Cull extraneous whitespace.

One last flurry with the broom before I leave you slobs to code
in your own filth. Eliminated all the trailing whitespace I
could manage, with special prejudice reserved for the test cases
which depended on the preservation of trailing whitespace.

Was reminded I cannot figure out how to eliminate the trailing
space on the "scala> " prompt in repl transcripts. At least
reduced the number of such empty prompts by trimming transcript
code on the way in.

Routed ConsoleReporter's "printMessage" through a trailing
whitespace stripping method which might help futureproof
against the future of whitespace diseases. Deleted the up-to-40
lines of trailing whitespace found in various library files.

It seems like only yesterday we performed whitespace surgery
on the whole repo. Clearly it doesn't stick very well. I suggest
it would work better to enforce a few requirements on the way in.

1 files changed, 24 insertions, 8 deletions

diff --git a/src/reflect/scala/reflect/internal/util/StringOps.scala b/src/reflect/scala/reflect/internal/util/StringOps.scala
index 4d98a344d8..14f349f502 100644
--- a/src/reflect/scala/reflect/internal/util/StringOps.scala
+++ b/src/reflect/scala/reflect/internal/util/StringOps.scala
@@ -7,7 +7,11 @@
 \*                                                                      */
 
 package scala
-package reflect.internal.util
+package reflect
+package internal
+package util
+
+import scala.compat.Platform.EOL
 
 /** This object provides utility methods to extract elements
  *  from Strings.
@@ -18,14 +22,26 @@ package reflect.internal.util
 trait StringOps {
   def oempty(xs: String*)        = xs filterNot (x => x == null || x == "")
   def ojoin(xs: String*): String = oempty(xs: _*) mkString " "
-  def longestCommonPrefix(xs: List[String]): String = {
-    if (xs.isEmpty || xs.contains("")) ""
-    else xs.head.head match {
-      case ch =>
-        if (xs.tail forall (_.head == ch)) "" + ch + longestCommonPrefix(xs map (_.tail))
-        else ""
-    }
+  def longestCommonPrefix(xs: List[String]): String = xs match {
+    case Nil                  => ""
+    case xs if xs contains "" => ""
+    case x :: xs             =>
+      val ch = x charAt 0
+      if (xs exists (_.head != ch)) ""
+      else "" + ch + longestCommonPrefix(xs map (_ substring 1))
+  }
+  /** Like String#trim, but trailing whitespace only.
+   */
+  def trimTrailingSpace(s: String): String = {
+    var end = s.length
+    while (end > 0 && s.charAt(end - 1).isWhitespace)
+      end -= 1
+
+    if (end == s.length) s
+    else s.substring(0, end)
   }
+  /** Breaks the string into lines and strips each line before reassembling. */
+  def trimAllTrailingSpace(s: String): String = s.lines map trimTrailingSpace mkString EOL
 
   def decompose(str: String, sep: Char): List[String] = {
     def ws(start: Int): List[String] =