Default value associated to oneOf element does not change with user selection

[portatlas]

Describe the bug
The default values associated with each "oneOf" selections does not get updated when a user picks another "oneOf" element. In the example below there is a oneOf selection with two available options 1.) Address (default is "address") and 2.) Socials (default is socials). When the user selects Socials the default is still address.

To Reproduce

1. Create a json form with the following schema and uischema.

const schema = {
  $schema: "http://json-schema.org/draft-07/schema#",
  definitions: {
    address: {
      type: "object",
      properties: {
        infoType: { type: "string", default: "address" },
        street_address: { type: "string" },
        city: { type: "string" },
        state: { type: "string" }
      },
      required: ["street_address", "city", "state"]
    },
    socials: {
      type: "object",
      properties: {
        infoType: { type: "string", default: "social" },
        twitter: { type: "string" },
        mail: { type: "string" }
      },
      required: ["name", "mail"]
    },
    userInfoType: {
      type: "string",
      enum: ["address", "socials"]
    }
  },
  type: "object",
  properties: {
    name: { type: "string" },
    info: {
      oneOf: [
        {
          $ref: "#/definitions/address",
          title: "Address"
        },
        {
          $ref: "#/definitions/socials",
          title: "Socials"
        }
      ]
    }
  }
};

export const uischema = {
  type: "VerticalLayout",
  elements: [
    {
      type: "Control",
      scope: "#/properties/name"
    },
    {
      type: "Control",
      scope: "#/properties/info"
    }
  ]
};

2. Click on Address and the default Info Type is address
3. Click on Socials and the default Info Type is still "address" and does not change

Expected behavior
The expected behavior, is that when a user selects a oneOf option then the associated default option for that oneOf should be updated. In this case, when a user selects "Socials" then the default InfoType should be "socials".

Screenshots
https://codesandbox.io/s/admiring-fermi-wy57n?from-embed=&file=/src/App.tsx:889-2099

Browser (please complete the following information):

• Browser [e.g. chrome, safari]
• Version [e.g. 22]

Used Setup (please complete the following information):

• Framework: react
• RendererSet: material

Additional context
Add any other context about the problem here.

[sdirix]

Hi @portatlas, thanks for the report! I understand the use case. The problem comes from our approach of validating the whole data object at once and using this to insert the defaults via Ajv. So when we switch between the different oneOf variants we just create an empty object and let Ajv do its thing.

In this case Ajv seems to always use the address default as Ajv is of course unaware of our UI semantics. To fix this we would need to handle defaults manually in this case. For example by letting Ajv do a pass only over this subschema and using the resulting object as the new object.

I'll add this to the backlog but I can't promise a specific date to implement this fix/feature. We would definitely take a look at a contribution.

Edit: Of course you can always fix issues like this with a custom renderer on your side. In this case you could add the default yourself in a custom OneOfRenderer.

[portatlas]

Hello, thanks for the detailed explanation. I ended up creating a multi-step form where the user would select the oneOf options in the first step and as they move to the next step, the form would render the dependent default values based on what was selected in the first step. This worked well for us, because the forms were long and breaking them up made sense from a UX perspective. Thanks again!