From 549342aeed2a5e9962c43f14f744930511d86de8 Mon Sep 17 00:00:00 2001
From: Marten Schilstra <mail@martenschilstra.nl>
Date: Wed, 23 Sep 2015 16:03:04 +0200
Subject: [PATCH] Add support for attribute alias.

---
 lib/ransack.rb                                |  7 ++++++
 lib/ransack/adapters/active_record/base.rb    |  6 ++++-
 lib/ransack/nodes/bindable.rb                 | 24 ++++++++++++++-----
 .../adapters/active_record/base_spec.rb       | 12 ++++++++++
 spec/ransack/search_spec.rb                   | 11 +++++++++
 spec/support/schema.rb                        |  7 +++---
 6 files changed, 57 insertions(+), 10 deletions(-)

diff --git a/lib/ransack.rb b/lib/ransack.rb
index 2e28cdc1d..f33732313 100644
--- a/lib/ransack.rb
+++ b/lib/ransack.rb
@@ -8,6 +8,13 @@
 module Ransack
   extend Configuration
   class UntraversableAssociationError < StandardError; end;
+
+  SUPPORTS_ATTRIBUTE_ALIAS =
+  begin
+    ActiveRecord::Base.respond_to?(:attribute_aliases)
+  rescue NameError
+    false
+  end
 end
 
 Ransack.configure do |config|
diff --git a/lib/ransack/adapters/active_record/base.rb b/lib/ransack/adapters/active_record/base.rb
index 66b2b8e55..6d9ef7b31 100644
--- a/lib/ransack/adapters/active_record/base.rb
+++ b/lib/ransack/adapters/active_record/base.rb
@@ -25,7 +25,11 @@ def ransacker(name, opts = {}, &block)
         # For overriding with a whitelist array of strings.
         #
         def ransackable_attributes(auth_object = nil)
-          column_names + _ransackers.keys
+          if Ransack::SUPPORTS_ATTRIBUTE_ALIAS
+            column_names + _ransackers.keys + attribute_aliases.keys
+          else
+            column_names + _ransackers.keys
+          end
         end
 
         # Ransackable_associations, by default, returns the names
diff --git a/lib/ransack/nodes/bindable.rb b/lib/ransack/nodes/bindable.rb
index b80d8aec0..72bb17887 100644
--- a/lib/ransack/nodes/bindable.rb
+++ b/lib/ransack/nodes/bindable.rb
@@ -27,14 +27,26 @@ def reset_binding!
 
       private
 
-        def get_arel_attribute
-          if ransacker
-            ransacker.attr_from(self)
-          else
-            context.table_for(parent)[attr_name]
-          end
+      def get_arel_attribute
+        if ransacker
+          ransacker.attr_from(self)
+        else
+          get_attribute
         end
+      end
 
+      def get_attribute
+        if is_alias_attribute?
+          context.table_for(parent)[context.klass.attribute_aliases[attr_name]]
+        else
+          context.table_for(parent)[attr_name]
+        end
+      end
+
+      def is_alias_attribute?
+        Ransack::SUPPORTS_ATTRIBUTE_ALIAS &&
+        context.klass.attribute_aliases.key?(attr_name)
+      end
     end
   end
 end
diff --git a/spec/ransack/adapters/active_record/base_spec.rb b/spec/ransack/adapters/active_record/base_spec.rb
index 957a66fc9..34cf49246 100644
--- a/spec/ransack/adapters/active_record/base_spec.rb
+++ b/spec/ransack/adapters/active_record/base_spec.rb
@@ -274,6 +274,14 @@ def self.simple_escaping?
             expect(s.result.to_a).to eq [p]
           end
 
+          it "should translate attribute aliased column names",
+          :if => Ransack::SUPPORTS_ATTRIBUTE_ALIAS do
+            s = Person.ransack(:full_name_eq => 'Nicolas Cage')
+            expect(s.result.to_sql).to match(
+              /WHERE #{quote_table_name("people")}.#{quote_column_name("name")}/
+            )
+          end
+
           it 'allows sort by "only_sort" field' do
             s = Person.ransack(
               "s" => { "0" => { "dir" => "asc", "name" => "only_sort" } }
@@ -382,6 +390,10 @@ def self.simple_escaping?
             it { should include 'only_search' }
             it { should_not include 'only_sort' }
             it { should_not include 'only_admin' }
+
+            if Ransack::SUPPORTS_ATTRIBUTE_ALIAS
+              it { should include 'full_name' }
+            end
           end
 
           context 'with auth_object :admin' do
diff --git a/spec/ransack/search_spec.rb b/spec/ransack/search_spec.rb
index 779fba8f6..52d3cf93b 100644
--- a/spec/ransack/search_spec.rb
+++ b/spec/ransack/search_spec.rb
@@ -93,6 +93,17 @@ module Ransack
         expect(condition.value).to eq 'Ernie'
       end
 
+
+      it 'creates conditions for aliased attributes',
+      :if => Ransack::SUPPORTS_ATTRIBUTE_ALIAS do
+        search = Search.new(Person, full_name_eq: 'Ernie')
+        condition = search.base[:full_name_eq]
+        expect(condition).to be_a Nodes::Condition
+        expect(condition.predicate.name).to eq 'eq'
+        expect(condition.attributes.first.name).to eq 'full_name'
+        expect(condition.value).to eq 'Ernie'
+      end
+
       it 'preserves default scope and conditions for associations' do
         search = Search.new(Person, published_articles_title_eq: 'Test')
         expect(search.result.to_sql).to include 'default_scope'
diff --git a/spec/support/schema.rb b/spec/support/schema.rb
index 735b056a6..51caec7db 100644
--- a/spec/support/schema.rb
+++ b/spec/support/schema.rb
@@ -50,6 +50,8 @@ class Person < ActiveRecord::Base
     of_age ? where("age >= ?", 18) : where("age < ?", 18)
   }
 
+  alias_attribute :full_name, :name
+
   ransacker :reversed_name, :formatter => proc { |v| v.reverse } do |parent|
     parent.table[:name]
   end
@@ -89,9 +91,9 @@ class Person < ActiveRecord::Base
 
   def self.ransackable_attributes(auth_object = nil)
     if auth_object == :admin
-      column_names + _ransackers.keys - ['only_sort']
+      super - ['only_sort']
     else
-      column_names + _ransackers.keys - ['only_sort', 'only_admin']
+      super - ['only_sort', 'only_admin']
     end
   end
 
@@ -102,7 +104,6 @@ def self.ransortable_attributes(auth_object = nil)
       column_names + _ransackers.keys - ['only_search', 'only_admin']
     end
   end
-
 end
 
 class Article < ActiveRecord::Base