We now check for powershell/dsc compat in provider.jdmundrawala/issue-2027-master

The problem with raising an exception when the resource is created
was that it was not possible to have a chef recipe that installs
the correct version of powershell and then runs the dsc_script
resource.
See https://github.com/opscode/chef/issues/2027

2 files changed, 33 insertions, 19 deletions

diff --git a/lib/chef/provider/dsc_script.rb b/lib/chef/provider/dsc_script.rb
index 5d7322842c..9bb2b5f364 100644
--- a/lib/chef/provider/dsc_script.rb
+++ b/lib/chef/provider/dsc_script.rb
@@ -46,9 +46,11 @@ class Chef
       end
 
       def load_current_resource
-        @dsc_resources_info = run_configuration(:test)
-        @resource_converged = @dsc_resources_info.all? do |resource|
-          !resource.changes_state?
+        if supports_dsc?
+          @dsc_resources_info = run_configuration(:test)
+          @resource_converged = @dsc_resources_info.all? do |resource|
+            !resource.changes_state?
+          end
         end
       end
 
@@ -56,8 +58,26 @@ class Chef
         true
       end
 
+      def define_resource_requirements
+        requirements.assert(:run) do |a|
+          err = [
+            'Could not find Dsc on the system',
+            powershell_info_str,
+            "Powershell 4.0 or higher was not detected on your system and is required to use the dsc_script resource.",
+          ]
+          a.assertion { supports_dsc? }
+          a.failure_message Chef::Exceptions::NoProviderAvailable, err.join(' ')
+          a.whyrun err + ["Assuming a previous resource installs Powershell 4.0 or higher."]
+          a.block_action!
+        end
+      end
+
       protected
 
+      def supports_dsc?
+        run_context && Chef::Platform.supports_dsc?(node)
+      end
+
       def run_configuration(operation)
         config_directory = ::Dir.mktmpdir("chef-dsc-script")
         configuration_data_path = get_configuration_data_path(config_directory)
@@ -143,6 +163,14 @@ class Chef
             end
           end
       end
+
+      def powershell_info_str
+        if run_context && run_context.node[:languages] && run_context.node[:languages][:powershell]
+          install_info = "Powershell #{run_context.node[:languages][:powershell][:version]} was found on the system."
+        else
+          install_info = 'Powershell was not found.'
+        end
+      end
     end
   end
 end
diff --git a/lib/chef/resource/dsc_script.rb b/lib/chef/resource/dsc_script.rb
index 2972ace1aa..76ac6659d6 100644
--- a/lib/chef/resource/dsc_script.rb
+++ b/lib/chef/resource/dsc_script.rb
@@ -28,12 +28,8 @@ class Chef
         super
         @allowed_actions.push(:run)
         @action = :run
-        if(run_context && Chef::Platform.supports_dsc?(run_context.node))
-          @provider = Chef::Provider::DscScript
-        else
-          raise Chef::Exceptions::NoProviderAvailable,
-            "#{powershell_info_str(run_context)}\nPowershell 4.0 or higher was not detected on your system and is required to use the dsc_script resource."
-        end
+        @provider = Chef::Provider::DscScript
+        @resource_name = :dsc_script
       end
 
       def code(arg=nil)
@@ -125,16 +121,6 @@ class Chef
           :kind_of => [ Integer ]
         )
       end
-
-      private
-
-      def powershell_info_str(run_context)
-        if run_context && run_context.node[:languages] && run_context.node[:languages][:powershell]
-            install_info = "Powershell #{run_context.node[:languages][:powershell][:version]} was found on the system."
-          else
-            install_info = 'Powershell was not found.'
-          end
-      end
     end
   end
 end