Introduce Adapter::Base

Author: bf4

.rubocop.yml

@@ -8,39 +8,6 @@ AllCops:
   DisplayCopNames: true
   DisplayStyleGuide: true
 
-Style/IndentationConsistency:
-  Exclude:
-    - lib/active_model/serializer/adapter/attributes.rb
-    - lib/active_model/serializer/adapter/fragment_cache.rb
-    - lib/active_model/serializer/adapter/json.rb
-    - lib/active_model/serializer/adapter/json/fragment_cache.rb
-    - lib/active_model/serializer/adapter/json_api.rb
-    - lib/active_model/serializer/adapter/json_api/fragment_cache.rb
-    - lib/active_model/serializer/adapter/json_api/pagination_links.rb
-    - lib/active_model/serializer/adapter/null.rb
-
-Style/IndentationWidth:
-  Exclude:
-    - lib/active_model/serializer/adapter/attributes.rb
-    - lib/active_model/serializer/adapter/fragment_cache.rb
-    - lib/active_model/serializer/adapter/json.rb
-    - lib/active_model/serializer/adapter/json/fragment_cache.rb
-    - lib/active_model/serializer/adapter/json_api.rb
-    - lib/active_model/serializer/adapter/json_api/fragment_cache.rb
-    - lib/active_model/serializer/adapter/json_api/pagination_links.rb
-    - lib/active_model/serializer/adapter/null.rb
-
-Style/AccessModifierIndentation:
-  Exclude:
-    - lib/active_model/serializer/adapter/attributes.rb
-    - lib/active_model/serializer/adapter/fragment_cache.rb
-    - lib/active_model/serializer/adapter/json.rb
-    - lib/active_model/serializer/adapter/json/fragment_cache.rb
-    - lib/active_model/serializer/adapter/json_api.rb
-    - lib/active_model/serializer/adapter/json_api/fragment_cache.rb
-    - lib/active_model/serializer/adapter/json_api/pagination_links.rb
-    - lib/active_model/serializer/adapter/null.rb
-
 Lint/NestedMethodDefinition:
   Enabled: false
   Exclude:

lib/active_model/serializer/adapter.rb

@@ -1,31 +1,34 @@
 module ActiveModel
   class Serializer
-    class Adapter
+    module Adapter
       UnknownAdapterError = Class.new(ArgumentError)
       ADAPTER_MAP = {}
       private_constant :ADAPTER_MAP if defined?(private_constant)
       extend ActiveSupport::Autoload
+      autoload :Base
       autoload :Attributes
       autoload :Null
       autoload :FragmentCache
       autoload :Json
       autoload :JsonApi
       autoload :CachedSerializer
 
-      def self.create(resource, options = {})
-        override = options.delete(:adapter)
-        klass = override ? adapter_class(override) : ActiveModel::Serializer.adapter
-        klass.new(resource, options)
-      end
+      class << self # All methods are class functions
+        def new(*args)
+          fail ArgumentError, [args, caller[0]].inspect
+        end
 
-      # @see ActiveModel::Serializer::Adapter.lookup
-      def self.adapter_class(adapter)
-        ActiveModel::Serializer::Adapter.lookup(adapter)
-      end
+        def create(resource, options = {})
+          override = options.delete(:adapter)
+          klass = override ? adapter_class(override) : ActiveModel::Serializer.adapter
+          klass.new(resource, options)
+        end
+
+        # @see ActiveModel::Serializer::Adapter.lookup
+        def adapter_class(adapter)
+          ActiveModel::Serializer::Adapter.lookup(adapter)
+        end
 
