Merge remote-tracking branch 'upstream/master'

26 files changed, 570 insertions, 36 deletions

diff --git a/lib/puppet/parser/functions/any2array.rb b/lib/puppet/parser/functions/any2array.rb
new file mode 100644
index 0000000..e71407e
--- /dev/null
+++ b/lib/puppet/parser/functions/any2array.rb
@@ -0,0 +1,33 @@
+#
+# any2array.rb
+#
+
+module Puppet::Parser::Functions
+  newfunction(:any2array, :type => :rvalue, :doc => <<-EOS
+This converts any object to an array containing that object. Empty argument
+lists are converted to an empty array. Arrays are left untouched. Hashes are
+converted to arrays of alternating keys and values.
+    EOS
+  ) do |arguments|
+
+    if arguments.empty?
+        return []
+    end
+
+    if arguments.length == 1
+        if arguments[0].kind_of?(Array)
+            return arguments[0]
+        elsif arguments[0].kind_of?(Hash)
+            result = []
+            arguments[0].each do |key, value|
+                result << key << value
+            end
+            return result
+        end
+    end
+
+    return arguments
+  end
+end
+
+# vim: set ts=2 sw=2 et :
diff --git a/lib/puppet/parser/functions/base64.rb b/lib/puppet/parser/functions/base64.rb
new file mode 100644
index 0000000..d9a590a
--- /dev/null
+++ b/lib/puppet/parser/functions/base64.rb
@@ -0,0 +1,37 @@
+module Puppet::Parser::Functions
+ 
+  newfunction(:base64, :type => :rvalue, :doc => <<-'ENDHEREDOC') do |args|
+
+    Base64 encode or decode a string based on the command and the string submitted
+
+    Usage:
+
+      $encodestring = base64('encode','thestring')
+      $decodestring = base64('decode','dGhlc3RyaW5n')
+
+    ENDHEREDOC
+ 
+    require 'base64'
+ 
+    raise Puppet::ParseError, ("base64(): Wrong number of arguments (#{args.length}; must be = 2)") unless args.length == 2
+
+    actions = ['encode','decode']
+
+    unless actions.include?(args[0])
+      raise Puppet::ParseError, ("base64(): the first argument must be one of 'encode' or 'decode'")
+    end
+ 
+    unless args[1].is_a?(String)
+      raise Puppet::ParseError, ("base64(): the second argument must be a string to base64")
+    end
+ 
+    case args[0]
+      when 'encode'
+        result = Base64.encode64(args[1])
+      when 'decode'
+        result = Base64.decode64(args[1])
+    end
+ 
+    return result
+  end
+end
diff --git a/lib/puppet/parser/functions/concat.rb b/lib/puppet/parser/functions/concat.rb
new file mode 100644
index 0000000..c86aa00
--- /dev/null
+++ b/lib/puppet/parser/functions/concat.rb
@@ -0,0 +1,37 @@
+#
+# 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 both args are arrays.
+    unless a.is_a?(Array) and b.is_a?(Array)
+      raise(Puppet::ParseError, 'concat(): Requires array to work with')
+    end
+
+    result = a.concat(b)
+
+    return result
+  end
+end
+
+# vim: set ts=2 sw=2 et :
diff --git a/lib/puppet/parser/functions/count.rb b/lib/puppet/parser/functions/count.rb
new file mode 100644
index 0000000..52de1b8
--- /dev/null
+++ b/lib/puppet/parser/functions/count.rb
@@ -0,0 +1,22 @@
+module Puppet::Parser::Functions
+  newfunction(:count, :type => :rvalue, :arity => -2, :doc => <<-EOS
+Takes an array as first argument and an optional second argument.
+Count the number of elements in array that matches second argument.
+If called with only an array it counts the number of elements that are not nil/undef.
+    EOS
+  ) do |args|
+
+    if (args.size > 2) then
+      raise(ArgumentError, "count(): Wrong number of arguments "+
+        "given #{args.size} for 1 or 2.")
+    end
+
+    collection, item = args
+
+    if item then
+      collection.count item
+    else
+      collection.count { |obj| obj != nil && obj != :undef && obj != '' }
+    end
+  end
+end
diff --git a/lib/puppet/parser/functions/difference.rb b/lib/puppet/parser/functions/difference.rb
new file mode 100644
index 0000000..cd258f7
--- /dev/null
+++ b/lib/puppet/parser/functions/difference.rb
@@ -0,0 +1,36 @@
+#
+# difference.rb
+#
+
+module Puppet::Parser::Functions
+  newfunction(:difference, :type => :rvalue, :doc => <<-EOS
+This function returns the difference between two arrays.
+The returned array is a copy of the original array, removing any items that
+also appear in the second array.
+
+*Examples:*
+
+    difference(["a","b","c"],["b","c","d"])
+
+Would return: ["a"]
+    EOS
+  ) do |arguments|
+
+    # Two arguments are required
+    raise(Puppet::ParseError, "difference(): Wrong number of arguments " +
+      "given (#{arguments.size} for 2)") if arguments.size != 2
+
+    first = arguments[0]
+    second = arguments[1]
+
+    unless first.is_a?(Array) && second.is_a?(Array)
+      raise(Puppet::ParseError, 'difference(): Requires 2 arrays')
+    end
+
+    result = first - second
+
+    return result
+  end
+end
+
+# vim: set ts=2 sw=2 et :
diff --git a/lib/puppet/parser/functions/dirname.rb b/lib/puppet/parser/functions/dirname.rb
new file mode 100644
index 0000000..ea8cc1e
--- /dev/null
+++ b/lib/puppet/parser/functions/dirname.rb
@@ -0,0 +1,15 @@
+module Puppet::Parser::Functions
+  newfunction(:dirname, :type => :rvalue, :doc => <<-EOS
+    Returns the dirname of a path.
+    EOS
+  ) do |arguments|
+
+    raise(Puppet::ParseError, "dirname(): Wrong number of arguments " +
+      "given (#{arguments.size} for 1)") if arguments.size < 1
+
+    path = arguments[0]
+    return File.dirname(path)
+  end
+end
+
+# vim: set ts=2 sw=2 et :
diff --git a/lib/puppet/parser/functions/ensure_resource.rb b/lib/puppet/parser/functions/ensure_resource.rb
index fba2035..a9a1733 100644
--- a/lib/puppet/parser/functions/ensure_resource.rb
+++ b/lib/puppet/parser/functions/ensure_resource.rb
@@ -19,17 +19,27 @@ If the resource already exists but does not match the specified parameters,
 this function will attempt to recreate the resource leading to a duplicate
 resource definition error.
 
