add convenience methods for checking migrations

if a rails project needs to be migrated ActiveRecord::Migrator.needs_migration? will be true or false if the current version matches the last version. 

1 files changed, 15 insertions, 0 deletions

diff --git a/activerecord/test/cases/migration_test.rb b/activerecord/test/cases/migration_test.rb
index 5d1bad0d54..45c847bae8 100644
--- a/activerecord/test/cases/migration_test.rb
+++ b/activerecord/test/cases/migration_test.rb
@@ -56,6 +56,21 @@ class MigrationTest < ActiveRecord::TestCase
     Person.reset_column_information
   end
 
+  def test_migrator_versions
+    migrations_path = MIGRATIONS_ROOT + "/valid"
+    ActiveRecord::Migrator.migrations_paths = migrations_path
+
+    ActiveRecord::Migrator.up(migrations_path)
+    assert_equal 3, ActiveRecord::Migrator.current_version
+    assert_equal 3, ActiveRecord::Migrator.last_version
+    assert_equal false, ActiveRecord::Migrator.needs_migration?
+
+    ActiveRecord::Migrator.down(MIGRATIONS_ROOT + "/valid")
+    assert_equal 0, ActiveRecord::Migrator.current_version
+    assert_equal 3, ActiveRecord::Migrator.last_version
+    assert_equal true, ActiveRecord::Migrator.needs_migration?
+  end
+
   def test_create_table_with_force_true_does_not_drop_nonexisting_table
     if Person.connection.table_exists?(:testings2)
       Person.connection.drop_table :testings2