Prefer .dynamoid_dump over #dynamoid_dump for custom type field

Author: andrykonchin

lib/dynamoid/dumping.rb

@@ -323,10 +323,10 @@ class CustomTypeDumper < Base
       def process(value)
         field_class = @options[:type]
 
-        if value.respond_to?(:dynamoid_dump)
-          value.dynamoid_dump
-        elsif field_class.respond_to?(:dynamoid_dump)
+        if field_class.respond_to?(:dynamoid_dump)
           field_class.dynamoid_dump(value)
+        elsif value.respond_to?(:dynamoid_dump)
+          value.dynamoid_dump
         else
           raise ArgumentError, "Neither #{field_class} nor #{value} supports serialization for Dynamoid."
         end

spec/dynamoid/dumping_spec.rb

@@ -1449,6 +1449,21 @@ def self.load(str)
       end
     end
 
+    context 'Custom type with adapter interface provided' do
+      let(:klass) do
+        new_class do |_options|
+          field :user, DumpingSpecs::UserWithAdapterInterface
+        end
+      end
+
+      it "prefers adapter's .dynamoid_dump method over #dynamoid_dump" do
+        user = DumpingSpecs::UserWithAdapterInterface.new('John')
+        obj = klass.create(user: user)
+
+        expect(raw_attributes(obj)[:user]).to eql('John (dumped with .dynamoid_dump)')
+      end
+    end
+
     context 'DynamoDB type specified' do
       let(:klass) do
         new_class do

spec/fixtures/dumping.rb

@@ -25,6 +25,35 @@ def self.dynamoid_load(string)
     end
   end
 
+  # implements both #dynamoid_dump and .dynamoid_dump methods
+  class UserWithAdapterInterface
+    attr_accessor :name
+
+    def initialize(name)
+      self.name = name
+    end
+
+    def dynamoid_dump
+      name + ' (dumped with #dynamoid_dump)'
+    end
+
+    def eql?(other)
+      name == other.name
+    end
+
+    def hash
+      name.hash
+    end
+
+    def self.dynamoid_dump(user)
+      user.name + ' (dumped with .dynamoid_dump)'
+    end
+
+    def self.dynamoid_load(string)
+      new(string.to_s)
+    end
+  end
+
   # doesn't implement #dynamoid_dump/#dynamoid_load methods so requires an adapter
   class UserValue
     attr_accessor :name