[ci skip] better docs for ActiveRecord::AttributeSet::YAMLEncoder#decode

1 files changed, 17 insertions, 0 deletions

diff --git a/activerecord/lib/active_record/attribute_set/yaml_encoder.rb b/activerecord/lib/active_record/attribute_set/yaml_encoder.rb
index 6208048231..fd063555ec 100644
--- a/activerecord/lib/active_record/attribute_set/yaml_encoder.rb
+++ b/activerecord/lib/active_record/attribute_set/yaml_encoder.rb
@@ -7,6 +7,11 @@ module ActiveRecord
         @default_types = default_types
       end
 
+      # Populate +coder+ with 'concise_attributes' using +attribute_set+.
+      #
+      # If any attribute's name matches a +default_types+ key, then the
+      # attribute will be cast by passing +nil+ to
+      # ActiveRecord::Attribute#with_type.
       def encode(attribute_set, coder)
         coder['concise_attributes'] = attribute_set.each_value.map do |attr|
           if attr.type.equal?(default_types[attr.name])
@@ -17,6 +22,18 @@ module ActiveRecord
         end
       end
 
+      # Decode a previously encoded +coder+.
+      #
+      # +coder+ should be the result of previously encoding an Active Record
+      # model, using #encode.
+      #
+      # If +coder+ contains an 'attributes' key, then #decode returns the value
+      # under the 'attributes' key.
+      #
+      # Otherwise, #decode will build an attributes hash from the provided coder,
+      # using its value under 'concise_attributes', while casting any nil types
+      # using default_types. The resulting hash is used to return a new
+      # ActiveRecord::AttributeSet.
       def decode(coder)
         if coder['attributes']
           coder['attributes']