+An array of resources can also be passed in and each will be created with
+the type and parameters specified if it doesn't already exist.
+
+    ensure_resource('user', ['dan','alex'], {'ensure' => 'present'})
+
 ENDOFDOC
 ) do |vals|
   type, title, params = vals
   raise(ArgumentError, 'Must specify a type') unless type
   raise(ArgumentError, 'Must specify a title') unless title
   params ||= {}
-  Puppet::Parser::Functions.function(:defined_with_params)
-  if function_defined_with_params(["#{type}[#{title}]", params])
-    Puppet.debug("Resource #{type}[#{title}] not created b/c it already exists")
-  else
-    Puppet::Parser::Functions.function(:create_resources)
-    function_create_resources([type.capitalize, { title => params }])
+
+  items = [title].flatten
+
+  items.each do |item|
+    Puppet::Parser::Functions.function(:defined_with_params)
+    if function_defined_with_params(["#{type}[#{item}]", params])
+      Puppet.debug("Resource #{type}[#{item}] not created because it already exists")
+    else
+      Puppet::Parser::Functions.function(:create_resources)
+      function_create_resources([type.capitalize, { item => params }])
+    end
   end
 end
diff --git a/lib/puppet/parser/functions/flatten.rb b/lib/puppet/parser/functions/flatten.rb
index 781da78..a1ed183 100644
--- a/lib/puppet/parser/functions/flatten.rb
+++ b/lib/puppet/parser/functions/flatten.rb
@@ -16,7 +16,7 @@ Would return: ['a','b','c']
   ) do |arguments|
 
