inequality is a special case of equality

3 files changed, 4 insertions, 10 deletions

diff --git a/lib/arel/algebra/predicates.rb b/lib/arel/algebra/predicates.rb
index e98e152dbd..1b9667ac13 100644
--- a/lib/arel/algebra/predicates.rb
+++ b/lib/arel/algebra/predicates.rb
@@ -109,7 +109,7 @@ module Arel
 
     class Equality < Binary
       def ==(other)
-        Equality === other and
+        self.class === other and
           ((operand1 == other.operand1 and operand2 == other.operand2) or
            (operand1 == other.operand2 and operand2 == other.operand1))
       end
@@ -119,13 +119,7 @@ module Arel
       end
     end
 
-    class Inequality  < Binary
-      def ==(other)
-        Equality === other and
-          ((operand1 == other.operand1 and operand2 == other.operand2) or
-           (operand1 == other.operand2 and operand2 == other.operand1))
-      end
-
+    class Inequality < Equality
       def complement
         Equality.new(operand1, operand2)
       end
diff --git a/lib/arel/engines/memory/predicates.rb b/lib/arel/engines/memory/predicates.rb
index cca6739424..e36afa38c2 100644
--- a/lib/arel/engines/memory/predicates.rb
+++ b/lib/arel/engines/memory/predicates.rb
@@ -52,7 +52,7 @@ module Arel
       def operator; :== end
     end
 
-    class Inequality < Binary
+    class Inequality < Equality
       def eval(row)
         operand1.eval(row) != operand2.eval(row)
       end
diff --git a/lib/arel/engines/sql/predicates.rb b/lib/arel/engines/sql/predicates.rb
index 93d2a2f619..21d8f840c9 100644
--- a/lib/arel/engines/sql/predicates.rb
+++ b/lib/arel/engines/sql/predicates.rb
@@ -52,7 +52,7 @@ module Arel
       end
     end
 
-    class Inequality < Binary
+    class Inequality < Equality
       def predicate_sql
         operand2.inequality_predicate_sql
       end