arel more nicely supports EXISTS queries

1 files changed, 22 insertions, 6 deletions

diff --git a/test/test_select_manager.rb b/test/test_select_manager.rb
index ebec92b1da..d63bec0093 100644
--- a/test/test_select_manager.rb
+++ b/test/test_select_manager.rb
@@ -56,9 +56,7 @@ module Arel
           manager.project SqlLiteral.new '*'
           manager.from table
           manager.order :foo
-          manager.to_sql.must_be_like %{
-          SELECT * FROM "users" ORDER BY foo
-          }
+          manager.to_sql.must_be_like %{ SELECT * FROM "users" ORDER BY foo }
         end
       end
 
@@ -68,9 +66,7 @@ module Arel
           manager = Arel::SelectManager.new Table.engine
           manager.from table
           manager.group :foo
-          manager.to_sql.must_be_like %{
-          SELECT FROM "users" GROUP BY foo
-          }
+          manager.to_sql.must_be_like %{ SELECT FROM "users" GROUP BY foo }
         end
       end
 
@@ -130,6 +126,26 @@ module Arel
       end
     end
 
+    describe 'exists' do
+      it 'should create an exists clause' do
+        table = Table.new(:users)
+        manager = Arel::SelectManager.new Table.engine, table
+        manager.project SqlLiteral.new '*'
+        m2 = Arel::SelectManager.new(manager.engine)
+        m2.project manager.exists
+        m2.to_sql.must_be_like %{ SELECT EXISTS (#{manager.to_sql}) }
+      end
+
+      it 'can be aliased' do
+        table = Table.new(:users)
+        manager = Arel::SelectManager.new Table.engine, table
+        manager.project SqlLiteral.new '*'
+        m2 = Arel::SelectManager.new(manager.engine)
+        m2.project manager.exists.as('foo')
+        m2.to_sql.must_be_like %{ SELECT EXISTS (#{manager.to_sql}) AS foo }
+      end
+    end
+
     describe 'ast' do
       it 'should return the ast' do
         table   = Table.new :users