rails/rails — pull request #8636 by senny (2012-12-28 00:56:13+00:00)
Title: WIP: work off FIXME in rename_column_test

This PR is work in progress and should not be merged.

While fixing a bug related to rename_column (#8613) I noticed the FIXME comments and I wanted to work them off before I finish my bugfix.

While working on the FIXME I noticed three things:

1. ) Is it intentional that the first two lines in this test are the same? If so, what is the purpose?

```ruby
def test_change_type_of_not_null_column
change_column "test_models", "updated_at", :datetime, :null => false
change_column "test_models", "updated_at", :datetime, :null => false
change_column "test_models", "updated_at", :datetime, :null => true
end
```
2.) the FIXME in `rename_column` said: "we should test that the index goes away". Should the index go away when we rename? Currently it stays as is. Should the index be renamed if the name was generated by rails?

3.) the FIXME in `test_remove_column_with_multi_column_index` said: "we should test that the index goes away". Currently only PostgreSQL drops the index. Both MySQL and SQLite keep the index. Should I write the test for postgres only?