Fix using passed values in callable attributes

It turned out it's not always possible to use the passed value in a block. Passing values requires more attention, there are open issues about it, but it's a nice improvement anyway

lib/rom/factory/tuple_evaluator.rb

@@ -151,9 +151,9 @@ def evaluate(traits, attrs, opts)
 
       # @api private
       def evaluate_values(attrs)
-        attributes.values.tsort.each_with_object({}) do |attr, h|
-          deps = attr.dependency_names.map { |k| h[k] }.compact
-          result = attr.(attrs, *deps)
+        attributes.values.tsort.each_with_object(attrs.dup) do |attr, h|
+          deps = attr.dependency_names.filter_map { |k| h[k] }
+          result = attr.(h, *deps)
 
           if result
             h.update(result)
@@ -162,7 +162,7 @@ def evaluate_values(attrs)
       end
 
       def evaluate_traits(trait_list, attrs, opts)
-        return {} if trait_list.empty?
+        return EMPTY_HASH if trait_list.empty?
 
         traits = trait_list.map { |v| v.is_a?(Hash) ? v : {v => true} }.reduce(:merge)
 

spec/integration/rom/factory_spec.rb

@@ -490,6 +490,43 @@
 
       expect(user.email).to eql("#{user.first_name}.#{user.last_name}@test-1.org")
     end
+
+    it "can use passed values in the block" do
+      factories.define(:user, relation: :users) do |f|
+        f.last_name { fake(:name) }
+        f.email { |first_name, last_name| "#{first_name}.#{last_name}@example.com" }
+        f.timestamps
+      end
+
+      user = factories[:user, first_name: "Jane"]
+
+      expect(user.email).to eql("Jane.#{user.last_name}@example.com")
+    end
+
+    it "can use passed values in the block" do
+      factories.define(:user, relation: :users) do |f|
+        f.first_name nil
+        f.last_name { fake(:name) }
+        f.email { |first_name| "#{first_name}@example.com" }
+        f.timestamps
+      end
+
+      user = factories[:user, first_name: "Jane"]
+
+      expect(user.email).to eql("[email protected]")
+    end
+
+    it "can use passed values in the block" do
+      factories.define(:user, relation: :users) do |f|
+        f.last_name { fake(:name) }
+        f.email { |first_name| "#{first_name}@example.com" }
+        f.timestamps
+      end
+
+      user = factories[:user, first_name: "Jane"]
+
+      expect(user.email).to eql("[email protected]")
+    end
   end
 
   context "changing values of dependant attributes" do