performance enhancements

17 files changed, 58 insertions, 58 deletions

diff --git a/lib/arel/predicates.rb b/lib/arel/predicates.rb
index b375f37ff4..f21376d4c9 100644
--- a/lib/arel/predicates.rb
+++ b/lib/arel/predicates.rb
@@ -1,8 +1,5 @@
 module Arel
   class Predicate
-    def ==(other)
-      self.class == other.class
-    end
   end
 
   class Binary < Predicate
@@ -13,7 +10,9 @@ module Arel
     end
 
     def ==(other)
-      super and @operand1 == other.operand1 and @operand2 == other.operand2
+      self.class === other          and
+      @operand1  ==  other.operand1 and
+      @operand2  ==  other.operand2
     end
     
     def bind(relation)
@@ -28,7 +27,7 @@ module Arel
 
   class Equality < Binary
     def ==(other)
-      Equality == other.class and
+      Equality === other and
         ((operand1 == other.operand1 and operand2 == other.operand2) or
          (operand1 == other.operand2 and operand2 == other.operand1))
     end
diff --git a/lib/arel/primitives/attribute.rb b/lib/arel/primitives/attribute.rb
index 011b751a1d..ca1d31ffcf 100644
--- a/lib/arel/primitives/attribute.rb
+++ b/lib/arel/primitives/attribute.rb
@@ -30,11 +30,11 @@ module Arel
     end
     
     def ==(other)
-      Attribute   == other.class     and
-      name        == other.name      and
-      @alias      == other.alias     and
-      ancestor    == other.ancestor  and
-      relation    == other.relation
+      Attribute   === other           and
+      name        ==  other.name      and
+      @alias      ==  other.alias     and
+      ancestor    ==  other.ancestor  and
+      relation    ==  other.relation
     end
 
     def original_relation
diff --git a/lib/arel/primitives/expression.rb b/lib/arel/primitives/expression.rb
index 696e3521be..9afafcce2f 100644
--- a/lib/arel/primitives/expression.rb
+++ b/lib/arel/primitives/expression.rb
@@ -17,11 +17,11 @@ module Arel
     end
     
     def ==(other)
-      Expression    == other.class          and
-      attribute     == other.attribute      and
-      function_sql  == other.function_sql   and
-      ancestor      == other.ancestor       and
-      @alias        == other.alias
+      Expression    === other                and
+      attribute     ==  other.attribute      and
+      function_sql  ==  other.function_sql   and
+      ancestor      ==  other.ancestor       and
+      @alias        ==  other.alias
     end
     
     module Transformations
diff --git a/lib/arel/primitives/value.rb b/lib/arel/primitives/value.rb
index b4bddd0b0c..4509f13d17 100644
--- a/lib/arel/primitives/value.rb
+++ b/lib/arel/primitives/value.rb
@@ -17,8 +17,8 @@ module Arel
     end
     
     def ==(other)
-      Value == other.class and
-      value == other.value
+      Value === other and
+      value ==  other.value
     end
     
     def bind(relation)
diff --git a/lib/arel/relations/aggregation.rb b/lib/arel/relations/aggregation.rb
index a6f40be786..9a34ea5d89 100644
--- a/lib/arel/relations/aggregation.rb
+++ b/lib/arel/relations/aggregation.rb
@@ -19,8 +19,8 @@ module Arel
     end
     
     def ==(other)
-      Aggregation   == other.class and
-      self.relation == other.relation
+      Aggregation   === other and
+      self.relation ==  other.relation
     end
   end
   
diff --git a/lib/arel/relations/deletion.rb b/lib/arel/relations/deletion.rb
index 8c9d873a02..cd58771846 100644
--- a/lib/arel/relations/deletion.rb
+++ b/lib/arel/relations/deletion.rb
@@ -18,8 +18,8 @@ module Arel
     end
     
     def ==(other)
-      Deletion    == other.class    and
-      relation    == other.relation
+      Deletion    === other and
+      relation    ==  other.relation
     end
   end
 end
\ No newline at end of file
diff --git a/lib/arel/relations/grouping.rb b/lib/arel/relations/grouping.rb
index 39b5942bcc..6d11299051 100644
--- a/lib/arel/relations/grouping.rb
+++ b/lib/arel/relations/grouping.rb
@@ -7,9 +7,9 @@ module Arel
     end
 
     def ==(other)
-      Grouping    == other.class      and
-      relation    == other.relation   and
-      groupings   == other.groupings
+      Grouping    === other          and
+      relation    ==  other.relation and
+      groupings   ==  other.groupings
     end
 
     def aggregation?
diff --git a/lib/arel/relations/insertion.rb b/lib/arel/relations/insertion.rb
index cc7fcb4fb0..16eb9b7555 100644
--- a/lib/arel/relations/insertion.rb
+++ b/lib/arel/relations/insertion.rb
@@ -20,7 +20,7 @@ module Arel
     end
     
     def ==(other)
-      Insertion   == other.class    and
+      Insertion   === other         and
       relation    == other.relation and
       record      == other.record
     end
diff --git a/lib/arel/relations/join.rb b/lib/arel/relations/join.rb
index 9cc9f95c81..81a157dc10 100644
--- a/lib/arel/relations/join.rb
+++ b/lib/arel/relations/join.rb
@@ -13,13 +13,15 @@ module Arel
     end
     
