patching up the lexer and adding a test with trailing whitespace (it was too string for trailing whitespace before)

lib/coffee_script/lexer.rb

@@ -27,7 +27,7 @@ module CoffeeScript
     COMMENT    = /\A((#[^\n]*\s*)+)/m
     CODE       = /\A(=>)/
     REGEX      = /\A(\/(.*?)[^\\]\/[imgy]{0,4})/
-    MULTI_DENT = /\A((\n+[ \t]*)+)/
+    MULTI_DENT = /\A((\n+([ \t]*(?=\S)))+)/
     LAST_DENT  = /\n+([ \t]*)\Z/
 
     # Token cleaning regexes.

test/fixtures/execution/test_calling_super.coffee

@@ -6,12 +6,12 @@ FirstChild: =>
 FirstChild extends Base
 FirstChild.prototype.func: string =>
   super('one/') + string
-
+     
 SecondChild: =>
 SecondChild extends FirstChild
 SecondChild.prototype.func: string =>
   super('two/') + string
-
+   
 ThirdChild: =>
 ThirdChild extends SecondChild
 ThirdChild.prototype.func: string =>