     raise(Puppet::ParseError, "flatten(): Wrong number of arguments " +
-      "given (#{arguments.size} for 1)") if arguments.size < 1
+      "given (#{arguments.size} for 1)") if arguments.size != 1
 
     array = arguments[0]
 
diff --git a/lib/puppet/parser/functions/floor.rb b/lib/puppet/parser/functions/floor.rb
new file mode 100644
index 0000000..a401923
--- /dev/null
+++ b/lib/puppet/parser/functions/floor.rb
@@ -0,0 +1,20 @@
+module Puppet::Parser::Functions
+  newfunction(:floor, :type => :rvalue, :doc => <<-EOS
+    Returns the largest integer less or equal to the argument.
+    Takes a single numeric value as an argument.
+    EOS
+  ) do |arguments|
+
+    raise(Puppet::ParseError, "floor(): Wrong number of arguments " +
+          "given (#{arguments.size} for 1)") if arguments.size != 1
+
+    arg = arguments[0]
+
+    raise(Puppet::ParseError, "floor(): Wrong argument type " +
+          "given (#{arg.class} for Numeric)") if arg.is_a?(Numeric) == false
+
+    arg.floor
+  end
+end
+
+# vim: set ts=2 sw=2 et :
diff --git a/lib/puppet/parser/functions/getparam.rb b/lib/puppet/parser/functions/getparam.rb
new file mode 100644
index 0000000..6d51006
--- /dev/null
+++ b/lib/puppet/parser/functions/getparam.rb
@@ -0,0 +1,35 @@
+# Test whether a given class or definition is defined
+require 'puppet/parser/functions'
+
+Puppet::Parser::Functions.newfunction(:getparam,
+                                      :type => :rvalue,
+                                      :doc => <<-'ENDOFDOC'
+Takes a resource reference and name of the parameter and
+returns value of resource's parameter.
+
+*Examples:*
+
+    define example_resource($param) {
+    }
+
+    example_resource { "example_resource_instance":
+        param => "param_value"
+    }
+
+    getparam(Example_resource["example_resource_instance"], "param")
+
+Would return: param_value
+ENDOFDOC
+) do |vals|
+  reference, param = vals
+  raise(ArgumentError, 'Must specify a reference') unless reference
+  raise(ArgumentError, 'Must specify name of a parameter') unless param and param.instance_of? String
+
+  return '' if param.empty?
+
+  if resource = findresource(reference.to_s)
+    return resource[param] if resource[param]
+  end
+
+  return ''
+end
diff --git a/lib/puppet/parser/functions/hash.rb b/lib/puppet/parser/functions/hash.rb
index 453ba1e..8cc4823 100644
--- a/lib/puppet/parser/functions/hash.rb
+++ b/lib/puppet/parser/functions/hash.rb
@@ -4,7 +4,7 @@
 
 module Puppet::Parser::Functions
   newfunction(:hash, :type => :rvalue, :doc => <<-EOS
-This function converts and array into a hash.
+This function converts an array into a hash.
 
 *Examples:*
 
diff --git a/lib/puppet/parser/functions/intersection.rb b/lib/puppet/parser/functions/intersection.rb
new file mode 100644
index 0000000..48f02e9
--- /dev/null
+++ b/lib/puppet/parser/functions/intersection.rb
@@ -0,0 +1,34 @@
+#
+# intersection.rb
+#
+
+module Puppet::Parser::Functions
+  newfunction(:intersection, :type => :rvalue, :doc => <<-EOS
+This function returns an array an intersection of two.
+
+*Examples:*
+
+    intersection(["a","b","c"],["b","c","d"])
+
+Would return: ["b","c"]
+    EOS
+  ) do |arguments|
+
+    # Two arguments are required
+    raise(Puppet::ParseError, "intersection(): Wrong number of arguments " +
+      "given (#{arguments.size} for 2)") if arguments.size != 2
+
+    first = arguments[0]
+    second = arguments[1]
+
+    unless first.is_a?(Array) && second.is_a?(Array)
+      raise(Puppet::ParseError, 'intersection(): Requires 2 arrays')
+    end
+
+    result = first & second
+
+    return result
+  end
+end
+
+# vim: set ts=2 sw=2 et :
diff --git a/lib/puppet/parser/functions/is_float.rb b/lib/puppet/parser/functions/is_float.rb
index 2fc05ba..911f3c2 100644
--- a/lib/puppet/parser/functions/is_float.rb
+++ b/lib/puppet/parser/functions/is_float.rb
@@ -15,7 +15,7 @@ Returns true if the variable passed to this function is a float.
 
