current version:
```
2.0.0-p247 :001 > options = {}
 => {}
2.0.0-p247 :002 > (options[:env] || {}).merge!("AUTOTEST" => "1")
 => {"AUTOTEST"=>"1"}
2.0.0-p247 :003 > options
 => {}
```

fixed version:

```
2.0.0-p247 :001 > options = {}
 => {}
2.0.0-p247 :002 > (options[:env] ||= {}).merge!("AUTOTEST" => "1")
 => {"AUTOTEST"=>"1"}
2.0.0-p247 :003 > options
 => {:env=>{"AUTOTEST"=>"1"}}
```