Fix root/meta for ArraySerializer

Author: ryansch

lib/active_model/serializer/adapter/json.rb

@@ -4,6 +4,11 @@ module ActiveModel
   class Serializer
     class Adapter
       class Json < Adapter
+        def initialize(serializer, options = {})
+          super
+          serializer.root = true if @options[:root]
+        end
+
         def serializable_hash(options = {})
           if serializer.respond_to?(:each)
             @result = serializer.map{|s| self.class.new(s).serializable_hash }

lib/active_model/serializer/array_serializer.rb

@@ -4,9 +4,10 @@ class ArraySerializer
       include Enumerable
       delegate :each, to: :@objects
 
-      attr_reader :meta, :meta_key
+      attr_accessor :meta, :meta_key, :root
 
       def initialize(objects, options = {})
+        @root = options[:root]
         options.merge!(root: nil)
 
         @objects = objects.map do |object|
@@ -21,11 +22,11 @@ def initialize(objects, options = {})
       end
 
       def json_key
-        @objects.first.json_key if @objects.first
-      end
-
-      def root=(root)
-        @objects.first.root = root if @objects.first
+        if root == true && @objects.first
+          @objects.first.class.root_name
+        else
+          root
+        end
       end
     end
   end

test/array_serializer_test.rb

@@ -38,6 +38,20 @@ def test_meta_and_meta_key_attr_readers
         assert_equal @serializer.meta, "the meta"
         assert_equal @serializer.meta_key, "the meta key"
       end
+
+      def test_root_attr_reader
+        root_content = {root: true}
+        @serializer = ArraySerializer.new([@comment, @post], root_content)
+
+        assert_equal true, @serializer.root
+      end
+
+      def test_root_attr_reader_with_empty_array
+        root_content = {root: true}
+        @serializer = ArraySerializer.new([], root_content)
+
+        assert_equal @serializer.root, true
+      end
     end
   end
 end

test/serializers/meta_test.rb

@@ -48,22 +48,27 @@ def test_meta_key_is_used
         assert_equal expected, adapter.as_json
       end
 
-      def test_meta_is_not_used_on_arrays
-        serializer = ArraySerializer.new([@blog], root: "blog", meta: {total: 10}, meta_key: "haha_meta")
-        adapter = ActiveModel::Serializer::Adapter::Json.new(serializer)
-        expected = [{
-          id: 1,
-          name: "AMS Hints",
-          writer: {
-            id: 2,
-            name: "Steve"
-          },
-          articles: [{
-            id: 3,
-            title: "AMS",
-            body: nil
-          }]
-        }]
+      def test_meta_is_used_on_arrays
+        serializer = ArraySerializer.new([@blog], meta: {total: 10}, meta_key: "haha_meta")
+        adapter = ActiveModel::Serializer::Adapter::Json.new(serializer, root: 'blog')
+        expected = {
+          'blog' => [{
+            id: 1,
+            name: "AMS Hints",
+            writer: {
+              id: 2,
+              name: "Steve"
+            },
+            articles: [{
+              id: 3,
+              title: "AMS",
+              body: nil
+            }]
+          }],
+          'haha_meta' => {
+            total: 10
+          }
+        }
         assert_equal expected, adapter.as_json
       end