Rename ArraySerializer to CollectionSerializer for clarity

.rubocop_todo.yml

@@ -71,7 +71,7 @@ Style/BracesAroundHashParameters:
     - 'test/adapter/json_api/pagination_links_test.rb'
     - 'test/adapter/null_test.rb'
     - 'test/adapter_test.rb'
-    - 'test/array_serializer_test.rb'
+    - 'test/collection_serializer_test.rb'
     - 'test/serializable_resource_test.rb'
     - 'test/serializers/associations_test.rb'
     - 'test/serializers/attribute_test.rb'

CHANGELOG.md

@@ -20,6 +20,8 @@ Features:
 - [#1127](https://github.com/rails-api/active_model_serializers/pull/1127) Add support for nested
     associations for JSON and Attributes adapters via the `include` option (@NullVoxPopuli, @beauby).
 - [#1050](https://github.com/rails-api/active_model_serializers/pull/1050) Add support for toplevel jsonapi member (@beauby, @bf4)
+- [#tbd](https://github.com/rails-api/active_model_serializers/pull/tbd) Rename ArraySerializer to
+    CollectionSerializer for clarity, add ActiveModelSerializers.config.collection_serializer (@bf4)
 
 Fixes:
 - [#1239](https://github.com/rails-api/active_model_serializers/pull/1239) Fix duplicates in JSON API compound documents (@beauby)

README.md

@@ -120,7 +120,7 @@ If you wish to use a serializer other than the default, you can explicitly pass
 #### 2. For an array resource:
 
 ```ruby
-# Use the default `ArraySerializer`, which will use `each_serializer` to
+# Use the default `CollectionSerializer`, which will use `each_serializer` to
 # serialize each element
 render json: @posts, each_serializer: PostPreviewSerializer
 

docs/howto/add_pagination_links.md

@@ -75,7 +75,7 @@ render json: @posts, serializer: PaginatedSerializer, each_serializer: PostPrevi
 
 And then, you could do something like the following class.
 ```ruby
-class PaginatedSerializer < ActiveModel::Serializer::ArraySerializer
+class PaginatedSerializer < ActiveModel::Serializer::CollectionSerializer
   def initialize(object, options={})
     meta_key = options[:meta_key] || :meta
     options[meta_key] ||= {}

lib/action_controller/serialization.rb

@@ -31,7 +31,7 @@ module ActionController
         serializable_resource.serialization_scope_name = _serialization_scope
         begin
           serializable_resource.adapter
-        rescue ActiveModel::Serializer::ArraySerializer::NoSerializerError
+        rescue ActiveModel::Serializer::CollectionSerializer::NoSerializerError
           resource
         end
       else

lib/active_model/serializer.rb

@@ -1,4 +1,5 @@
 require 'thread_safe'
+require 'active_model/serializer/collection_serializer'
 require 'active_model/serializer/array_serializer'
 require 'active_model/serializer/include_tree'
 require 'active_model/serializer/associations'
@@ -105,7 +106,7 @@ module ActiveModel
       if resource.respond_to?(:serializer_class)
         resource.serializer_class
       elsif resource.respond_to?(:to_ary)
-        config.array_serializer
+        config.collection_serializer
       else
         options.fetch(:serializer) { get_serializer_for(resource.class) }
       end

lib/active_model/serializer/array_serializer.rb

@@ -1,41 +1,9 @@
-module ActiveModel
-  class Serializer
-    class ArraySerializer
-      NoSerializerError = Class.new(StandardError)
-      include Enumerable
-      delegate :each, to: :@serializers
-
-      attr_reader :object, :root
-
-      def initialize(resources, options = {})
-        @root = options[:root]
-        @object = resources
-        @serializers = resources.map do |resource|
-          serializer_context_class = options.fetch(:serializer_context_class, ActiveModel::Serializer)
-          serializer_class = options.fetch(:serializer) { serializer_context_class.serializer_for(resource) }
-
-          if serializer_class.nil?
-            fail NoSerializerError, "No serializer found for resource: #{resource.inspect}"
-          else
-            serializer_class.new(resource, options.except(:serializer))
-          end
-        end
-      end
-
-      def json_key
-        key = root || serializers.first.try(:json_key) || object.try(:name).try(:underscore)
-        key.try(:pluralize)
-      end
-
-      def paginated?
-        object.respond_to?(:current_page) &&
-          object.respond_to?(:total_pages) &&
-          object.respond_to?(:size)
-      end
-
-      protected
-
-      attr_reader :serializers
+require 'active_model/serializer/collection_serializer'
+class ActiveModel::Serializer
+  class ArraySerializer < CollectionSerializer
+    def initialize(*)
+      warn "Calling deprecated ArraySerializer in #{caller[0]}. Please use CollectionSerializer"
+      super
     end
   end
 end

