1 files changed, 9 insertions, 3 deletions
diff --git a/activerecord/lib/active_record/type/float.rb b/activerecord/lib/active_record/type/float.rb
index 42eb44b9a9..d88482b85d 100644
--- a/activerecord/lib/active_record/type/float.rb
+++ b/activerecord/lib/active_record/type/float.rb
@@ -1,18 +1,24 @@
 module ActiveRecord
   module Type
     class Float < Value # :nodoc:
-      include Numeric
+      include Helpers::Numeric
 
       def type
         :float
       end
 
-      alias type_cast_for_database type_cast
+      alias serialize cast
 
       private
 
       def cast_value(value)
-        value.to_f
+        case value
+        when ::Float then value
+        when "Infinity" then ::Float::INFINITY
+        when "-Infinity" then -::Float::INFINITY
+        when "NaN" then ::Float::NAN
+        else value.to_f
+        end
       end
     end
   end