Add attributes_with_aliases and attribute_names_with_aliases

activemodel/lib/active_model/attributes.rb

@@ -75,6 +75,16 @@ def attribute_names
         attribute_types.keys
       end
 
+      def attribute_names_with_aliases(replace: false)
+        attrs = attribute_names.map(&:clone)
+        attribute_aliases.each do |k, v|
+          next unless (i = attrs.find_index(v))
+
+          attrs[replace ? i : attrs.length] = k
+        end
+        attrs
+      end
+
       private
         def define_method_attribute=(name, owner:)
           ActiveModel::AttributeMethods::AttrNames.define_attribute_accessor_method(
@@ -134,6 +144,18 @@ def attribute_names
       @attributes.keys
     end
 
+    def attributes_with_aliases(replace: false)
+      attrs = attributes.clone
+      attribute_aliases.each do |k, v|
+        attrs[k] = replace ? attrs.delete(v) : send(v)
+      end
+      attrs
+    end
+
+    def attribute_names_with_aliases(replace: false)
+      attributes_with_aliases(replace: replace).keys
+    end
+
     def freeze # :nodoc:
       @attributes = @attributes.clone.freeze unless frozen?
       super

activemodel/test/cases/attributes_test.rb

@@ -41,6 +41,10 @@ def attribute=(_, _)
       end
     end
 
+    class ModelWithAliasAttribute < ModelWithGeneratedAttributeMethods
+      alias_attribute :alias_foo, :foo
+    end
+
     test "models that proxy attributes do not conflict with models with generated methods" do
       ModelWithGeneratedAttributeMethods.new
 
@@ -175,5 +179,36 @@ def attribute=(_, _)
         ModelForAttributesTest.attribute :foo, :unknown
       end
     end
+
+    test "reading attributes with aliases" do
+      model = ModelWithAliasAttribute.new
+      model.foo = "foo"
+      expected_attributes = { "foo" => "foo", "alias_foo" => "foo" }
+      assert_equal expected_attributes, model.attributes_with_aliases
+    end
+
+    test "reading attributes replaced by aliases" do
+      model = ModelWithAliasAttribute.new
+      model.foo = "foo"
+      expected_attributes = { "alias_foo" => "foo" }
+      assert_equal expected_attributes, model.attributes_with_aliases(replace: true)
+    end
+
+    test "reading attribute names with aliases" do
+      names = [
+        "foo",
+        "alias_foo"
+      ]
+      assert_equal names, ModelWithAliasAttribute.attribute_names_with_aliases
+      assert_equal names, ModelWithAliasAttribute.new.attribute_names_with_aliases
+    end
+
+    test "reading attribute names replaced by aliases" do
+      names = [
+        "alias_foo"
+      ]
+      assert_equal names, ModelWithAliasAttribute.attribute_names_with_aliases(replace: true)
+      assert_equal names, ModelWithAliasAttribute.new.attribute_names_with_aliases(replace: true)
+    end
   end
 end

activerecord/lib/active_record/attribute_methods.rb

@@ -163,6 +163,16 @@ def attribute_names
         end.freeze
       end
 
+      def attribute_names_with_aliases(replace: false)
+        attrs = attribute_names.map(&:clone)
+        attribute_aliases.each do |k, v|
+          next unless (i = attrs.find_index(v))
+
+          attrs[replace ? i : attrs.length] = k
+        end
+        attrs
+      end
+
       # Returns true if the given attribute exists, otherwise false.
       #
       #   class Person < ActiveRecord::Base
@@ -270,6 +280,18 @@ def attributes
       @attributes.to_hash
     end
 
+    def attributes_with_aliases(replace: false)
+      attrs = attributes.clone
+      attribute_aliases.each do |k, v|
+        attrs[k] = replace ? attrs.delete(v) : send(v)
+      end
+      attrs
+    end
+
+    def attribute_names_with_aliases(replace: false)
+      attributes_with_aliases(replace: replace).keys
+    end
+
     # Returns an <tt>#inspect</tt>-like string for the value of the
     # attribute +attr_name+. String attributes are truncated up to 50
     # characters. Other attributes return the value of <tt>#inspect</tt>

activerecord/test/cases/attribute_methods_test.rb

@@ -1130,6 +1130,32 @@ def some_method_that_is_not_on_super
     assert_equal "abcd", model.read_attribute_before_type_cast("new_bank_balance")
   end
 
+  test "reading attributes with aliases" do
+    topic = Topic.new(title: "Hello")
+    expected_attributes = topic.attributes.merge("heading" => "Hello")
+    assert_equal expected_attributes, topic.attributes_with_aliases
+  end
+
+  test "reading attributes replaced by aliases" do
+    topic = Topic.new(title: "Hello")
+    expected_attributes = topic.attributes.except("title").merge("heading" => "Hello")
+    assert_equal expected_attributes, topic.attributes_with_aliases(replace: true)
+  end
+
+  test "reading attribute names with aliases" do
+    model = @target.new
+    expected_names = @target.column_names + @target.attribute_aliases.keys
+    assert_equal expected_names, @target.attribute_names_with_aliases
+    assert_equal expected_names, model.attribute_names_with_aliases
+  end
+
+  test "reading attribute names replaced by aliases" do
+    model = @target.new
+    expected_names = @target.column_names - @target.attribute_aliases.values + @target.attribute_aliases.keys
+    assert_equal expected_names, @target.attribute_names_with_aliases(replace: true)
+    assert_equal expected_names, model.attribute_names_with_aliases(replace: true)
+  end
+
   private
     def new_topic_like_ar_class(&block)
       klass = Class.new(ActiveRecord::Base) do