lib/active_model/serializer/collection_serializer.rb

@@ -0,0 +1,41 @@
+module ActiveModel
+  class Serializer
+    class CollectionSerializer
+      NoSerializerError = Class.new(StandardError)
+      include Enumerable
+      delegate :each, to: :@serializers
+
+      attr_reader :object, :root
+
+      def initialize(resources, options = {})
+        @root = options[:root]
+        @object = resources
+        @serializers = resources.map do |resource|
+          serializer_context_class = options.fetch(:serializer_context_class, ActiveModel::Serializer)
+          serializer_class = options.fetch(:serializer) { serializer_context_class.serializer_for(resource) }
+
+          if serializer_class.nil?
+            fail NoSerializerError, "No serializer found for resource: #{resource.inspect}"
+          else
+            serializer_class.new(resource, options.except(:serializer))
+          end
+        end
+      end
+
+      def json_key
+        key = root || serializers.first.try(:json_key) || object.try(:name).try(:underscore)
+        key.try(:pluralize)
+      end
+
+      def paginated?
+        object.respond_to?(:current_page) &&
+          object.respond_to?(:total_pages) &&
+          object.respond_to?(:size)
+      end
+
+      protected
+
+      attr_reader :serializers
+    end
+  end
+end

lib/active_model/serializer/configuration.rb

@@ -7,9 +7,19 @@ module ActiveModel
       # Configuration options may also be set in
       # Serializers and Adapters
       included do |base|
-        base.config.array_serializer = ActiveModel::Serializer::ArraySerializer
-        base.config.adapter = :attributes
-        base.config.jsonapi_resource_type = :plural
+        config = base.config
+        config.collection_serializer = ActiveModel::Serializer::CollectionSerializer
+
+        def config.array_serializer=(collection_serializer)
+          self.collection_serializer = collection_serializer
+        end
+
+        def config.array_serializer
+          collection_serializer
+        end
+
+        config.adapter = :attributes
+        config.jsonapi_resource_type = :plural
       end
     end
   end

lib/active_model/serializer/reflection.rb

@@ -50,7 +50,7 @@ module ActiveModel
               association_value,
               serializer_options(subject, parent_serializer_options, reflection_options)
             )
-          rescue ActiveModel::Serializer::ArraySerializer::NoSerializerError
+          rescue ActiveModel::Serializer::CollectionSerializer::NoSerializerError
             reflection_options[:virtual_value] = association_value.try(:as_json) || association_value
           end
         elsif !association_value.nil? && !association_value.instance_of?(Object)

test/adapter/json/collection_test.rb

@@ -23,7 +23,7 @@ module ActiveModel
           def test_with_serializer_option
             @blog.special_attribute = 'Special'
             @blog.articles = [@first_post, @second_post]
-            serializer = ArraySerializer.new([@blog], serializer: CustomBlogSerializer)
+            serializer = CollectionSerializer.new([@blog], serializer: CustomBlogSerializer)
             adapter = ActiveModel::Serializer::Adapter::Json.new(serializer)
 
             expected = { blogs: [{
@@ -35,7 +35,7 @@ module ActiveModel
           end
 
           def test_include_multiple_posts
-            serializer = ArraySerializer.new([@first_post, @second_post])
+            serializer = CollectionSerializer.new([@first_post, @second_post])
             adapter = ActiveModel::Serializer::Adapter::Json.new(serializer)
 
