Use ampersand literal in limit offset sub to fix FIRST 1/SKIP 1

Author: rzane

lib/arel/visitors/firebird.rb

@@ -13,7 +13,7 @@ def visit_Arel_Nodes_SelectStatement o, a = nil
         sql = o.cores.map { |x| do_visit_select_core x, a }.join
         sql << " ORDER BY #{o.orders.map { |x| do_visit x, a }.join(', ')}" unless o.orders.empty?
 
-        sql.sub!(/\A(\s*SELECT\s)/i, "\&#{lim_off} ") unless lim_off.empty?
+        sql.sub!(/\A(\s*SELECT\s)/i, '\&' + lim_off + ' ') unless lim_off.empty?
         sql
       end
 

test/db/firebird.rb

@@ -14,6 +14,6 @@
 config = { :adapter => 'firebird' }
 config[:username] = ENV['FB_USER'] || 'sysdba'
 config[:password] = ENV['FB_PASS'] || 'masterkey'
-config[:database] = ENV['FB_DATABASE'] || './test.fbd'
+config[:database] = ENV['FB_DATABASE'] || './test.fdb'
 
 ActiveRecord::Base.establish_connection(config)