     value = arguments[0]
 
-    if value != value.to_f.to_s then
+    if value != value.to_f.to_s and !value.is_a? Float then
       return false
     else
       return true
diff --git a/lib/puppet/parser/functions/is_function_available.rb b/lib/puppet/parser/functions/is_function_available.rb
new file mode 100644
index 0000000..6cbd35c
--- /dev/null
+++ b/lib/puppet/parser/functions/is_function_available.rb
@@ -0,0 +1,23 @@
+#
+# is_function_available.rb
+#
+
+module Puppet::Parser::Functions
+  newfunction(:is_function_available, :type => :rvalue, :doc => <<-EOS
+This function accepts a string as an argument, determines whether the
+Puppet runtime has access to a function by that name.  It returns a
+true if the function exists, false if not.
+    EOS
+  ) do |arguments|
+
+    if (arguments.size != 1) then
+      raise(Puppet::ParseError, "is_function_available?(): Wrong number of arguments "+
+        "given #{arguments.size} for 1")
+    end
+
+    function = Puppet::Parser::Functions.function(arguments[0].to_sym)
+    function.is_a?(String) and not function.empty?
+  end
+end
+
+# vim: set ts=2 sw=2 et :
diff --git a/lib/puppet/parser/functions/is_integer.rb b/lib/puppet/parser/functions/is_integer.rb
index 8ee34f6..6b29e98 100644
--- a/lib/puppet/parser/functions/is_integer.rb
+++ b/lib/puppet/parser/functions/is_integer.rb
@@ -15,7 +15,7 @@ Returns true if the variable returned to this string is an integer.
 
     value = arguments[0]
 
-    if value != value.to_i.to_s then
+    if value != value.to_i.to_s and !value.is_a? Fixnum then
       return false
     else
       return true
diff --git a/lib/puppet/parser/functions/is_numeric.rb b/lib/puppet/parser/functions/is_numeric.rb
index ce13ece..abf0321 100644
--- a/lib/puppet/parser/functions/is_numeric.rb
+++ b/lib/puppet/parser/functions/is_numeric.rb
@@ -15,7 +15,7 @@ Returns true if the variable passed to this function is a number.
 
     value = arguments[0]
 
-    if value == value.to_f.to_s or value == value.to_i.to_s then
+    if value == value.to_f.to_s or value == value.to_i.to_s or value.is_a? Numeric then
       return true
     else
       return false
diff --git a/lib/puppet/parser/functions/max.rb b/lib/puppet/parser/functions/max.rb
index 10b6f74..60fb94a 100644
--- a/lib/puppet/parser/functions/max.rb
+++ b/lib/puppet/parser/functions/max.rb
@@ -8,6 +8,14 @@ module Puppet::Parser::Functions
     raise(Puppet::ParseError, "max(): Wrong number of arguments " +
           "need at least one") if args.size == 0
 
