Nested FormSection

[adelin-b]

Hello
Is there any way to use sections like https://redux-form.com/7.4.2/docs/api/formsection.md/
If not, how can we implement it ?

[bmv437]

*Note - This is brain dump for now. I'll try and organize this into a more cohesive explanation later.

This was explored a bit in #24, but in the process of writing up an example I uncovered an issue.
The issue has to do with data scope and questionId references.

Currently data in array items has a merged scope. The arrayItem type uses the <FormSection /> component to scope it's childFields.
data = { ...formData, ...arrayItemData }
This could also be read as
data = { ...globalScope, ...localScope }
or
data = { ...absoluteData, ...relativeData }
where localScope is data that has a prefix from a <FormSection />

The merged scope is passed into condEval() which can cause issues for validation and conditional properties. This is especially true if there is a name collision for a local questionId and a global questionId.

redux-form Field components don't get a merged scope, they only see the localScope.

We need a way to differentiate between questionIds in conditional objects that refer to local scope vs global scope.

The default scope should be local, but we should be able to override that to break out of a local scope and refer to something at the global scope level.

In addition, the mapFieldChildren() utility will always traverse childFields, so it's breaking validation for a section with a questionId to scope it's childFields.