show all"
     val ncp = str.codePointCount(0, str.length) // to not cut inside code point
-    if ncp <= maxPrintElements then str
-    else str.substring(0, str.offsetByCodePoints(0, maxPrintElements - 1)) + showTruncated
+    if ncp <= maxPrintCharacters then str
+    else str.substring(0, str.offsetByCodePoints(0, maxPrintCharacters - 1)) + showTruncated
 
   /** Return a String representation of a value we got from `classLoader()`. */
   private[repl] def replStringOf(value: Object)(using Context): String =