6 files changed, 44 insertions, 15 deletions
diff --git a/lib/puppet/parser/functions/delete.rb b/lib/puppet/parser/functions/delete.rb
index f814344..d03a293 100644
--- a/lib/puppet/parser/functions/delete.rb
+++ b/lib/puppet/parser/functions/delete.rb
@@ -27,7 +27,7 @@ string, or key from a hash.
         "given #{arguments.size} for 2.")
     end
 
-    collection = arguments[0]
+    collection = arguments[0].dup
     item = arguments[1]
 
     case collection
diff --git a/lib/puppet/parser/functions/delete_undef_values.rb b/lib/puppet/parser/functions/delete_undef_values.rb
index 4eecab2..532639e 100644
--- a/lib/puppet/parser/functions/delete_undef_values.rb
+++ b/lib/puppet/parser/functions/delete_undef_values.rb
@@ -18,16 +18,16 @@ Would return: ['A','',false]
     raise(Puppet::ParseError,
           "delete_undef_values(): Wrong number of arguments given " +
           "(#{args.size})") if args.size < 1
-
-    result = args[0]
+    
+    unless args[0].is_a? Array or args[0].is_a? Hash 
+      raise(Puppet::ParseError,
+            "delete_undef_values(): expected an array or hash, got #{args[0]} type  #{args[0].class} ")
+    end
+    result = args[0].dup 
     if result.is_a?(Hash)
       result.delete_if {|key, val| val.equal? :undef}
     elsif result.is_a?(Array)
       result.delete :undef
-    else
-      raise(Puppet::ParseError, 
-            "delete_undef_values(): Wrong argument type #{args[0].class} " +
-            "for first argument")
     end
     result
   end
diff --git a/lib/puppet/parser/functions/delete_values.rb b/lib/puppet/parser/functions/delete_values.rb
index 17b9d37..ca8eef5 100644
--- a/lib/puppet/parser/functions/delete_values.rb
+++ b/lib/puppet/parser/functions/delete_values.rb
@@ -21,6 +21,6 @@ Would return: {'a'=>'A','c'=>'C','B'=>'D'}
       raise(TypeError, "delete_values(): First argument must be a Hash. " + \
                        "Given an argument of class #{hash.class}.") 
     end
-    hash.delete_if { |key, val| item == val }
+    hash.dup.delete_if { |key, val| item == val }
   end
 end
diff --git a/lib/puppet/parser/functions/pick.rb b/lib/puppet/parser/functions/pick.rb
index cbc0300..e9e5d66 100644
--- a/lib/puppet/parser/functions/pick.rb
+++ b/lib/puppet/parser/functions/pick.rb
@@ -21,7 +21,7 @@ EOS
    args.delete(:undefined)
    args.delete("")
    if args[0].to_s.empty? then
-     fail "Must provide non empty value."
+     fail Puppet::ParseError, "pick(): must receive at last one non empty value"
    else
      return args[0]
    end
diff --git a/lib/puppet/provider/file_line/ruby.rb b/lib/puppet/provider/file_line/ruby.rb
index 3cb9f6e..94e7fac 100644
--- a/lib/puppet/provider/file_line/ruby.rb
+++ b/lib/puppet/provider/file_line/ruby.rb
@@ -1,5 +1,4 @@
 Puppet::Type.type(:file_line).provide(:ruby) do
-
   def exists?
     lines.find do |line|
       line.chomp == resource[:line].chomp
@@ -8,9 +7,11 @@ Puppet::Type.type(:file_line).provide(:ruby) do
 
   def create
     if resource[:match]
-      handle_create_with_match()
+      handle_create_with_match
+    elsif resource[:after]
+      handle_create_with_after
     else
-      handle_create_without_match()
+      append_line
     end
   end
 
@@ -48,11 +49,35 @@ Puppet::Type.type(:file_line).provide(:ruby) do
     end
   end
 
-  def handle_create_without_match
+  def handle_create_with_after
+    regex = Regexp.new(resource[:after])
+
+    count = lines.count {|l| l.match(regex)}
+
+    case count
+    when 1 # find the line to put our line after
+      File.open(resource[:path], 'w') do |fh|
+        lines.each do |l|
+          fh.puts(l)
+          if regex.match(l) then
+            fh.puts(resource[:line])
+          end
+        end
+      end
+    when 0 # append the line to the end of the file
+      append_line
+    else
+      raise Puppet::Error, "#{count} lines match pattern '#{resource[:after]}' in file '#{resource[:path]}'.  One or no line must match the pattern."
+    end
+  end
+
+  ##
+  # append the line to the file.
+  #
+  # @api private
+  def append_line
     File.open(resource[:path], 'a') do |fh|
       fh.puts resource[:line]
     end
   end
-
-
 end
diff --git a/lib/puppet/type/file_line.rb b/lib/puppet/type/file_line.rb
index 14946bb..323fc4c 100644
--- a/lib/puppet/type/file_line.rb
+++ b/lib/puppet/type/file_line.rb
@@ -42,6 +42,10 @@ Puppet::Type.newtype(:file_line) do
     newvalues(true, false)
   end
 
+  newparam(:after) do
+    desc 'An optional value used to specify the line after which we will add any new lines. (Existing lines are added in place)'
+  end
+
   newparam(:line) do
     desc 'The line to be appended to the file located by the path parameter.'
   end