Add values_at attribute method for active_record

activerecord/CHANGELOG.md

@@ -1,3 +1,17 @@
+*   Add `values_at` method.
+
+    Returns an array containing the values associated with the given methods.
+
+    ```ruby
+    topic = Topic.first
+    topic.values_at(:title, :author_name)
+    # => ["Budget", "Jason"]
+    ```
+
+    Similar to `Hash#values_at` but on an Active Record instance.
+
+    *Guillaume Briday*
+
 *   Fix `read_attribute_before_type_cast` to consider attribute aliases.
 
     *Marcelo Lauxen*

activerecord/lib/active_record/core.rb

@@ -601,6 +601,11 @@ module ActiveRecord
       Hash[methods.flatten.map! { |method| [method, public_send(method)] }].with_indifferent_access
     end
 
+    # Returns an array of the values returned by the given methods.
+    def values_at(*methods)
+      methods.flatten.map! { |method| public_send(method) }
+    end
+
     private
       # +Array#flatten+ will call +#to_ary+ (recursively) on each of the elements of
       # the array, and then rescues from the possible +NoMethodError+. If those elements are

activerecord/test/cases/base_test.rb

@@ -1411,6 +1411,21 @@ class BasicsTest < ActiveRecord::TestCase
     assert_equal attrs, topic.slice(attrs.keys)
   end
 
+  def test_values_at
+    company = Company.new(name: "37signals", rating: 1)
+
+    assert_equal [ "37signals", 1, "I am Jack's profound disappointment" ],
+      company.values_at(:name, :rating, :arbitrary_method)
+    assert_equal [ "I am Jack's profound disappointment", 1, "37signals" ],
+      company.values_at(:arbitrary_method, :rating, :name)
+  end
+
+  def test_values_at_accepts_array_argument
+    topic = Topic.new(title: "Budget", author_name: "Jason")
+
+    assert_equal %w( Budget Jason ), topic.values_at(%w( title author_name ))
+  end
+
   def test_default_values_are_deeply_dupped
     company = Company.new
     company.description << "foo"