1 files changed, 26 insertions, 0 deletions
diff --git a/lib/chef/provider_resolver.rb b/lib/chef/provider_resolver.rb
index 465f88606b..439a7e9f5f 100644
--- a/lib/chef/provider_resolver.rb
+++ b/lib/chef/provider_resolver.rb
@@ -137,5 +137,31 @@ class Chef
     def overrode_provides?(handler)
       handler.method(:provides?).owner != Chef::Provider.method(:provides?).owner
     end
+
+    module Deprecated
+      # return a deterministically sorted list of Chef::Provider subclasses
+      def providers
+        @providers ||= Chef::Provider.descendants
+      end
+
+      def enabled_handlers
+        @enabled_handlers ||= begin
+          handlers = super
+          if handlers.empty?
+            # Look through all providers, and find ones that return true to provides.
+            # Don't bother with ones that don't override provides?, since they
+            # would have been in enabled_handlers already if that were so. (It's a
+            # perf concern otherwise.)
+            handlers = providers.select { |handler| overrode_provides?(handler) && handler.provides?(node, resource) }
+            handlers.each do |handler|
+              message = "#{handler}.provides? returned true when asked if it provides DSL #{resource.resource_name}, but provides #{resource.resource_name.inspect} was never called!  In Chef 13, this will break: you must call provides to mark the names you provide, even if you also override provides? yourself."
+              Chef.deprecated(:custom_resource, message)
+            end
+          end
+          handlers
+        end
+      end
+    end
+    prepend Deprecated
   end
 end