Skip to content

Is past

isPast validates that a Date instance represents a moment strictly before the current system time.

It performs a strict type check ensuring the value is a valid Date instance, then validates that the timestamp is less than the current time. If the value is not a Date, is invalid, or represents a future/present time, the rule emits a single validation event. Otherwise, it produces no validation output.

Signature

Through the API:

.isPast()

And internally:

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

Events

Event code Description
date.not.date Value is not a Date instance
date.is.invalid Date instance represents an invalid date
date.in.future Date represents present time or future time

Design rationale

  • Provides a strict, predictable past date validation.
  • First ensures the value is a valid Date instance.
  • Then validates the timestamp is strictly less than current time.
  • Useful for ensuring dates represent completed events or historical data.
  • 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

isPast 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 Date instance, emits date.not.date.
  • If the value is a Date but invalid, emits date.is.invalid.
  • If the value is a valid Date but represents present/future time, emits date.in.future.
  • If the value is a valid past Date → returns an empty result set.

Examples

Past date

await isPast(new Date("2023-01-01"), "$");
// → []

Future date

await isPast(new Date(Date.now() + 86400000), "$");
// → [
//     JaneEvent{
//       kind: "error",
//       code: "date.in.future",
//       path: "$",
//       ...
//     }
//   ]

Non-Date value

await isPast("2023-01-01", "$");
// → [
//     JaneEvent{
//       kind: "error",
//       code: "date.not.date",
//       path: "$",
//       ...
//     }
//   ]