RangeError: Maximum call stack size exceeded - when using Joi.alternatives().try() inside alter()

BrandonNoad commented 1 year ago

Support plan

is this issue currently blocking your project? yes (though I can likely find a workaround)
is this issue affecting a production system? yes

Context

node version: 16.15.1
module version with issue: 17.14.1
last module version without issue: unknown
environment (e.g. node, browser, native): node
used with (e.g. hapi application, another framework, standalone, ...): hapi application
any other relevant information: I was able to reproduce the error on the Joi sandbox, https://joi.dev/tester/

What are you trying to achieve or the steps to reproduce?

I want to tailor an existing schema to allow it or an alternative schema.

Schema:

Joi.object({
    key: Joi.string()
})
    .alter({
        patch: (schema) => Joi.alternatives().try(schema, Joi.object({ state: Joi.string().required() }))
    })
    .tailor('patch')

Data to Validate:

{ state: 'inactive' }

What was the result you got?

RangeError: Maximum call stack size exceeded

What result did you expect?

Validation Passed ({ state: 'inactive' })

Cursor_and_joi_dev_-_Schema_Tester_v17_8_3

Marsup commented 1 year ago

Tailored schemas are done deeply, so the problem with this is that you have created your own infinite loop that you need to break out of.

Something like this should work:

Joi.object({
  key: Joi.string(),
})
  .alter({
    patch: (schema) =>
      schema.$_getFlag("altered")
        ? schema
        : Joi.alternatives().try(
            schema.$_setFlag("altered", true),
            Joi.object({ state: Joi.string().required() })
          ),
  })
  .tailor("patch");

BrandonNoad commented 1 year ago

@Marsup Thanks for the quick response. Your solution resolves the error 🎉 .

hapijs / joi