-    return args.max
+    # Sometimes we get numbers as numerics and sometimes as strings.
+    # We try to compare them as numbers when possible
+    return args.max do |a,b|
+      if a.to_s =~ /\A-?\d+(.\d+)?\z/ and b.to_s =~ /\A-?\d+(.\d+)?\z/ then
+        a.to_f <=> b.to_f
+      else
+        a.to_s <=> b.to_s
+      end
+    end
   end
 end
diff --git a/lib/puppet/parser/functions/merge.rb b/lib/puppet/parser/functions/merge.rb
index 6ec085e..1b39f20 100644
--- a/lib/puppet/parser/functions/merge.rb
+++ b/lib/puppet/parser/functions/merge.rb
@@ -22,6 +22,7 @@ module Puppet::Parser::Functions
     accumulator = Hash.new
     # Merge into the accumulator hash
     args.each do |arg|
+      next if arg.is_a? String and arg.empty? # empty string is synonym for puppet's undef
       unless arg.is_a?(Hash)
         raise Puppet::ParseError, "merge: unexpected argument type #{arg.class}, only expects hash arguments"
       end
diff --git a/lib/puppet/parser/functions/min.rb b/lib/puppet/parser/functions/min.rb
index abf1b62..6bd6ebf 100644
--- a/lib/puppet/parser/functions/min.rb
+++ b/lib/puppet/parser/functions/min.rb
@@ -8,6 +8,14 @@ module Puppet::Parser::Functions
     raise(Puppet::ParseError, "min(): Wrong number of arguments " +
           "need at least one") if args.size == 0
 
-    return args.min
+    # Sometimes we get numbers as numerics and sometimes as strings.
+    # We try to compare them as numbers when possible
+    return args.min do |a,b|
+      if a.to_s =~ /\A^-?\d+(.\d+)?\z/ and b.to_s =~ /\A-?\d+(.\d+)?\z/ then
+        a.to_f <=> b.to_f
+      else
+        a.to_s <=> b.to_s
+      end
+    end
   end
 end
diff --git a/lib/puppet/parser/functions/num2bool.rb b/lib/puppet/parser/functions/num2bool.rb
index 874db22..af0e6ed 100644
--- a/lib/puppet/parser/functions/num2bool.rb
+++ b/lib/puppet/parser/functions/num2bool.rb
@@ -2,38 +2,41 @@
 # num2bool.rb
 #
 
-# TODO(Krzysztof Wilczynski): We probably need to approach numeric values differently ...
-
 module Puppet::Parser::Functions
   newfunction(:num2bool, :type => :rvalue, :doc => <<-EOS
-This function converts a number into a true boolean. Zero becomes false. Numbers
-higher then 0 become true.
+This function converts a number or a string representation of a number into a
+true boolean. Zero or anything non-numeric becomes false. Numbers higher then 0
+become true.
     EOS
   ) do |arguments|
 
     raise(Puppet::ParseError, "num2bool(): Wrong number of arguments " +
-      "given (#{arguments.size} for 1)") if arguments.size < 1
+      "given (#{arguments.size} for 1)") if arguments.size != 1
 
     number = arguments[0]
 
-    # Only numbers allowed ...
-    unless number.match(/^\-?\d+$/)
-      raise(Puppet::ParseError, 'num2bool(): Requires integer to work with')
+    case number
+    when Numeric
+      # Yay, it's a number
+    when String
+      begin
+        number = Float(number)
+      rescue ArgumentError => ex
+        raise(Puppet::ParseError, "num2bool(): '#{number}' does not look like a number: #{ex.message}")
+      end
+    else
+      begin
+        number = number.to_s
+      rescue NoMethodError => ex
+        raise(Puppet::ParseError, "num2bool(): Unable to parse argument: #{ex.message}")
+      end
     end
 
-    result = case number
-      when /^0$/
-        false
-      when /^\-?\d+$/
-        # Numbers in Puppet are often string-encoded which is troublesome ...
-        number = number.to_i
-        # We yield true for any positive number and false otherwise ...
-        number > 0 ? true : false
-      else
-        raise(Puppet::ParseError, 'num2bool(): Unknown numeric format given')
-    end
+    # Truncate Floats
+    number = number.to_i
 
-    return result
+    # Return true for any positive number and false otherwise
+    return number > 0
   end
 end
 
diff --git a/lib/puppet/parser/functions/prefix.rb b/lib/puppet/parser/functions/prefix.rb
index 4593976..62211ae 100644
--- a/lib/puppet/parser/functions/prefix.rb
+++ b/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')
 
