Optimise recording deps on new items

lib/nanoc/base/repos/dependency_store.rb

@@ -11,7 +11,8 @@ def initialize(objects, env_name: nil)
       super(Nanoc::Int::Store.tmp_path_for(env_name: env_name, store_name: 'dependencies'), 4)
 
       @objects = objects
-      @graph   = Nanoc::Int::DirectedGraph.new([nil] + @objects)
+      @new_objects = []
+      @graph = Nanoc::Int::DirectedGraph.new([nil] + @objects)
     end
 
     contract C::Or[Nanoc::Int::Item, Nanoc::Int::ItemRep, Nanoc::Int::Layout] => C::ArrayOf[Nanoc::Int::Dependency]
@@ -50,7 +51,11 @@ def dependencies_causing_outdatedness_of(object)
     # predecessors of
     #   the given object
     def objects_causing_outdatedness_of(object)
-      @graph.direct_predecessors_of(object)
+      if @new_objects.any?
+        [@new_objects.first]
+      else
+        @graph.direct_predecessors_of(object)
+      end
     end
 
     # Returns the direct inverse dependencies for the given object.
@@ -67,7 +72,11 @@ def objects_causing_outdatedness_of(object)
     # @return [Array<Nanoc::Int::Item, Nanoc::Int::Layout>] The direct successors of
     #   the given object
     def objects_outdated_due_to(object)
-      @graph.direct_successors_of(object).compact
+      if @new_objects.include?(object)
+        @objects
+      else
+        @graph.direct_successors_of(object).compact
+      end
     end
 
     contract C::Maybe[C::Or[Nanoc::Int::Item, Nanoc::Int::Layout]], C::Maybe[C::Or[Nanoc::Int::Item, Nanoc::Int::Layout]], C::KeywordArgs[raw_content: C::Optional[C::Bool], attributes: C::Optional[C::Bool], compiled_content: C::Optional[C::Bool], path: C::Optional[C::Bool]] => C::Any
@@ -141,14 +150,7 @@ def data=(new_data)
       end
 
       # Record dependency from all items on new items
-      new_objects = (@objects - previous_objects)
-      new_props = { raw_content: true, attributes: true, compiled_content: true, path: true }
-      new_objects.each do |new_obj|
-        @objects.each do |obj|
-          next unless obj.is_a?(Nanoc::Int::Item)
-          @graph.add_edge(new_obj, obj, props: new_props)
-        end
-      end
+      @new_objects = @objects - previous_objects
     end
   end
 end

spec/nanoc/base/repos/dependency_store_spec.rb

@@ -121,30 +121,80 @@
       store.record_dependency(obj_a, obj_b, attributes: true)
 
       store.store
+      store.objects = objects_after
       store.load
     end
 
-    it 'has the right dependencies for item A' do
-      deps = store.dependencies_causing_outdatedness_of(obj_a)
-      expect(deps.size).to eql(1)
+    context 'no new objects' do
+      let(:objects_after) { objects }
 
-      expect(deps[0].from).to eql(obj_b)
-      expect(deps[0].to).to eql(obj_a)
+      it 'has the right dependencies for item A' do
+        deps = store.dependencies_causing_outdatedness_of(obj_a)
+        expect(deps.size).to eql(1)
+
+        expect(deps[0].from).to eql(obj_b)
+        expect(deps[0].to).to eql(obj_a)
+
+        expect(deps[0].props.raw_content?).to eq(false)
+        expect(deps[0].props.attributes?).to eq(true)
+        expect(deps[0].props.compiled_content?).to eq(true)
+        expect(deps[0].props.path?).to eq(false)
+      end
 
-      expect(deps[0].props.raw_content?).to eq(false)
-      expect(deps[0].props.attributes?).to eq(true)
-      expect(deps[0].props.compiled_content?).to eq(true)
-      expect(deps[0].props.path?).to eq(false)
+      it 'has the right dependencies for item B' do
+        deps = store.dependencies_causing_outdatedness_of(obj_b)
+        expect(deps).to be_empty
+      end
+
+      it 'has the right dependencies for item C' do
+        deps = store.dependencies_causing_outdatedness_of(obj_c)
+        expect(deps).to be_empty
+      end
     end
 
-    it 'has the right dependencies for item B' do
-      deps = store.dependencies_causing_outdatedness_of(obj_b)
-      expect(deps).to be_empty
+    context 'one new object' do
+      let(:objects_after) do
+        [obj_a, obj_b, obj_c, obj_d]
+      end
+
+      let(:obj_d) { Nanoc::Int::Item.new('d', {}, '/d.md') }
+
+      it 'marks existing items as outdated' do
+        expect(store.objects_causing_outdatedness_of(obj_a)).to eq([obj_d])
+        expect(store.objects_causing_outdatedness_of(obj_b)).to eq([obj_d])
+        expect(store.objects_causing_outdatedness_of(obj_c)).to eq([obj_d])
+      end
+
+      it 'has the right target dependencies' do
+        expect(store.objects_outdated_due_to(obj_a)).to be_empty
+        expect(store.objects_outdated_due_to(obj_b)).to eq([obj_a])
+        expect(store.objects_outdated_due_to(obj_c)).to be_empty
+        expect(store.objects_outdated_due_to(obj_d)).to eq(objects_after)
+      end
     end
 
-    it 'has the right dependencies for item C' do
-      deps = store.dependencies_causing_outdatedness_of(obj_c)
-      expect(deps).to be_empty
+    context 'two new objects' do
+      let(:objects_after) do
+        [obj_a, obj_b, obj_c, obj_d, obj_e]
+      end
+
+      let(:obj_d) { Nanoc::Int::Item.new('d', {}, '/d.md') }
+      let(:obj_e) { Nanoc::Int::Item.new('e', {}, '/e.md') }
+
+      it 'marks existing items as outdated' do
+        # Only one of obj D or E needed!
+        expect(store.objects_causing_outdatedness_of(obj_a)).to eq([obj_d]).or eq([obj_e])
+        expect(store.objects_causing_outdatedness_of(obj_b)).to eq([obj_d]).or eq([obj_e])
+        expect(store.objects_causing_outdatedness_of(obj_c)).to eq([obj_d]).or eq([obj_e])
+      end
+
+      it 'has the right target dependencies' do
+        expect(store.objects_outdated_due_to(obj_a)).to be_empty
+        expect(store.objects_outdated_due_to(obj_b)).to eq([obj_a])
+        expect(store.objects_outdated_due_to(obj_c)).to be_empty
+        expect(store.objects_outdated_due_to(obj_d)).to eq(objects_after)
+        expect(store.objects_outdated_due_to(obj_e)).to eq(objects_after)
+      end
     end
   end
 end