delete SequelizeMeta database entry after undoing a migration

lib/migrator.js

@@ -36,9 +36,12 @@ module.exports = (function() {
           emitter.emit('failure', err)
           emitter.emit('failure', err)
         } else {
         } else {
           var chainer = new Utils.QueryChainer
           var chainer = new Utils.QueryChainer
+            , from    = migrations[0]
 
 
-          if(options.method == 'down')
+          if(options.method == 'down') {
             migrations.reverse()
             migrations.reverse()
+            from = migrations[0]
+          }
 
 
           migrations.forEach(function(migration) {
           migrations.forEach(function(migration) {
             chainer.add(migration, 'execute', [options], {
             chainer.add(migration, 'execute', [options], {
@@ -51,7 +54,10 @@ module.exports = (function() {
                   console.log('Executed migration: ' + migration.filename)
                   console.log('Executed migration: ' + migration.filename)
               },
               },
               success: function(migration, callback) {
               success: function(migration, callback) {
-                saveSuccessfulMigration.call(self, migrations[0], migration, callback)
+                if(options.method == 'down')
+                  deleteUndoneMigration.call(self, from, migration, callback)
+                else
+                  saveSuccessfulMigration.call(self, from, migration, callback)
               }
               }
             })
             })
           })
           })
@@ -195,5 +201,17 @@ module.exports = (function() {
     })
     })
   }
   }
 
 
+  var deleteUndoneMigration = function(from, to, callback) {
+    var self = this
+
+    self.findOrCreateSequelizeMetaModel().success(function(SequelizeMeta) {
+      SequelizeMeta
+        .find({ from: from.migrationId, to: to.migrationId })
+        .success(function(meta) {
+          meta.destroy().success(callback)
+        })
+    })
+  }
+
   return Migrator
   return Migrator
 })()
 })()