-      # Only the Adapter class has these methods.
-      # None of the sublasses have them.
-      class << ActiveModel::Serializer::Adapter
         # @return Hash<adapter_name, adapter_class>
         def adapter_map
           ADAPTER_MAP
@@ -80,57 +83,6 @@ def find_by_name(adapter_name)
         end
         private :find_by_name
       end
-
-      # Automatically register adapters when subclassing
-      def self.inherited(subclass)
-        ActiveModel::Serializer::Adapter.register(subclass)
-      end
-
-      attr_reader :serializer, :instance_options
-
-      def initialize(serializer, options = {})
-        @serializer = serializer
-        @instance_options = options
-      end
-
-      def serializable_hash(options = nil)
-        raise NotImplementedError, 'This is an abstract method. Should be implemented at the concrete adapter.'
-      end
-
-      def as_json(options = nil)
-        hash = serializable_hash(options)
-        include_meta(hash)
-        hash
-      end
-
-      def fragment_cache(*args)
-        raise NotImplementedError, 'This is an abstract method. Should be implemented at the concrete adapter.'
-      end
-
-      def cache_check(serializer)
-        CachedSerializer.new(serializer).cache_check(self) do
-          yield
-        end
-      end
-
-      private
-
-      def meta
-        serializer.meta if serializer.respond_to?(:meta)
-      end
-
-      def meta_key
-        serializer.meta_key || 'meta'.freeze
-      end
-
-      def root
-        serializer.json_key.to_sym if serializer.json_key
-      end
-
-      def include_meta(json)
-        json[meta_key] = meta if meta
-        json
-      end
     end
   end
 end

lib/active_model/serializer/adapter/attributes.rb

@@ -1,4 +1,7 @@
-class ActiveModel::Serializer::Adapter::Attributes < ActiveModel::Serializer::Adapter
+module ActiveModel
+  class Serializer
+    module Adapter
+      class Attributes < Base
         def serializable_hash(options = nil)
           options ||= {}
           if serializer.respond_to?(:each)
@@ -47,4 +50,7 @@ def fragment_cache(cached_hash, non_cached_hash)
         def include_meta(json)
           json
         end
+      end
+    end
+  end
 end

lib/active_model/serializer/adapter/base.rb

@@ -0,0 +1,58 @@
+module ActiveModel
+  class Serializer
+    module Adapter
+      class Base
+        # Automatically register adapters when subclassing
+        def self.inherited(subclass)
+          ActiveModel::Serializer::Adapter.register(subclass)
+        end
+
+        attr_reader :serializer, :instance_options
+
+        def initialize(serializer, options = {})
+          @serializer = serializer
+          @instance_options = options
+        end
+
+        def serializable_hash(_options = nil)
+          fail NotImplementedError, 'This is an abstract method. Should be implemented at the concrete adapter.'
+        end
+
+        def as_json(options = nil)
+          hash = serializable_hash(options)
+          include_meta(hash)
+          hash
+        end
+
+        def fragment_cache(*_args)
+          fail NotImplementedError, 'This is an abstract method. Should be implemented at the concrete adapter.'
+        end
+
+        def cache_check(serializer)
+          CachedSerializer.new(serializer).cache_check(self) do
+            yield
+          end
+        end
+
+        private
+
+        def meta
+          serializer.meta if serializer.respond_to?(:meta)
+        end
+
+        def meta_key
+          serializer.meta_key || 'meta'.freeze
+        end
+
+        def root
+          serializer.json_key.to_sym if serializer.json_key
+        end
+
+        def include_meta(json)
+          json[meta_key] = meta if meta
+          json
+        end
+      end
+    end
+  end
+end

lib/active_model/serializer/adapter/cached_serializer.rb

@@ -1,6 +1,6 @@
 module ActiveModel
   class Serializer
-    class Adapter
+    module Adapter
       class CachedSerializer
         def initialize(serializer)
           @cached_serializer = serializer

lib/active_model/serializer/adapter/fragment_cache.rb

@@ -1,4 +1,7 @@
-class ActiveModel::Serializer::Adapter::FragmentCache
+module ActiveModel
+  class Serializer
+    module Adapter
+      class FragmentCache
         attr_reader :serializer
 
         def initialize(adapter, serializer, options)
@@ -76,4 +79,7 @@ def fragment_serializer(name, klass)
         def to_valid_const_name(name)
           name.gsub('::', '_')
         end
+      end
+    end
+  end
 end

lib/active_model/serializer/adapter/json.rb

@@ -1,4 +1,7 @@
-class ActiveModel::Serializer::Adapter::Json < ActiveModel::Serializer::Adapter
+module ActiveModel
+  class Serializer
+    module Adapter
+      class Json < Base
         extend ActiveSupport::Autoload
         autoload :FragmentCache
 
