1 files changed, 57 insertions, 0 deletions
diff --git a/activerecord/test/cases/invertible_migration_test.rb b/activerecord/test/cases/invertible_migration_test.rb
new file mode 100644
index 0000000000..7e61ab0e47
--- /dev/null
+++ b/activerecord/test/cases/invertible_migration_test.rb
@@ -0,0 +1,57 @@
+require "cases/helper"
+
+module ActiveRecord
+  class InvertibleMigrationTest < ActiveRecord::TestCase
+    class SilentMigration < ActiveRecord::Migration
+      def write(text = '')
+        # sssshhhhh!!
+      end
+    end
+
+    class InvertibleMigration < SilentMigration
+      def change
+        create_table("horses") do |t|
+          t.column :content, :text
+          t.column :remind_at, :datetime
+        end
+      end
+    end
+
+    class NonInvertibleMigration < SilentMigration
+      def change
+        create_table("horses") do |t|
+          t.column :content, :text
+          t.column :remind_at, :datetime
+        end
+        remove_column "horses", :content
+      end
+    end
+
+    def treardown
+      if ActiveRecord::Base.connection.table_exists?("horses")
+        ActiveRecord::Base.connection.drop_table("horses")
+      end
+    end
+
+    def test_no_reverse
+      migration = NonInvertibleMigration.new
+      migration.migrate(:up)
+      assert_raises(IrreversibleMigration) do
+        migration.migrate(:down)
+      end
+    end
+
+    def test_up
+      migration = InvertibleMigration.new
+      migration.migrate(:up)
+      assert migration.connection.table_exists?("horses"), "horses should exist"
+    end
+
+    def test_down
+      migration = InvertibleMigration.new
+      migration.migrate :up
+      migration.migrate :down
+      assert !migration.connection.table_exists?("horses")
+    end
+  end
+end