Hey!

Before Symfony 2.3, all form types use the FormType as base type allowing us to easily override all form types via a form type extension which uses form as parent extended type. Since Symfony 2.3, the button types have been introduced but they are a specific kind of types which don't use the FormType as base form. Because of that, we need to create two form types extension if we want to override all form types (one for the form & an other for the button).

IMO, since all types don't use the same base form (FormType), the form type extension should allow to override more than one type by returning a string (to maintain the BC) or an array of extended parent types. What do you think?