update manager is working

4 files changed, 28 insertions, 1 deletions

diff --git a/lib/arel/nodes/update_statement.rb b/lib/arel/nodes/update_statement.rb
index 66996f11a3..3df54bb3a9 100644
--- a/lib/arel/nodes/update_statement.rb
+++ b/lib/arel/nodes/update_statement.rb
@@ -1,11 +1,12 @@
 module Arel
   module Nodes
     class UpdateStatement
-      attr_accessor :relation, :wheres
+      attr_accessor :relation, :wheres, :values
 
       def initialize
         @relation = nil
         @wheres   = []
+        @values   = nil
       end
     end
   end
diff --git a/lib/arel/update_manager.rb b/lib/arel/update_manager.rb
index 3af73d2962..cc2f973842 100644
--- a/lib/arel/update_manager.rb
+++ b/lib/arel/update_manager.rb
@@ -16,5 +16,10 @@ module Arel
       @head.wheres << expr
       self
     end
+
+    def set values
+      @head.values = values
+      self
+    end
   end
 end
diff --git a/lib/arel/visitors/to_sql.rb b/lib/arel/visitors/to_sql.rb
index 41d1299948..9a9dd20d52 100644
--- a/lib/arel/visitors/to_sql.rb
+++ b/lib/arel/visitors/to_sql.rb
@@ -15,6 +15,9 @@ module Arel
       def visit_Arel_Nodes_UpdateStatement o
         [
           "UPDATE #{visit o.relation}",
+          ("SET #{o.values.map { |column,value|
+              "#{quote_column_name(column.name)} = #{quote visit value}"
+            }.join ', '}" if o.values),
           ("WHERE #{o.wheres.map { |x| visit x }.join ' AND '}" unless o.wheres.empty?)
         ].compact.join ' '
       end
diff --git a/spec/arel/update_manager_spec.rb b/spec/arel/update_manager_spec.rb
index 9d2346137f..97b497b377 100644
--- a/spec/arel/update_manager_spec.rb
+++ b/spec/arel/update_manager_spec.rb
@@ -8,6 +8,24 @@ module Arel
       end
     end
 
+    describe 'set' do
+      it 'takes a list of lists' do
+        table = Table.new(:users)
+        um = Arel::UpdateManager.new Table.engine
+        um.table table
+        um.set [[table[:id], 1], [table[:name], 'hello']]
+        um.to_sql.should be_like %{
+          UPDATE "users" SET "id" = 1, "name" =  'hello'
+        }
+      end
+
+      it 'chains' do
+        table = Table.new(:users)
+        um = Arel::UpdateManager.new Table.engine
+        um.set([[table[:id], 1], [table[:name], 'hello']]).should == um
+      end
+    end
+
     describe 'table' do
       it 'generates an update statement' do
         um = Arel::UpdateManager.new Table.engine