             expected = { posts: [{
@@ -70,14 +70,14 @@ module ActiveModel
 
           def test_root_is_underscored
             virtual_value = VirtualValue.new(id: 1)
-            serializer = ArraySerializer.new([virtual_value])
+            serializer = CollectionSerializer.new([virtual_value])
             adapter = ActiveModel::Serializer::Adapter::Json.new(serializer)
 
             assert_equal 1, adapter.serializable_hash[:virtual_values].length
           end
 
           def test_include_option
-            serializer = ArraySerializer.new([@first_post, @second_post])
+            serializer = CollectionSerializer.new([@first_post, @second_post])
             adapter = ActiveModel::Serializer::Adapter::Json.new(serializer, include: '')
             actual = adapter.serializable_hash
             expected = { posts: [{ id: 1, title: 'Hello!!', body: 'Hello, world!!' },

test/adapter/json_api/collection_test.rb

@@ -19,7 +19,7 @@ module ActiveModel
             @second_post.author = @author
             @author.posts = [@first_post, @second_post]
 
-            @serializer = ArraySerializer.new([@first_post, @second_post])
+            @serializer = CollectionSerializer.new([@first_post, @second_post])
             @adapter = ActiveModel::Serializer::Adapter::JsonApi.new(@serializer)
             ActionController::Base.cache_store.clear
           end

test/adapter/json_api/linked_test.rb

@@ -45,7 +45,7 @@ module ActiveModel
           end
 
           def test_include_multiple_posts_and_linked_array
-            serializer = ArraySerializer.new([@first_post, @second_post])
+            serializer = CollectionSerializer.new([@first_post, @second_post])
             adapter = ActiveModel::Serializer::Adapter::JsonApi.new(
               serializer,
               include: [:comments, author: [:bio]]
@@ -226,7 +226,7 @@ module ActiveModel
           end
 
           def test_multiple_references_to_same_resource
-            serializer = ArraySerializer.new([@first_comment, @second_comment])
+            serializer = CollectionSerializer.new([@first_comment, @second_comment])
             adapter = ActiveModel::Serializer::Adapter::JsonApi.new(
               serializer,
               include: [:post]

test/array_serializer_test.rb

@@ -1,92 +1,21 @@
 require 'test_helper'
+require_relative 'collection_serializer_test'
 
 module ActiveModel
   class Serializer
-    class ArraySerializerTest < Minitest::Test
-      def setup
-        @comment = Comment.new
-        @post = Post.new
-        @resource = build_named_collection @comment, @post
-        @serializer = ArraySerializer.new(@resource, { some: :options })
+    class ArraySerializerTest < CollectionSerializerTest
+      extend ActiveSupport::Testing::Stream
+      def self.run_one_method(*)
+        stderr = (capture(:stderr) do
+          super
+        end)
+        if stderr !~ /Calling deprecated ArraySerializer/
+          fail Minitest::Assertion, stderr
+        end
       end
 
