isabanin/pretty_diff — pull request #11 by chrisledet (2013-09-02 15:44:57+00:00)
Title: Fix validating generator

```ruby
def valid_generator?(generator)
# other conditions
gen.superclass == AbstractGenerator
end
```

The above line only works for classes that directly inherit from `AbstractGenerator`. This patch allows any subclass of `AbstractGenerator` to be validated as a generator.