Fix a fencepost error in CommandArguments

Change-Id: I8030f2e887288e9409cafe027606c67ca5d8e92d
Reviewed-on: http://gerrit.dmdirc.com/925
Reviewed-by: Gregory Holmes <greg@dmdirc.com>
Automatic-Compile: DMDirc Local Commits <dmdirc@googlemail.com>

src/com/dmdirc/commandparser/CommandArguments.java

@@ -159,7 +159,9 @@ public class CommandArguments {
      * @return A String representation of the requested words
      */
     public String getWordsAsString(final int start) {
-        return getWordsAsString(start, words.length);
+        parse();
+        
+        return getWordsAsString(start, words.length - 1);
     }
 
     /**
@@ -172,10 +174,10 @@ public class CommandArguments {
      */
     @Precondition("Start index is less than or equal to end index")
     public String getWordsAsString(final int start, final int end) {
-        Logger.assertTrue(start <= end);
+        Logger.assertTrue(start <= end + 1);
 
         final Pattern pattern = Pattern.compile("(\\S+\\s*){" + (start) + "}"
-                + "((\\S+\\s*){" + (end - start) + "}).*?");
+                + "((\\S+\\s*){" + Math.max(0, end - start) + "}\\S+).*?");
         final Matcher matcher = pattern.matcher(line);
 
         return matcher.matches() ? matcher.group(2) : "";