-      def build_named_collection(*resource)
-        resource.define_singleton_method(:name) { 'MeResource' }
-        resource
-      end
-
-      def test_has_object_reader_serializer_interface
-        assert_equal @serializer.object, @resource
-      end
-
-      def test_respond_to_each
-        assert_respond_to @serializer, :each
-      end
-
-      def test_each_object_should_be_serialized_with_appropriate_serializer
-        serializers =  @serializer.to_a
-
-        assert_kind_of CommentSerializer, serializers.first
-        assert_kind_of Comment, serializers.first.object
-
-        assert_kind_of PostSerializer, serializers.last
-        assert_kind_of Post, serializers.last.object
-
-        assert_equal serializers.last.custom_options[:some], :options
-      end
-
-      def test_serializer_option_not_passed_to_each_serializer
-        serializers = ArraySerializer.new([@post], { serializer: PostSerializer }).to_a
-
-        refute serializers.first.custom_options.key?(:serializer)
-      end
-
-      def test_root_default
-        @serializer = ArraySerializer.new([@comment, @post])
-        assert_equal @serializer.root, nil
-      end
-
-      def test_root
-        expected =  'custom_root'
-        @serializer = ArraySerializer.new([@comment, @post], root: expected)
-        assert_equal @serializer.root, expected
-      end
-
-      def test_root_with_no_serializers
-        expected =  'custom_root'
-        @serializer = ArraySerializer.new([], root: expected)
-        assert_equal @serializer.root, expected
-      end
-
-      def test_json_key
-        assert_equal @serializer.json_key, 'comments'
-      end
-
-      def test_json_key_with_resource_with_name_and_no_serializers
-        serializer = ArraySerializer.new(build_named_collection)
-        assert_equal serializer.json_key, 'me_resources'
-      end
-
-      def test_json_key_with_resource_with_nil_name_and_no_serializers
-        resource = []
-        resource.define_singleton_method(:name) { nil }
-        serializer = ArraySerializer.new(resource)
-        assert_equal serializer.json_key, nil
-      end
-
-      def test_json_key_with_resource_without_name_and_no_serializers
-        serializer = ArraySerializer.new([])
-        assert_equal serializer.json_key, nil
-      end
-
-      def test_json_key_with_root
-        serializer = ArraySerializer.new(@resource, root: 'custom_root')
-        assert_equal serializer.json_key, 'custom_roots'
-      end
-
-      def test_json_key_with_root_and_no_serializers
-        serializer = ArraySerializer.new(build_named_collection, root: 'custom_root')
-        assert_equal serializer.json_key, 'custom_roots'
+      def collection_serializer
+        ArraySerializer
       end
     end
   end

test/collection_serializer_test.rb

@@ -0,0 +1,97 @@
+require 'test_helper'
+
+module ActiveModel
+  class Serializer
+    class CollectionSerializerTest < Minitest::Test
+      def setup
+        @comment = Comment.new
+        @post = Post.new
+        @resource = build_named_collection @comment, @post
+        @serializer = collection_serializer.new(@resource, { some: :options })
+      end
+
+      def collection_serializer
+        CollectionSerializer
+      end
+
+      def build_named_collection(*resource)
+        resource.define_singleton_method(:name) { 'MeResource' }
+        resource
+      end
+
+      def test_has_object_reader_serializer_interface
+        assert_equal @serializer.object, @resource
+      end
+
+      def test_respond_to_each
+        assert_respond_to @serializer, :each
+      end
+
+      def test_each_object_should_be_serialized_with_appropriate_serializer
+        serializers =  @serializer.to_a
+
+        assert_kind_of CommentSerializer, serializers.first
+        assert_kind_of Comment, serializers.first.object
+
+        assert_kind_of PostSerializer, serializers.last
+        assert_kind_of Post, serializers.last.object
+
+        assert_equal serializers.last.custom_options[:some], :options
+      end
+
+      def test_serializer_option_not_passed_to_each_serializer
+        serializers = collection_serializer.new([@post], { serializer: PostSerializer }).to_a
+
+        refute serializers.first.custom_options.key?(:serializer)
+      end
+
+      def test_root_default
+        @serializer = collection_serializer.new([@comment, @post])
+        assert_equal @serializer.root, nil
+      end
+
+      def test_root
+        expected =  'custom_root'
+        @serializer = collection_serializer.new([@comment, @post], root: expected)
+        assert_equal @serializer.root, expected
+      end
+
+      def test_root_with_no_serializers
+        expected =  'custom_root'
+        @serializer = collection_serializer.new([], root: expected)
+        assert_equal @serializer.root, expected
+      end
+
+      def test_json_key
+        assert_equal @serializer.json_key, 'comments'
+      end
+
+      def test_json_key_with_resource_with_name_and_no_serializers
+        serializer = collection_serializer.new(build_named_collection)
+        assert_equal serializer.json_key, 'me_resources'
+      end
+
+      def test_json_key_with_resource_with_nil_name_and_no_serializers
+        resource = []
+        resource.define_singleton_method(:name) { nil }
+        serializer = collection_serializer.new(resource)
+        assert_equal serializer.json_key, nil
+      end
+
+      def test_json_key_with_resource_without_name_and_no_serializers
+        serializer = collection_serializer.new([])
+        assert_equal serializer.json_key, nil
+      end
+
+      def test_json_key_with_root
+        serializer = collection_serializer.new(@resource, root: 'custom_root')
+        assert_equal serializer.json_key, 'custom_roots'
+      end
+
+      def test_json_key_with_root_and_no_serializers
+        serializer = collection_serializer.new(build_named_collection, root: 'custom_root')
+        assert_equal serializer.json_key, 'custom_roots'
+      end
+    end
+  end
+end

test/fixtures/poro.rb

@@ -154,7 +154,7 @@ BlogSerializer = Class.new(ActiveModel::Serializer) do
   has_many :articles
 end
 
