adds tests for varnish integration

manifests/integrations/varnish.pp

@@ -22,6 +22,7 @@
   $varnishstat = '/usr/bin/varnishstat',
   $tags      = [],
 ) inherits datadog_agent::params {
+  include datadog_agent
 
   file { "${datadog_agent::params::conf_dir}/varnish.yaml":
     ensure  => file,

spec/classes/datadog_agent_integrations_varnish_spec.rb

@@ -0,0 +1,38 @@
+require 'spec_helper'
+
+describe 'datadog_agent::integrations::varnish' do
+  let(:facts) {{
+    operatingsystem: 'Ubuntu',
+  }}
+  let(:conf_dir) { '/etc/dd-agent/conf.d' }
+  let(:dd_user) { 'dd-agent' }
+  let(:dd_group) { 'root' }
+  let(:dd_package) { 'datadog-agent' }
+  let(:dd_service) { 'datadog-agent' }
+  let(:conf_file) { "#{conf_dir}/varnish.yaml" }
+
+  it { should compile.with_all_deps }
+  it { should contain_file(conf_file).with(
+    owner: dd_user,
+    group: dd_group,
+    mode: '0600',
+  )}
+  it { should contain_file(conf_file).that_requires("Package[#{dd_package}]") }
+  it { should contain_file(conf_file).that_notifies("Service[#{dd_service}]") }
+
+
+  context 'with default parameters' do
+    it { should contain_file(conf_file).with_content(%r{varnishstat: /usr/bin/varnishstat}) }
+    it { should contain_file(conf_file).without_content(%r{tags: }) }
+  end
+
+  context 'with parameters set' do
+    let(:params){{
+      varnishstat: '/opt/bin/varnishstat',
+      tags: %w{ foo bar baz },
+    }}
+
+    it { should contain_file(conf_file).with_content(%r{varnishstat: /opt/bin/varnishstat}) }
+    it { should contain_file(conf_file).with_content(%r{tags:\s+- foo\s+- bar\s+- baz}) }
+  end
+end