Fix MONGOID-4865 include_root_in_json setting retrieval does not resp…

…ect hierarchy

lib/mongoid/serializable.rb

@@ -13,10 +13,15 @@ module Serializable
     # We need to redefine where the JSON configuration is getting defined,
     # similar to +ActiveRecord+.
     included do
-      extend Forwardable
 
-      undef_method :include_root_in_json
-      def_delegator ::Mongoid, :include_root_in_json
+      class << self
+        extend Forwardable
+
+        # Note that this intentionally only delegates :include_root_in_json
+        # and not :include_root_in_json? - delegating the latter produces
+        # wrong behavior.
+        def_delegators ::Mongoid, :include_root_in_json
+      end
     end
 
     # Gets the document as a serializable hash, used by ActiveModel's JSON

spec/mongoid/serializable_spec.rb

@@ -16,31 +16,117 @@
     end
   end
 
-  describe ".include_root_in_json" do
+  %i(include_root_in_json include_root_in_json?).each do |meth|
+    describe ".#{meth}" do
 
-    let(:person) do
-      Person.new
-    end
+      before do
+        reload_model(:Minim)
+      end
 
-    context "when config set to true" do
+      after do
+        Mongoid.include_root_in_json = false
+        reload_model(:Minim)
+      end
 
-      before do
-        Mongoid.include_root_in_json = true
+      context "when global config is set to true" do
+
+        before do
+          Mongoid.include_root_in_json = true
+        end
+
+        it "returns true" do
+          expect(Minim.public_send(meth)).to be true
+        end
+
+        context 'when value is overridden to false in the model class' do
+          before do
+            Minim.include_root_in_json = false
+          end
+
+          it 'returns false' do
+            expect(Minim.public_send(meth)).to be false
+          end
+        end
       end
 
-      it "returns true" do
-        expect(person.include_root_in_json).to be true
+      context "when global config set to false" do
+
+        before do
+          Mongoid.include_root_in_json = false
+        end
+
+        it "returns false" do
+          expect(Minim.public_send(meth)).to be false
+        end
+
+        context 'when value is overridden to true in the model class' do
+          before do
+            Minim.include_root_in_json = true
+          end
+
+          it 'returns true' do
+            expect(Minim.public_send(meth)).to be true
+          end
+        end
       end
     end
 
-    context "when config set to false" do
+    describe "#include_root_in_json" do
 
       before do
+        reload_model(:Minim)
+      end
+
+      after do
         Mongoid.include_root_in_json = false
+        reload_model(:Minim)
+      end
+
+      let(:minim) do
+        Minim.new
+      end
+
+      context "when global config is set to true" do
+
+        before do
+          Minim.include_root_in_json.should be false
+          Mongoid.include_root_in_json = true
+        end
+
+        it "returns true" do
+          expect(minim.public_send(meth)).to be true
+        end
+
+        context 'when value is overridden to false in the model class' do
+          before do
+            Minim.include_root_in_json = false
+          end
+
+          it 'returns false' do
+            expect(minim.public_send(meth)).to be false
+          end
+        end
       end
 
-      it "returns false" do
-        expect(person.include_root_in_json).to be false
+      context "when global config set to false" do
+
+        before do
+          Mongoid.include_root_in_json = false
+        end
+
+        it "returns false" do
+          expect(minim.public_send(meth)).to be false
+        end
+
+        context 'when value is overridden to true in the model class' do
+          before do
+            Minim.include_root_in_json = true
+          end
+
+          it 'returns true' do
+            expect(minim.public_send(meth)).to be true
+          end
+        end
       end
     end
   end
@@ -773,32 +859,57 @@
 
   describe "#to_json" do
 
-    let(:person) do
-      Person.new
+    let(:account) do
+      Account.new
     end
 
-    context "when including root in json" do
+    context "when including root in json via Mongoid" do
 
       before do
+        account.include_root_in_json.should be false
         Mongoid.include_root_in_json = true
       end
 
+      after do
+        Mongoid.include_root_in_json = false
+      end
+
       it "uses the mongoid configuration" do
-        expect(person.to_json).to include("person")
+        expect(JSON.parse(account.to_json)).to have_key("account")
+      end
+    end
+
+    context "when including root in json via class" do
+
+      before do
+        account.include_root_in_json.should be false
+        Account.include_root_in_json = true
+      end
+
+      after do
+        Account.include_root_in_json = false
+      end
+
+      it "uses the class configuration" do
+        expect(JSON.parse(account.to_json)).to have_key("account")
       end
     end
 
     context "when not including root in json" do
 
       before do
-        Mongoid.include_root_in_json = false
+        account.include_root_in_json.should be false
       end
 
       it "uses the mongoid configuration" do
-        expect(person.to_json).to_not include("person")
+        expect(JSON.parse(account.to_json)).not_to have_key("account")
       end
     end
 
+    let(:person) do
+      Person.new
+    end
+
     context "when serializing a relation directly" do
 
       context "when serializing an embeds many" do

spec/spec_helper.rb

@@ -31,6 +31,7 @@ def database_id_alt
 
 require 'support/authorization'
 require 'support/expectations'
+require 'support/helpers'
 require 'support/macros'
 require 'support/cluster_config'
 require 'support/constraints'
@@ -156,6 +157,7 @@ class Query
 
 RSpec.configure do |config|
   config.raise_errors_for_deprecations!
+  config.include(Helpers)
   config.include(Mongoid::Expectations)
   config.extend(Constraints)
   config.extend(Mongoid::Macros)

spec/support/helpers.rb

@@ -0,0 +1,11 @@
+module Helpers
+  # Reloads the specified model class.
+  #
+  # @param [ String | Symbol ] name Class name to reload.
+  def reload_model(name)
+    Object.class_eval do
+      remove_const(name)
+    end
+    load "spec/app/models/#{name.to_s.underscore}.rb"
+  end
+end