Merge pull request #6800 from mschneider/dynamic_finders_for_aliased_attributes

Dynamic finders for aliased attributes

activemodel/lib/active_model/attribute_methods.rb

@@ -61,7 +61,8 @@ module ActiveModel
     CALL_COMPILABLE_REGEXP = /\A[a-zA-Z_]\w*[!?]?\z/
 
     included do
-      class_attribute :attribute_method_matchers, instance_writer: false
+      class_attribute :attribute_aliases, :attribute_method_matchers, instance_writer: false
+      self.attribute_aliases = {}
       self.attribute_method_matchers = [ClassMethods::AttributeMethodMatcher.new]
     end
 
@@ -192,6 +193,7 @@ module ActiveModel
       #   person.nickname # => "Bob"
       #   person.name     # => "Bob"
       def alias_attribute(new_name, old_name)
+        self.attribute_aliases = attribute_aliases.merge(new_name.to_s => old_name.to_s)
         attribute_method_matchers.each do |matcher|
           matcher_new = matcher.method_name(new_name).to_s
           matcher_old = matcher.method_name(old_name).to_s

activemodel/test/cases/attribute_methods_test.rb

@@ -154,6 +154,15 @@ class AttributeMethodsTest < ActiveModel::TestCase
     assert_equal "value of foo", ModelWithAttributes.new.foo
   end
 
+  test '#alias_attribute generates attribute_aliases lookup hash' do
+    klass = Class.new(ModelWithAttributes) do
+      define_attribute_methods :foo
+      alias_attribute :bar, :foo
+    end
+
+    assert_equal({ "bar" => "foo" }, klass.attribute_aliases)
+  end
+
   test '#define_attribute_methods generates attribute methods with spaces in their names' do
     ModelWithAttributesWithSpaces.define_attribute_methods(:'foo bar')
 

activerecord/lib/active_record/dynamic_matchers.rb

@@ -53,6 +53,7 @@ module ActiveRecord
         @model           = model
         @name            = name.to_s
         @attribute_names = @name.match(self.class.pattern)[1].split('_and_')
+        @attribute_names.map! { |n| @model.attribute_aliases[n] || n }
       end
 
       def valid?

activerecord/test/cases/deprecated_dynamic_methods_test.rb

@@ -524,7 +524,8 @@ class DynamicScopeMatchTest < ActiveRecord::TestCase
   end
 
   def test_scoped_by
-    match = ActiveRecord::DynamicMatchers::Method.match(nil, "scoped_by_age_and_sex_and_location")
+    model = stub(attribute_aliases: {})
+    match = ActiveRecord::DynamicMatchers::Method.match(model, "scoped_by_age_and_sex_and_location")
     assert_not_nil match
     assert_equal %w(age sex location), match.attribute_names
   end

activerecord/test/cases/finder_respond_to_test.rb

@@ -36,6 +36,11 @@ class FinderRespondToTest < ActiveRecord::TestCase
     assert_respond_to Topic, :find_by_title_and_author_name
   end
 
+  def test_should_respond_to_find_all_by_an_aliased_attribute
+    ensure_topic_method_is_not_cached(:find_by_heading)
+    assert_respond_to Topic, :find_by_heading
+  end
+
   def test_should_respond_to_find_or_initialize_from_one_attribute
     ensure_topic_method_is_not_cached(:find_or_initialize_by_title)
     assert_respond_to Topic, :find_or_initialize_by_title

activerecord/test/cases/finder_test.rb

@@ -535,6 +535,11 @@ class FinderTest < ActiveRecord::TestCase
     assert_raise(ActiveRecord::RecordNotFound) { Topic.find_by_title!("The First Topic!") }
   end
 
+  def test_find_by_one_attribute_that_is_an_alias
+    assert_equal topics(:first), Topic.find_by_heading("The First Topic")
+    assert_nil Topic.find_by_heading("The First Topic!")
+  end
+
   def test_find_by_one_attribute_with_conditions
     assert_equal accounts(:rails_core_account), Account.where('firm_id = ?', 6).find_by_credit_limit(50)
   end

activerecord/test/models/topic.rb

@@ -58,6 +58,8 @@ class Topic < ActiveRecord::Base
     id
   end
 
+  alias_attribute :heading, :title
+
   before_validation :before_validation_for_transaction
   before_save :before_save_for_transaction
   before_destroy :before_destroy_for_transaction