Replace concat.rb with latest stdlib equivalent

Sync concat puppet function to fix some bugs

Related-Bug: #1320184
Related-Bug: #1321284

Change-Id: I49a614122469b37b1c4eb2fbc29b0877a4427fbd

deployment/puppet/common/lib/puppet/parser/functions/concat.rb

@@ -1,17 +0,0 @@
-# concat.rb
-
-# concatenate the contents of arrays
-# Use it like this:
-# $base_metrics = ['a', 'b']
-# $extended_metrics = ['c']
-# $metrics = concat($base_metrics, $extended_metrics)
-module Puppet::Parser::Functions
-	newfunction(:concat, :type => :rvalue) do |args|
-		result = []
-		args.each do |arg|
-			result = result.concat(arg)
-		end
-		result
-	end
-end
-

deployment/puppet/stdlib/lib/puppet/parser/functions/concat.rb

@@ -0,0 +1,41 @@
+#
+# concat.rb
+#
+
+module Puppet::Parser::Functions
+  newfunction(:concat, :type => :rvalue, :doc => <<-EOS
+Appends the contents of array 2 onto array 1.
+
+*Example:*
+
+    concat(['1','2','3'],['4','5','6'])
+
+Would result in:
+
+  ['1','2','3','4','5','6']
+    EOS
+  ) do |arguments|
+
+    # Check that 2 arguments have been given ...
+    raise(Puppet::ParseError, "concat(): Wrong number of arguments " +
+      "given (#{arguments.size} for 2)") if arguments.size != 2
+
+    a = arguments[0]
+    b = arguments[1]
+
+    # Check that the first parameter is an array
+    unless a.is_a?(Array)
+      raise(Puppet::ParseError, 'concat(): Requires array to work with')
+    end
+
+    if b.is_a?(Array)
+      result = a.concat(b)
+    else
+      result = a << b
+    end
+
+    return result
+  end
+end
+
+# vim: set ts=2 sw=2 et :