MONGOID-4737 Deprecate the :compact option on Document#as_json (#5040)

* MONGOID-4737 Deprecate the :compact option on Document#as_json

* Update document_spec.rb

* Explicitly specify warning to not receive

Co-authored-by: shields <shields@tablecheck.com>

Author: johnnyshields

lib/mongoid/document.rb

@@ -173,13 +173,14 @@ def as_document
     #
     # @param [ Hash ] options The options.
     #
-    # @option options [ true, false ] :compact Whether to include fields with
-    #   nil values in the json document.
+    # @option options [ true, false ] :compact (Deprecated) Whether to include fields
+    #   with nil values in the json document.
     #
     # @return [ Hash ] The document as json.
     def as_json(options = nil)
       rv = super
       if options && options[:compact]
+        Mongoid.logger.warn('#as_json :compact option is deprecated. Please call #compact on the returned Hash object instead.')
         rv = rv.compact
       end
       rv

lib/mongoid/tasks/database.rb

@@ -118,7 +118,7 @@ def shard_collections(models = ::Mongoid.models)
           next if model.shard_config.nil?
 
           if model.embedded? && !model.cyclic?
-            logger.warn("MONGOID: #{model} has shard config but is emdedded")
+            logger.warn("MONGOID: #{model} has shard config but is embedded")
             next
           end
 

spec/mongoid/document_spec.rb

@@ -500,7 +500,7 @@ class << self; attr_accessor :name; end
       end
     end
 
-    context ':compact option' do
+    context 'deprecated :compact option' do
       # Since rails 6 differs in how it treats id fields,
       # run this test on one version of rails. Currently rails 6 is in beta,
       # when it is released this version should be changed to 6.
@@ -512,6 +512,26 @@ class << self; attr_accessor :name; end
         expect(church.as_json.keys.sort).to eq(%w(_id location name))
       end
 
+      context 'deprecation' do
+        let(:church) do
+          Church.create!(name: 'St. Basil')
+        end
+
+        let(:message) do
+          '#as_json :compact option is deprecated. Please call #compact on the returned Hash object instead.'
+        end
+
+        it 'logs a deprecation warning when :compact is given' do
+          expect_any_instance_of(Logger).to receive(:warn).with(message)
+          church.as_json(compact: true)
+        end
+
+        it 'does not log a deprecation warning when :compact is not given' do
+          expect_any_instance_of(Logger).to_not receive(:warn).with(message)
+          church.as_json
+        end
+      end
+
       context 'there is a nil valued attribute' do
         let(:church) do
           Church.create!(name: 'St. Basil')