-PaginatedSerializer = Class.new(ActiveModel::Serializer::ArraySerializer) do
+PaginatedSerializer = Class.new(ActiveModel::Serializer::CollectionSerializer) do
   def json_key
     'paginated'
   end

test/serializers/associations_test.rb

@@ -33,13 +33,13 @@ module ActiveModel
           case key
           when :posts
             assert_equal({}, options)
-            assert_kind_of(ActiveModel::Serializer.config.array_serializer, serializer)
+            assert_kind_of(ActiveModel::Serializer.config.collection_serializer, serializer)
           when :bio
             assert_equal({}, options)
             assert_nil serializer
           when :roles
             assert_equal({}, options)
-            assert_kind_of(ActiveModel::Serializer.config.array_serializer, serializer)
+            assert_kind_of(ActiveModel::Serializer.config.collection_serializer, serializer)
           else
             flunk "Unknown association: #{key}"
           end

test/serializers/configuration_test.rb

@@ -3,8 +3,25 @@ require 'test_helper'
 module ActiveModel
   class Serializer
     class ConfigurationTest < Minitest::Test
+      def test_collection_serializer
+        assert_equal ActiveModel::Serializer::CollectionSerializer, ActiveModel::Serializer.config.collection_serializer
+      end
+
       def test_array_serializer
-        assert_equal ActiveModel::Serializer::ArraySerializer, ActiveModel::Serializer.config.array_serializer
+        assert_equal ActiveModel::Serializer::CollectionSerializer, ActiveModel::Serializer.config.array_serializer
+      end
+
+      def test_setting_array_serializer_sets_collection_serializer
+        config = ActiveModel::Serializer.config
+        old_config = config.dup
+        begin
+          assert_equal ActiveModel::Serializer::CollectionSerializer, config.collection_serializer
+          config.array_serializer = :foo
+          assert_equal config.array_serializer, :foo
+          assert_equal config.collection_serializer, :foo
+        ensure
+          ActiveModel::Serializer.config.replace(old_config)
+        end
       end
 
       def test_default_adapter

test/serializers/serializer_for_test.rb

@@ -3,26 +3,26 @@ require 'test_helper'
 module ActiveModel
   class Serializer
     class SerializerForTest < Minitest::Test
-      class ArraySerializerTest < Minitest::Test
+      class CollectionSerializerTest < Minitest::Test
         def setup
           @array = [1, 2, 3]
-          @previous_array_serializer = ActiveModel::Serializer.config.array_serializer
+          @previous_collection_serializer = ActiveModel::Serializer.config.collection_serializer
         end
 
         def teardown
-          ActiveModel::Serializer.config.array_serializer = @previous_array_serializer
+          ActiveModel::Serializer.config.collection_serializer = @previous_collection_serializer
         end
 
         def test_serializer_for_array
           serializer = ActiveModel::Serializer.serializer_for(@array)
-          assert_equal ActiveModel::Serializer.config.array_serializer, serializer
+          assert_equal ActiveModel::Serializer.config.collection_serializer, serializer
         end
 
         def test_overwritten_serializer_for_array
-          new_array_serializer = Class.new
-          ActiveModel::Serializer.config.array_serializer = new_array_serializer
+          new_collection_serializer = Class.new
+          ActiveModel::Serializer.config.collection_serializer = new_collection_serializer
           serializer = ActiveModel::Serializer.serializer_for(@array)
-          assert_equal new_array_serializer, serializer
+          assert_equal new_collection_serializer, serializer
         end
       end