I have a simple schema with multiple keys a,b,c,d , all of them are string .
i want to validate such that between a and b only 1 of them should be present at a time. and the same for c and d

I am using the xor validation that Joi provides to achieve that but I want to set a custom message for each xor group when it fails.
sadly i am only getting the custom message of the last xor for whichever group errors out.

const schema = Joi.object({
    a: Joi.string(),
    b: Joi.string(),
    c: Joi.string(),
    d: Joi.string()
})
    .xor("a", "b")
    .messages({
        "object.xor": "either a or b must be present but not both "
    })
    .xor("c", "d")
    .messages({
        "object.xor": "either c or d must be present but not both "
    });

const data = {
    a: "not-empty",
    b: "not-empty",
    c: "not-empty",
    d: "not-empty"
};

const result = schema.validate(data, {
    abortEarly: false
});

I get the below output

{
  value: { a: 'not-empty', b: 'not-empty', c: 'not-empty', d: 'not-empty' },
  error: [Error [ValidationError]: either c or d must be present but not both ] {
    _original: { a: 'not-empty', b: 'not-empty', c: 'not-empty', d: 'not-empty' },
    details: [ [Object], [Object] ]
  }
}

I expected it to throw error for both a and b and as well as c and d group . But i could only get the last message . Please let me know if there is any other way i can set custom message for each xor validation.