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No undefined values

noUndefinedValues validates that a plain object does not contain any undefined values in its own enumerable properties.

It performs a strict structural check ensuring the value is a plain object, then inspects each property value for undefined. If the value is not a plain object or contains any undefined values, the rule emits a single validation event. Otherwise, it produces no validation output.

Signature

Through the API:

.noUndefinedValues()

And internally:

export const noUndefinedValues: ValidationRule
(value: unknown, path: FieldPath) => Promise<ReadonlyArray<JaneEvent>>

Events

Event code Description
object.not.plain-object Value is not a JSON-compatible plain object
object.has.undefined-value Object contains at least one undefined value

Design rationale

  • Provides a strict, predictable undefined value prohibition.
  • First ensures the value is a plain object, then checks all property values.
  • Rejects any property that has exactly the undefined value.
  • Useful for enforcing strict data quality where undefined values are not allowed.
  • Never coerces or normalizes — validation is explicit and opt-in.
  • Emits exactly one event per failure for clarity and composability.
  • Async-compatible and returns a readonly array of JaneEvent objects.

Invoke

noUndefinedValues runs only when explicitly included in a boundary or pipeline. It does not run automatically.

The rule activates when:

  • The value is any JavaScript value.
  • If the value is not a plain object, emits object.not.plain-object.
  • If the value is a plain object but contains any undefined values, emits object.has.undefined-value.
  • If the value is a plain object with no undefined values → returns an empty result set.

Examples

Valid object with no undefined values

await noUndefinedValues({ name: "John", age: 30 }, "$");
// → []

Object with undefined value

await noUndefinedValues({ name: "John", age: undefined }, "$");
// → [
//     JaneEvent{
//       kind: "error",
//       code: "object.has.undefined-value",
//       path: "$",
//       ...
//     }
//   ]

Array (invalid)

await noUndefinedValues([1, 2, 3], "$");
// → [
//     JaneEvent{
//       kind: "error",
//       code: "object.not.plain-object",
//       path: "$",
//       ...
//     }
//   ]