Ids for radio inputs when using react element for choices is set incorrectly

[helenwilliamson]

What you were expecting:
When creating a RadioButtonGroupInput using a react element for the choices, I expect that the rendered inputs will have unique ids

What happened instead:
Instead the rendered inputs will end up with the same id

Steps to reproduce:
Create RadioButtonGroupInput as per https://marmelab.com/react-admin/Inputs.html#radiobuttongroupinput using a React element:

const choices = [
   { id: 123, first_name: 'Leo', last_name: 'Tolstoi' },
   { id: 456, first_name: 'Jane', last_name: 'Austen' },
];
const FullNameField = ({ record }) => <span>{record.first_name} {record.last_name}</span>;
<RadioButtonGroupInput source="gender" choices={choices} optionText={<FullNameField />}/>

Check ids for radio inputs in rendered html. They're all gender_[object Object]

Proposed fix:
Change

react-admin/packages/ra-ui-materialui/src/input/RadioButtonGroupInputItem.tsx

Line 29 in ae64892

const nodeId = `${source}_${label}`;

to the following:

const nodeId = `${source}_${value}`;

[djhi]

Hi and thanks for the report. Would you mind openning a pull request with the proposed fix?

[helenwilliamson]

done - #4928