Add ensure_absent_val behavior to Nuage neutron plugin type

This change adds ensure_absent_val behavior to Nuage neutron plugin
type. This property ensure absent when the value is either specified
as <SERVICE DEFAULT> or ensure_absent_val.

Added spec tests for ensure_absent_val

Change-Id: Ifb9df534463a820ac5b2c3b965e01bc61833f8de

lib/puppet/type/neutron_plugin_nuage.rb

@@ -16,6 +16,11 @@ Puppet::Type.newtype(:neutron_plugin_nuage) do
     end
   end
 
+  newparam(:ensure_absent_val) do
+    desc 'A value that is specified as the value property will behave as if ensure => absent was specified'
+    defaultto('<SERVICE DEFAULT>')
+  end
+
   autorequire(:package) do
     'neutron-plugin-nuage'
   end

spec/unit/provider/neutron_plugin_nuage/ini_setting_spec.rb

@@ -33,5 +33,23 @@ describe provider_class do
       end
     end
   end
+
+  it 'should ensure absent when <SERVICE DEFAULT> is specified as a value' do
+    resource = Puppet::Type::Neutron_plugin_nuage.new(
+      {:name => 'somename/foo', :value => '<SERVICE DEFAULT>'}
+    )
+    provider = provider_class.new(resource)
+    provider.exists?
+    expect(resource[:ensure]).to eq :absent
+  end
+
+  it 'should ensure absent when value matches ensure_absent_val' do
+    resource = Puppet::Type::Neutron_plugin_nuage.new(
+      {:name => 'somename/foo', :value => 'foo', :ensure_absent_val => 'foo' }
+    )
+    provider = provider_class.new(resource)
+    provider.exists?
+    expect(resource[:ensure]).to eq :absent
+  end
 end