@@ -12,4 +15,7 @@ def serializable_hash(options = nil)
         def fragment_cache(cached_hash, non_cached_hash)
           ActiveModel::Serializer::Adapter::Json::FragmentCache.new.fragment_cache(cached_hash, non_cached_hash)
         end
+      end
+    end
+  end
 end

lib/active_model/serializer/adapter/json/fragment_cache.rb

@@ -1,5 +1,13 @@
-class ActiveModel::Serializer::Adapter::Json::FragmentCache
+module ActiveModel
+  class Serializer
+    module Adapter
+      class Json
+        class FragmentCache
           def fragment_cache(cached_hash, non_cached_hash)
             non_cached_hash.merge cached_hash
           end
+        end
+      end
+    end
+  end
 end

lib/active_model/serializer/adapter/json_api.rb

@@ -1,4 +1,7 @@
-class ActiveModel::Serializer::Adapter::JsonApi < ActiveModel::Serializer::Adapter
+module ActiveModel
+  class Serializer
+    module Adapter
+      class JsonApi < Base
         extend ActiveSupport::Autoload
         autoload :PaginationLinks
         autoload :FragmentCache
@@ -157,4 +160,7 @@ def _included_for(serializer, includes)
         def links_for(serializer, options)
           JsonApi::PaginationLinks.new(serializer.object, options[:context]).serializable_hash(options)
         end
+      end
+    end
+  end
 end

lib/active_model/serializer/adapter/json_api/fragment_cache.rb

@@ -1,4 +1,8 @@
-class ActiveModel::Serializer::Adapter::JsonApi::FragmentCache
+module ActiveModel
+  class Serializer
+    module Adapter
+      class JsonApi
+        class FragmentCache
           def fragment_cache(root, cached_hash, non_cached_hash)
             hash              = {}
             core_cached       = cached_hash.first
@@ -10,4 +14,8 @@ def fragment_cache(root, cached_hash, non_cached_hash)
 
             hash.deep_merge no_root_non_cache.deep_merge no_root_cache
           end
+        end
+      end
+    end
+  end
 end

lib/active_model/serializer/adapter/json_api/pagination_links.rb

@@ -1,4 +1,8 @@
-class ActiveModel::Serializer::Adapter::JsonApi::PaginationLinks
+module ActiveModel
+  class Serializer
+    module Adapter
+      class JsonApi
+        class PaginationLinks
           FIRST_PAGE = 1
 
           attr_reader :collection, :context
@@ -47,4 +51,8 @@ def original_url
           def query_parameters
             @query_parameters ||= context.query_parameters
           end
+        end
+      end
+    end
+  end
 end

lib/active_model/serializer/adapter/null.rb

@@ -1,5 +1,11 @@
-class ActiveModel::Serializer::Adapter::Null < ActiveModel::Serializer::Adapter
+module ActiveModel
+  class Serializer
+    module Adapter
+      class Null < Base
         def serializable_hash(options = nil)
           {}
         end
+      end
+    end
+  end
 end

test/adapter/fragment_cache_test.rb

@@ -1,7 +1,7 @@
 require 'test_helper'
 module ActiveModel
   class Serializer
-    class Adapter
+    module Adapter
       class FragmentCacheTest < Minitest::Test
         def setup
           @spam            = Spam::UnrelatedLink.new(id: 'spam-id-1')

test/adapter/json/belongs_to_test.rb

@@ -2,7 +2,7 @@
 
 module ActiveModel
   class Serializer
-    class Adapter
+    module Adapter
       class Json
         class BelongsToTest < Minitest::Test
           def setup

test/adapter/json/collection_test.rb

@@ -2,7 +2,7 @@
 
 module ActiveModel
   class Serializer
-    class Adapter
+    module Adapter
       class Json
         class Collection < Minitest::Test
           def setup

test/adapter/json/has_many_test.rb

@@ -2,7 +2,7 @@
 
 module ActiveModel
   class Serializer
-    class Adapter
+    module Adapter
       class Json
         class HasManyTestTest < Minitest::Test
           def setup

test/adapter/json_api/belongs_to_test.rb

@@ -2,7 +2,7 @@
 
 module ActiveModel
   class Serializer
-    class Adapter
+    module Adapter
       class JsonApi
         class BelongsToTest < Minitest::Test
           def setup