     def joins(environment, formatter = Sql::TableReference.new(environment))
-      this_join = [
-        join_sql,
-        relation2.externalize.table_sql(formatter),
-        ("ON" unless predicates.blank?),
-        (ons + relation2.externalize.selects).collect { |p| p.bind(environment).to_sql(Sql::WhereClause.new(environment)) }.join(' AND ')
-      ].compact.join(" ")
-      [relation1.joins(environment), this_join, relation2.joins(environment)].compact.join(" ")
+      @joins ||= begin
+        this_join = [
+          join_sql,
+          relation2.externalize.table_sql(formatter),
+          ("ON" unless predicates.blank?),
+          (ons + relation2.externalize.selects).collect { |p| p.bind(environment).to_sql(Sql::WhereClause.new(environment)) }.join(' AND ')
+        ].compact.join(" ")
+        [relation1.joins(environment), this_join, relation2.joins(environment)].compact.join(" ")
+      end
     end
 
     def attributes
@@ -45,11 +47,10 @@ module Arel
     end
     
     def ==(other)
-      Join       == other.class       and
-      predicates == other.predicates  and (
-        (relation1 == other.relation1 and relation2 == other.relation2) or
-        (relation2 == other.relation1 and relation1 == other.relation2)
-      )
+      Join       === other             and
+      predicates ==  other.predicates  and
+      relation1  ==  other.relation1   and
+      relation2  ==  other.relation2
     end
   end
   
diff --git a/lib/arel/relations/nil.rb b/lib/arel/relations/nil.rb
index c34fe71473..2dcfb47233 100644
--- a/lib/arel/relations/nil.rb
+++ b/lib/arel/relations/nil.rb
@@ -4,7 +4,7 @@ module Arel
     def name; '' end
 
     def ==(other)
-      Nil == other.class
+      Nil === other
     end
   end
 end
\ No newline at end of file
diff --git a/lib/arel/relations/order.rb b/lib/arel/relations/order.rb
index 31032e871c..ebb4dc0668 100644
--- a/lib/arel/relations/order.rb
+++ b/lib/arel/relations/order.rb
@@ -11,9 +11,9 @@ module Arel
     end
     
     def ==(other)
-      Order       == other.class    and
-      relation    == other.relation and
-      orderings   == other.orderings
+      Order       === other          and
+      relation    ==  other.relation and
+      orderings   ==  other.orderings
     end
   end
 end
\ No newline at end of file
diff --git a/lib/arel/relations/projection.rb b/lib/arel/relations/projection.rb
index 7eea63d808..d74f111271 100644
--- a/lib/arel/relations/projection.rb
+++ b/lib/arel/relations/projection.rb
@@ -15,9 +15,9 @@ module Arel
     end
     
     def ==(other)
-      Projection  == other.class    and
-      relation    == other.relation and
-      projections == other.projections
+      Projection  === other          and
+      relation    ==  other.relation and
+      projections ==  other.projections
     end
   end
 end
\ No newline at end of file
diff --git a/lib/arel/relations/selection.rb b/lib/arel/relations/selection.rb
index 0c5956d2fc..fc4e94621a 100644
--- a/lib/arel/relations/selection.rb
+++ b/lib/arel/relations/selection.rb
@@ -13,9 +13,9 @@ module Arel
     end    
 
     def ==(other)
-      Selection  == other.class and
-      relation   == other.relation and
-      predicate  == other.predicate
+      Selection  === other          and
+      relation   ==  other.relation and
+      predicate  ==  other.predicate
     end
   end
 end
\ No newline at end of file
diff --git a/lib/arel/relations/skip.rb b/lib/arel/relations/skip.rb
index 4686e03177..01ac4c7204 100644
--- a/lib/arel/relations/skip.rb
+++ b/lib/arel/relations/skip.rb
@@ -7,9 +7,9 @@ module Arel
     end
 
     def ==(other)
-      Skip        == other.class    and
-      relation    == other.relation and
-      skipped     == other.skipped
+      Skip        === other          and
+      relation    ==  other.relation and
+      skipped     ==  other.skipped
     end
   end
 end
\ No newline at end of file
diff --git a/lib/arel/relations/table.rb b/lib/arel/relations/table.rb
index 06625dd52a..087028fb55 100644
--- a/lib/arel/relations/table.rb
+++ b/lib/arel/relations/table.rb
@@ -29,8 +29,8 @@ module Arel
     end
     
     def ==(other)
-      Table      == other.class and
-      name       == other.name
+      Table      === other and
+      name       ==  other.name
     end
   end
 end
\ No newline at end of file
diff --git a/lib/arel/relations/take.rb b/lib/arel/relations/take.rb
index 80aa62a878..0a49891aee 100644
--- a/lib/arel/relations/take.rb
+++ b/lib/arel/relations/take.rb
@@ -7,9 +7,9 @@ module Arel
     end
 
     def ==(other)
-      Take        == other.class    and
-      relation    == other.relation and
-      taken       == other.taken
+      Take        === other          and
+      relation    ==  other.relation and
+      taken       ==  other.taken
     end
   end
 end
\ No newline at end of file
diff --git a/lib/arel/relations/update.rb b/lib/arel/relations/update.rb
index 486ad2ab12..8306a83aac 100644
--- a/lib/arel/relations/update.rb
+++ b/lib/arel/relations/update.rb
@@ -22,9 +22,9 @@ module Arel
     end
     
     def ==(other)
-      Update      == other.class    and
-      relation    == other.relation and
-      assignments == other.assignments
+      Update      === other          and
+      relation    ==  other.relation and
+      assignments ==  other.assignments
     end
   end
 end
\ No newline at end of file