Merge pull request rails#289 from mekishizufu/fix_with_statements

Fix WITH statements

lib/arel/visitors/to_sql.rb

@@ -298,8 +298,9 @@ def visit_Arel_Nodes_DistinctOn o, collector
         raise NotImplementedError, 'DISTINCT ON not implemented for this db'
       end
 
-      def visit_Arel_Nodes_With o
-        "WITH #{o.children.map { |x| visit x }.join(', ')}"
+      def visit_Arel_Nodes_With o, collector
+        collector << "WITH "
+        inject_join o.children, collector, ', '
       end
 
       def visit_Arel_Nodes_WithRecursive o, collector

test/test_select_manager.rb

@@ -330,6 +330,20 @@ def test_manager_stores_bind_values
     end
 
     describe 'with' do
+      it 'should support basic WITH' do
+        users          = Table.new(:users)
+        users_top      = Table.new(:users_top)
+        comments       = Table.new(:comments)
+
+        top            = users.project(users[:id]).where(users[:karma].gt(100))
+        users_as       = Arel::Nodes::As.new(users_top, top)
+        select_manager = comments.project(Arel.star).with(users_as)
+                          .where(comments[:author_id].in(users_top.project(users_top[:id])))
+
+        select_manager.to_sql.must_be_like %{
+          WITH "users_top" AS (SELECT "users"."id" FROM "users" WHERE "users"."karma" > 100) SELECT * FROM "comments" WHERE "comments"."author_id" IN (SELECT "users_top"."id" FROM "users_top")
+        }
+      end
 
       it "should support WITH RECURSIVE" do
         comments           = Table.new(:comments)