@@ -21,14 +21,14 @@ Will return: ['pa','pb','pc']
     array = arguments[0]
 
     unless array.is_a?(Array)
-      raise(Puppet::ParseError, 'prefix(): Requires array to work with')
+      raise Puppet::ParseError, "prefix(): expected first argument to be an Array, got #{array.inspect}"
     end
 
     prefix = arguments[1] if arguments[1]
 
     if prefix
       unless prefix.is_a?(String)
-        raise(Puppet::ParseError, 'prefix(): Requires string to work with')
+        raise Puppet::ParseError, "prefix(): expected second argument to be a String, got #{suffix.inspect}"
       end
     end
 
diff --git a/lib/puppet/parser/functions/str2bool.rb b/lib/puppet/parser/functions/str2bool.rb
index 0509c2b..fece7a6 100644
--- a/lib/puppet/parser/functions/str2bool.rb
+++ b/lib/puppet/parser/functions/str2bool.rb
@@ -14,6 +14,11 @@ like: 0, f, n, false, no to 'false'.
       "given (#{arguments.size} for 1)") if arguments.size < 1
 
     string = arguments[0]
+    
+    # If string is already Boolean, return it
+    if !!string == string
+      return string
+    end
 
     unless string.is_a?(String)
       raise(Puppet::ParseError, 'str2bool(): Requires either ' +
diff --git a/lib/puppet/parser/functions/suffix.rb b/lib/puppet/parser/functions/suffix.rb
new file mode 100644
index 0000000..f7792d6
--- /dev/null
+++ b/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(): expected first argument to be an Array, got #{array.inspect}"
+    end
+
+    suffix = arguments[1] if arguments[1]
+
+    if suffix
+      unless suffix.is_a? String
+        raise Puppet::ParseError, "suffix(): expected second argument to be a String, got #{suffix.inspect}"
+      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 :
diff --git a/lib/puppet/parser/functions/union.rb b/lib/puppet/parser/functions/union.rb
new file mode 100644
index 0000000..c91bb80
--- /dev/null
+++ b/lib/puppet/parser/functions/union.rb
@@ -0,0 +1,34 @@
+#
+# union.rb
+#
+
+module Puppet::Parser::Functions
+  newfunction(:union, :type => :rvalue, :doc => <<-EOS
+This function returns a union of two arrays.
+
+*Examples:*
+
+    union(["a","b","c"],["b","c","d"])
+
+Would return: ["a","b","c","d"]
+    EOS
+  ) do |arguments|
+
+    # Two arguments are required
+    raise(Puppet::ParseError, "union(): Wrong number of arguments " +
+      "given (#{arguments.size} for 2)") if arguments.size != 2
+
+    first = arguments[0]
+    second = arguments[1]
+
+    unless first.is_a?(Array) && second.is_a?(Array)
+      raise(Puppet::ParseError, 'union(): Requires 2 arrays')
+    end
+
+    result = first | second
+
+    return result
+  end
+end
+
+# vim: set ts=2 sw=2 et :
diff --git a/lib/puppet/parser/functions/validate_augeas.rb b/lib/puppet/parser/functions/validate_augeas.rb
new file mode 100644
index 0000000..154d660
--- /dev/null
+++ b/lib/puppet/parser/functions/validate_augeas.rb
@@ -0,0 +1,81 @@
+module Puppet::Parser::Functions
+  newfunction(:validate_augeas, :doc => <<-'ENDHEREDOC') do |args|
+    Perform validation of a string using an Augeas lens
+    The first argument of this function should be a string to
+    test, and the second argument should be the name of the Augeas lens to use.
+    If Augeas fails to parse the string with the lens, the compilation will
+    abort with a parse error.
+
+    A third argument can be specified, listing paths which should
+    not be found in the file. The `$file` variable points to the location
+    of the temporary file being tested in the Augeas tree.
+
+    For example, if you want to make sure your passwd content never contains
+    a user `foo`, you could write:
+
+        validate_augeas($passwdcontent, 'Passwd.lns', ['$file/foo'])
+
+    Or if you wanted to ensure that no users used the '/bin/barsh' shell,
+    you could use:
+
