Keep in #attributes Hash only explicitly specified values in constructor

Author: andrykonchin

lib/dynamoid/document.rb

@@ -138,13 +138,14 @@ def initialize(attrs = {})
         @associations ||= {}
         @attributes_before_type_cast ||= {}
 
-        attrs_with_defaults = {}
-        self.class.attributes.each do |attribute, options|
-          attrs_with_defaults[attribute] = if attrs.key?(attribute)
-                                             attrs[attribute]
-                                           elsif options.key?(:default)
-                                             evaluate_default_value(options[:default])
-                                           end
+        attrs_with_defaults = self.class.attributes.reduce({}) do |res, (attribute, options)|
+          if attrs.key?(attribute)
+            res.merge(attribute => attrs[attribute])
+          elsif options.key?(:default)
+            res.merge(attribute => evaluate_default_value(options[:default]))
+          else
+            res
+          end
         end
 
         attrs_virtual = attrs.slice(*(attrs.keys - self.class.attributes.keys))

spec/dynamoid/before_type_cast_spec.rb

@@ -14,10 +14,7 @@
       obj = klass.new(admin: 0)
 
       expect(obj.attributes_before_type_cast).to eql(
-        id: nil,
         admin: 0,
-        created_at: nil,
-        updated_at: nil
       )
     end
 
@@ -30,12 +27,7 @@
       obj = klass_with_many_fields.new(first_name: 'John')
 
       expect(obj.attributes_before_type_cast).to eql(
-        id: nil,
         first_name: 'John',
-        last_name: nil,
-        email: nil,
-        created_at: nil,
-        updated_at: nil
       )
     end
 
@@ -46,22 +38,14 @@
       obj = klass_with_default_value.new
 
       expect(obj.attributes_before_type_cast).to eql(
-        id: nil,
         activated_on: '2018-09-27',
-        created_at: nil,
-        updated_at: nil
       )
     end
 
     it 'returns nil if field does not have default value' do
       obj = klass.new
 
-      expect(obj.attributes_before_type_cast).to eql(
-        id: nil,
-        admin: nil,
-        created_at: nil,
-        updated_at: nil
-      )
+      expect(obj.attributes_before_type_cast).to eql({})
     end
 
     it 'returns values loaded from the storage before type casting' do
@@ -71,8 +55,6 @@
       expect(obj2.attributes_before_type_cast).to eql(
         id: obj.id,
         admin: false,
-        created_at: nil,
-        updated_at: nil
       )
     end
   end

spec/dynamoid/document_spec.rb

@@ -7,16 +7,7 @@
     address = Address.new
 
     expect(address.new_record).to be_truthy
-    expect(address.attributes).to eq(id: nil,
-                                     created_at: nil,
-                                     updated_at: nil,
-                                     city: nil,
-                                     options: nil,
-                                     deliverable: nil,
-                                     latitude: nil,
-                                     config: nil,
-                                     registered_on: nil,
-                                     lock_version: nil)
+    expect(address.attributes).to eq({})
   end
 
   it 'responds to will_change! methods for all fields' do
@@ -32,33 +23,15 @@
 
     expect(address.new_record).to be_truthy
 
-    expect(address.attributes).to eq(id: nil,
-                                     created_at: nil,
-                                     updated_at: nil,
-                                     city: 'Chicago',
-                                     options: nil,
-                                     deliverable: nil,
-                                     latitude: nil,
-                                     config: nil,
-                                     registered_on: nil,
-                                     lock_version: nil)
+    expect(address.attributes).to eq(city: 'Chicago')
   end
 
   it 'initializes a new document with a virtual attribute' do
     address = Address.new(zip_code: '12345')
 
     expect(address.new_record).to be_truthy
 
-    expect(address.attributes).to eq(id: nil,
-                                     created_at: nil,
-                                     updated_at: nil,
-                                     city: 'Chicago',
-                                     options: nil,
-                                     deliverable: nil,
-                                     latitude: nil,
-                                     config: nil,
-                                     registered_on: nil,
-                                     lock_version: nil)
+    expect(address.attributes).to eq(city: 'Chicago')
   end
 
   it 'allows interception of write_attribute on load' do