Merge pull request #5116 from Shopify/elvin/fix-extension-instantiation

bug fix: extensions can register more extensions via apply method

lib/graphql/schema/field.rb

@@ -313,7 +313,7 @@ def initialize(type: nil, name: nil, owner: nil, null: nil, description: NOT_CON
         @ast_node = ast_node
         @method_conflict_warning = method_conflict_warning
         @fallback_value = fallback_value
-        @definition_block = nil
+        @definition_block = definition_block
 
         arguments.each do |name, arg|
           case arg
@@ -332,14 +332,15 @@ def initialize(type: nil, name: nil, owner: nil, null: nil, description: NOT_CON
         @subscription_scope = subscription_scope
 
         @extensions = EMPTY_ARRAY
+        @call_after_define = false
         set_pagination_extensions(connection_extension: connection_extension)
         # Do this last so we have as much context as possible when initializing them:
         if extensions.any?
-          self.extensions(extensions, call_after_define: false)
+          self.extensions(extensions)
         end
 
         if resolver_class && resolver_class.extensions.any?
-          self.extensions(resolver_class.extensions, call_after_define: false)
+          self.extensions(resolver_class.extensions)
         end
 
         if directives.any?
@@ -352,10 +353,9 @@ def initialize(type: nil, name: nil, owner: nil, null: nil, description: NOT_CON
           self.validates(validates)
         end
 
-        if block_given?
-          @definition_block = definition_block
-        else
+        if @definition_block.nil?
           self.extensions.each(&:after_define_apply)
+          @call_after_define = true
         end
       end
 
@@ -372,6 +372,7 @@ def ensure_loaded
             instance_eval(&@definition_block)
           end
           self.extensions.each(&:after_define_apply)
+          @call_after_define = true
           @definition_block = nil
         end
         self
@@ -435,14 +436,14 @@ def comment(text = nil)
       #
       # @param extensions [Array<Class, Hash<Class => Hash>>] Add extensions to this field. For hash elements, only the first key/value is used.
       # @return [Array<GraphQL::Schema::FieldExtension>] extensions to apply to this field
-      def extensions(new_extensions = nil, call_after_define: !@definition_block)
+      def extensions(new_extensions = nil)
         if new_extensions
           new_extensions.each do |extension_config|
             if extension_config.is_a?(Hash)
               extension_class, options = *extension_config.to_a[0]
-              self.extension(extension_class, call_after_define: call_after_define, **options)
+              self.extension(extension_class, **options)
             else
-              self.extension(extension_config, call_after_define: call_after_define)
+              self.extension(extension_config)
             end
           end
         end
@@ -460,12 +461,12 @@ def extensions(new_extensions = nil, call_after_define: !@definition_block)
       # @param extension_class [Class] subclass of {Schema::FieldExtension}
       # @param options [Hash] if provided, given as `options:` when initializing `extension`.
       # @return [void]
-      def extension(extension_class, call_after_define: !@definition_block, **options)
+      def extension(extension_class, **options)
         extension_inst = extension_class.new(field: self, options: options)
         if @extensions.frozen?
           @extensions = @extensions.dup
         end
-        if call_after_define
+        if @call_after_define
           extension_inst.after_define_apply
         end
         @extensions << extension_inst

spec/graphql/schema/field_extension_spec.rb

@@ -94,6 +94,18 @@ def after_resolve(value:, object:, **_args)
       end
     end
 
+    class AddNestedExtensionExtension < GraphQL::Schema::FieldExtension
+      def apply
+        field.extension(NestedExtension)
+      end
+
+      class NestedExtension < GraphQL::Schema::FieldExtension
+        def resolve(**_args)
+          1
+        end
+      end
+    end
+
     class BaseObject < GraphQL::Schema::Object
     end
 
@@ -154,6 +166,8 @@ def pass_thru_without_splat(input:)
       end
 
       field :object_class_test, [String], null: false, extensions: [ObjectClassExtension]
+
+      field :nested_extension, Integer, null: false, extensions: [AddNestedExtensionExtension]
     end
 
     class Schema < GraphQL::Schema
@@ -236,6 +250,13 @@ def exec_query(query_str, **kwargs)
     end
   end
 
+  describe "nested extension in apply method" do
+    it "applies the nested extension" do
+      res = exec_query("{ nestedExtension }")
+      assert_equal 1, res["data"]["nestedExtension"]
+    end
+  end
+
   describe "after_define" do
     class AfterDefineThing < GraphQL::Schema::Object
       class AfterDefineExtension < GraphQL::Schema::FieldExtension