implement saving of nested forms in Save. fixes #73 and #37.

lib/reform/form/save.rb

@@ -1,14 +1,34 @@
 class Reform::Form
   module Save
+    module OnNested
+      def to_hash(*)
+        # process output from InputRepresenter {title: "Mint Car", hit: <Form>}
+        # and just call sync! on nested forms.
+        nested_forms do |attr|
+          attr.merge!(
+            :instance     => lambda { |fragment, *| fragment },
+            :serialize => lambda { |object, *| object.save! },
+          )
+        end
+
+        super
+      end
+    end
+
     def save
       # DISCUSS: we should never hit @mapper here (which writes to the models) when a block is passed.
       return yield self, to_nested_hash if block_given?
 
-      sync_models
-      save_models
+      sync_models # recursion
+      save!
+    end
+
+    def save!
+      save_model
+      mapper.new(self).extend(OnNested).to_hash # save! on all nested forms.
     end
 
-    def save_models
+    def save_model
       model.save # TODO: implement nested (that should really be done by Twin/AR).
     end
   end

test/form_composition_test.rb

@@ -1,17 +1,5 @@
 require 'test_helper'
 
-MiniTest::Spec.class_eval do
-  module Saveable
-    def save
-      @saved = true
-    end
-
-    def saved?
-      @saved
-    end
-  end
-end
-
 class FormCompositionTest < MiniTest::Spec
   Song      = Struct.new(:id, :title)
   Requester = Struct.new(:id, :name)

test/save_test.rb

@@ -0,0 +1,45 @@
+require 'test_helper'
+
+class SaveTest < BaseTest
+  describe "populated" do
+    let (:params) {
+      {
+        "title" => "Best Of",
+        "hit"   => {"title" => "Roxanne"},
+        "songs" => [{"title" => "Fallout"}, {"title" => "Roxanne"}],
+        :band  => {:label => {:name => "Polydor"}}
+      }
+    }
+
+    let (:album) { Album.new(nil, hit, [song1, song2], band) }
+    let (:hit) { Song.new }
+    let (:song1) { Song.new }
+    let (:song2) { Song.new }
+    let (:band) { Band.new(label) }
+    let (:label) { Label.new }
+
+    subject { ErrorsTest::AlbumForm.new(album) }
+
+    before do
+      [album, hit, song1, song2, band, label].each { |mdl| mdl.extend(Saveable) }
+
+      subject.validate(params)
+      subject.save
+    end
+
+    # synced?
+    it { album.title.must_equal "Best Of" }
+    it { hit.title.must_equal "Roxanne" }
+    it { song1.title.must_equal "Fallout" }
+    it { song2.title.must_equal "Roxanne" }
+    it { label.name.must_equal "Polydor" }
+
+    # saved?
+    it { album.saved?.must_equal true }
+    it { hit.saved?.must_equal true }
+    it { song1.saved?.must_equal true }
+    it { song1.saved?.must_equal true }
+    it { band.saved?.must_equal true }
+    it { label.saved?.must_equal true }
+  end
+end