+        validate_augeas($passwdcontent, 'Passwd.lns', ['$file/*[shell="/bin/barsh"]']
+
+    If a fourth argument is specified, this will be the error message raised and
+    seen by the user.
+
+    A helpful error message can be returned like this:
+
+        validate_augeas($sudoerscontent, 'Sudoers.lns', [], 'Failed to validate sudoers content with Augeas')
+
+    ENDHEREDOC
+    unless Puppet.features.augeas?
+      raise Puppet::ParseError, ("validate_augeas(): this function requires the augeas feature. See http://projects.puppetlabs.com/projects/puppet/wiki/Puppet_Augeas#Pre-requisites for how to activate it.")
+    end
+
+    if (args.length < 2) or (args.length > 4) then
+      raise Puppet::ParseError, ("validate_augeas(): wrong number of arguments (#{args.length}; must be 2, 3, or 4)")
+    end
+
+    msg = args[3] || "validate_augeas(): Failed to validate content against #{args[1].inspect}"
+
+    require 'augeas'
+    aug = Augeas::open(nil, nil, Augeas::NO_MODL_AUTOLOAD)
+    begin
+      content = args[0]
+
+      # Test content in a temporary file
+      tmpfile = Tempfile.new("validate_augeas")
+      begin
+        tmpfile.write(content)
+      ensure
+        tmpfile.close
+      end
+
+      # Check for syntax
+      lens = args[1]
+      aug.transform(
+        :lens => lens,
+        :name => 'Validate_augeas',
+        :incl => tmpfile.path
+      )
+      aug.load!
+
+      unless aug.match("/augeas/files#{tmpfile.path}//error").empty?
+        error = aug.get("/augeas/files#{tmpfile.path}//error/message")
+        msg += " with error: #{error}"
+        raise Puppet::ParseError, (msg)
+      end
+
+      # Launch unit tests
+      tests = args[2] || []
+      aug.defvar('file', "/files#{tmpfile.path}")
+      tests.each do |t|
+        msg += " testing path #{t}"
+        raise Puppet::ParseError, (msg) unless aug.match(t).empty?
+      end
+    ensure
+      aug.close
+      tmpfile.unlink
+    end
+  end
+end
diff --git a/lib/puppet/parser/functions/validate_cmd.rb b/lib/puppet/parser/functions/validate_cmd.rb
new file mode 100644
index 0000000..344a80c
--- /dev/null
+++ b/lib/puppet/parser/functions/validate_cmd.rb
@@ -0,0 +1,47 @@
+require 'puppet/util/execution'
+
+module Puppet::Parser::Functions
+  newfunction(:validate_cmd, :doc => <<-'ENDHEREDOC') do |args|
+    Perform validation of a string with an external command.
+    The first argument of this function should be a string to
+    test, and the second argument should be a path to a test command
+    taking a file as last argument. If the command, launched against
+    a tempfile containing the passed string, returns a non-null value,
+    compilation will abort with a parse error.
+
+    If a third argument is specified, this will be the error message raised and
+    seen by the user.
+
+    A helpful error message can be returned like this:
+
+    Example:
+
+        validate_cmd($sudoerscontent, '/usr/sbin/visudo -c -f', 'Visudo failed to validate sudoers content')
+
+    ENDHEREDOC
+    if (args.length < 2) or (args.length > 3) then
+      raise Puppet::ParseError, ("validate_cmd(): wrong number of arguments (#{args.length}; must be 2 or 3)")
+    end
+
+    msg = args[2] || "validate_cmd(): failed to validate content with command #{args[1].inspect}"
+
+    content = args[0]
+    checkscript = args[1]
+
+    # Test content in a temporary file
+    tmpfile = Tempfile.new("validate_cmd")
+    begin
+      tmpfile.write(content)
+      if Puppet::Util::Execution.respond_to?('execute')
+        Puppet::Util::Execution.execute("#{checkscript} #{tmpfile.path}")
+      else
+        Puppet::Util.execute("#{checkscript} #{tmpfile.path}")
+      end
+    rescue Puppet::ExecutionFailure => detail
+      msg += "\n#{detail}"
+      raise Puppet::ParseError, msg
+    ensure
+      tmpfile.unlink
+    end
+  end
+end