useField sets `type` to `undefined` when not provided via FieldRenderProps

Oh hey @erikras! Long time no chat. =P

Finally am getting to use this!

Are you submitting a bug report or a feature request?

Bug!

What is the current behavior?

useField() returns input: { ...stuff, type: undefined }

What is the expected behavior?

Instead, the key should not be deifined

Sandbox Link

https://codesandbox.io/s/react-final-form-simple-example-p35vk

What's your environment?

react-final-form@6.3.0

Other information

The reason this is problematic is that, when spreading into something, it will override type: 'something' with type: undefined since the key's value is actually set to undefined. This is due to a bad optimization in the compiled output:


function useField(name, _temp) {
  var _ref = _temp === void 0 ? {} : _temp,
      afterSubmit = _ref.afterSubmit,
      allowNull = _ref.allowNull,
      beforeSubmit = _ref.beforeSubmit,
      component = _ref.component,
      defaultValue = _ref.defaultValue,
      _ref$format = _ref.format,
      format = _ref$format === void 0 ? defaultFormat : _ref$format,
      formatOnBlur = _ref.formatOnBlur,
      initialValue = _ref.initialValue,
      isEqual = _ref.isEqual,
      multiple = _ref.multiple,
      _ref$parse = _ref.parse,
      parse = _ref$parse === void 0 ? defaultParse : _ref$parse,
      _ref$subscription = _ref.subscription,
      subscription = _ref$subscription === void 0 ? all$1 : _ref$subscription,
      type = _ref.type,
      validate = _ref.validate,
      validateFields = _ref.validateFields,
      _value = _ref.value;

In the uncompiled code, there is a check for undefined before assigning to the key. In compiled code, that check is not there, and it explicitly sets type to _ref.type, which is undefined by default.

I haven't looked at this build on why this is.

final-form / react-final-form