[DX] Form Types location contradicts Best Practices

[pbowyer]

I wondered why I always put form definitions in AppBundle/Form/Type, and whether we were meant to put something else in AppBundle/Form. While Googling for an answer I came across the Forms Best Practice guide, which says the new best practice is to put the form types (which I guess are usually form definitions, so the change makes sense) directly in AppBundle/Form.

This PR updates the main documentation to reflect the best practices. If anyone can point me to discussions clarifying the difference between form types, form definitions and how the Symfony view has changed (reflected in the change of location) I'd greatly appreciate it.

[xabbuh]

👍

[wouterj]

Hi @pbowyer!

First of all: 👍 I like this a lot. However, we have to merge changes in the oldest branch and then merge them up into the newer ones. As there has been a lot of form refactorings between 2.3 (oldest) and 3.0 (your current branch), I can't make a nice merge. If possible, can you please redo these changes against the 2.3 version of the docs? (if it's not possible, just comment and we'll do it for you)

Then to answer your question: There is no difference between form types and form definitions in Symfony. Each form consists of a root form type, which has children. The children can have children as well, etc. So each field is the end of a branch of this form tree, where node is a form type. This has some big benefits, one of these is that you can reuse "form definitions" in other forms. So an CreateAddressFormType can be used as the root form type when a user adds a new address, but it can also be included in a CreateUserFormType.

The discussion about the location change can be found here: #6059

[theofidry]

whether we were meant to put something else in AppBundle/Form

You can also have transformers (AppBundle/Form/DataTransformer) and extensions (AppBundle/Form/Extension).

That being said, I agree with @weaverryan comment. But the cookbook needs to be updated as well.

[pbowyer]

Hi @wouterj,

If possible, can you please redo these changes against the 2.3 version of the docs? (if it's not possible, just comment and we'll do it for you)

I've made the changes here, but couldn't work out how to get them into the patch-3 branch to show against this ticket, as that's a 3.0 branch. If you can tell me, I'll do it :)

[wouterj]

Hi @pbowyer. I'm very sorry to have completely ignored you to this moment.

Can you maybe create a new pull request with that branch against 2.3? We'll close this one then and things can be merged. Thanks for your work!

[wouterj]

Hi @pbowyer! Thanks for creating this PR.

I've rebased this PR to the 2.7 branch in #6733 . I'll merge that PR soon.