add suffix() to go along with prefix()

README.markdown

@@ -479,7 +479,7 @@ prefix
 ------
 This function applies a prefix to all elements in an array.
 
-*Examles:*
+*Examples:*
 
     prefix(['a','b','c'], 'p')
 
@@ -659,6 +659,19 @@ every string inside an array.
 Would result in: "aaa"
 
 
+- *Type*: rvalue
+
+suffix
+------
+This function applies a suffix to all elements in an array.
+
+*Examples:*
+
+    suffix(['a','b','c'], 'p')
+
+Will return: ['ap','bp','cp']
+
+
 - *Type*: rvalue
 
 swapcase

lib/puppet/parser/functions/prefix.rb

@@ -6,7 +6,7 @@ module Puppet::Parser::Functions
   newfunction(:prefix, :type => :rvalue, :doc => <<-EOS
 This function applies a prefix to all elements in an array.
 
-*Examles:*
+*Examples:*
 
     prefix(['a','b','c'], 'p')
 

lib/puppet/parser/functions/suffix.rb

@@ -0,0 +1,45 @@
+#
+# suffix.rb
+#
+
+module Puppet::Parser::Functions
+  newfunction(:suffix, :type => :rvalue, :doc => <<-EOS
+This function applies a suffix to all elements in an array.
+
+*Examples:*
+
+    suffix(['a','b','c'], 'p')
+
+Will return: ['ap','bp','cp']
+    EOS
+  ) do |arguments|
+
+    # Technically we support two arguments but only first is mandatory ...
+    raise(Puppet::ParseError, "suffix(): Wrong number of arguments " +
+      "given (#{arguments.size} for 1)") if arguments.size < 1
+
+    array = arguments[0]
+
+    unless array.is_a?(Array)
+      raise(Puppet::ParseError, 'suffix(): Requires array to work with')
+    end
+
+    suffix = arguments[1] if arguments[1]
+
+    if suffix
+      unless suffix.is_a?(String)
+        raise(Puppet::ParseError, 'suffix(): Requires string to work with')
+      end
+    end
+
+    # Turn everything into string same as join would do ...
+    result = array.collect do |i|
+      i = i.to_s
+      suffix ? i + suffix : i
+    end
+
+    return result
+  end
+end
+
+# vim: set ts=2 sw=2 et :

spec/unit/puppet/parser/functions/suffix_spec.rb

@@ -0,0 +1,19 @@
+#! /usr/bin/env ruby -S rspec
+require 'spec_helper'
+
+describe "the suffix function" do
+  let(:scope) { PuppetlabsSpec::PuppetInternals.scope }
+
+  it "should exist" do
+    Puppet::Parser::Functions.function("suffix").should == "function_suffix"
+  end
+
+  it "should raise a ParseError if there is less than 1 arguments" do
+    lambda { scope.function_suffix([]) }.should( raise_error(Puppet::ParseError))
+  end
+
+  it "should return a suffixed array" do
+    result = scope.function_suffix([['a','b','c'], 'p'])
+    result.should(eq(['ap','bp','cp']))
+  end
+end