1 files changed, 33 insertions, 4 deletions
diff --git a/activerecord/lib/active_record/migration.rb b/activerecord/lib/active_record/migration.rb
index 2a9139749d..c1d57855a9 100644
--- a/activerecord/lib/active_record/migration.rb
+++ b/activerecord/lib/active_record/migration.rb
@@ -1,7 +1,4 @@
-require "active_support/core_ext/module/delegation"
 require "active_support/core_ext/class/attribute_accessors"
-require 'active_support/deprecation'
-require 'active_record/schema_migration'
 require 'set'
 
 module ActiveRecord
@@ -33,6 +30,12 @@ module ActiveRecord
     end
   end
 
+  class PendingMigrationError < ActiveRecordError#:nodoc:
+    def initialize
+      super("Migrations are pending run 'rake db:migrate RAILS_ENV=#{ENV['RAILS_ENV']}' to resolve the issue")
+    end
+  end
+
   # = Active Record Migrations
   #
   # Migrations can manage the evolution of a schema used by several physical
@@ -47,7 +50,7 @@ module ActiveRecord
   #
   #   class AddSsl < ActiveRecord::Migration
   #     def up
-  #       add_column :accounts, :ssl_enabled, :boolean, :default => 1
+  #       add_column :accounts, :ssl_enabled, :boolean, :default => true
   #     end
   #
   #     def down
@@ -327,10 +330,28 @@ module ActiveRecord
   class Migration
     autoload :CommandRecorder, 'active_record/migration/command_recorder'
 
+
+    # This class is used to verify that all migrations have been run before
+    # loading a web page if config.active_record.migration_error is set to :page_load
+    class CheckPending
+      def initialize(app)
+        @app = app
+      end
+
+      def call(env)
+        ActiveRecord::Migration.check_pending!
+        @app.call(env)
+      end
+    end
+
     class << self
       attr_accessor :delegate # :nodoc:
     end
 
+    def self.check_pending!
+      raise ActiveRecord::PendingMigrationError if ActiveRecord::Migrator.needs_migration?
+    end
+
     def self.method_missing(name, *args, &block) # :nodoc:
       (delegate || superclass.delegate).send(name, *args, &block)
     end
@@ -606,6 +627,14 @@ module ActiveRecord
         end
       end
 
+      def needs_migration?
+        current_version < last_version
+      end
+
+      def last_version
+        migrations(migrations_paths).last.try(:version)||0
+      end
+
       def proper_table_name(name)
         # Use the Active Record objects own table_name, or pre/suffix from ActiveRecord::Base if name is a symbol/string
         name.table_name rescue "#{ActiveRecord::Base.table_name_prefix}#{name}#{ActiveRecord::Base.table_name_suffix}"