[WIP] don't change child nodes

lib/active_triples/relation.rb

@@ -285,11 +285,11 @@ def value_to_node(val)
       def add_child_node(resource, object = nil)
         parent.insert [rdf_subject, predicate, resource.rdf_subject]
 
+        resource = resource.dup
         unless resource.frozen? || 
                resource == parent || 
-               resource.persistence_strategy.is_a?(ParentStrategy) ||
                (parent.persistence_strategy.is_a?(ParentStrategy) &&
-                parent.persistence_strategy.ancestors.include?(resource))
+                parent.persistence_strategy.ancestors.find { |a| a.eql? resource })
           resource.set_persistence_strategy(ParentStrategy)
           resource.parent = parent
         end

spec/active_triples/rdf_source_spec.rb

@@ -500,18 +500,23 @@ class SourceWithCreator
     describe 'capturing child nodes' do
       let(:other) { source_class.new }
 
-      it 'captures a child node' do
+      it 'adds child node data to own graph' do
+        other << RDF::Statement(:s, RDF::URI('p'), 'o')
         expect { subject.set_value(RDF::OWL.sameAs, other) }
-          .to change { other.persistence_strategy }
-               .to(ActiveTriples::ParentStrategy)
-        expect(other.persistence_strategy.parent).to eq subject
+          .to change { subject.statements.to_a }.to include(*other.statements.to_a)
+      end
+
+      it 'does not change persistence strategy of added node' do
+        expect { subject.set_value(RDF::OWL.sameAs, other) }
+          .not_to change { other.persistence_strategy }
       end
 
       it 'does not capture a child node when it already persists to a parent' do
         third = source_class.new
         third.set_value(RDF::OWL.sameAs, other)
-
-        expect { subject.set_value(RDF::OWL.sameAs, other) }
+
+        child_other = third.get_values(RDF::OWL.sameAs).first
+        expect { subject.set_value(RDF::OWL.sameAs, child_other) }
           .not_to change { other.persistence_strategy.parent }
       end
     end