Date range¶

dateRange validates that a start and end date form a proper chronological range.

If both fields resolve to valid Date objects and the start occurs after the end, the rule emits a boundary‑level error. This rule is ideal for validating temporal windows such as availability periods, enrollment windows, publication ranges, or any domain where chronological ordering matters.

Signature¶

export function dateRange(startKey: string, endKey: string): BoundaryRule

Parameters¶

Parameter	Data type	Description
`startKey`	`string`	The field expected to contain the start date.
`endKey`	`string`	The field expected to contain the end date.

Events¶

Event code	Description
`boundary.does.require-date-range`	The start date occurred after the end date.

Design rationale¶

Activates only when both fields resolve to actual Date instances.
Compares the two dates directly (start > end).
Emits a single boundary‑level error when the chronological order is invalid.
Does not modify field values or decisions — it only adds boundary‑level issues.
Keeps contributor expectations clear by enforcing explicit temporal ordering rules.

Invoke¶

dateRange runs during the boundary decision phase. It is not affected by normalization mode or parsing rules.

The rule activates when:

fields[startKey]?.final is a Date.
fields[endKey]?.final is a Date.
The start date is chronologically after the end date.

Examples¶

Valid date range¶

dateRange("startDate", "endDate");

// startDate = 2024‑01‑01
// endDate   = 2024‑01‑31
// → OK (no boundary issues)

Invalid date range¶

dateRange("startDate", "endDate");

// startDate = 2024‑02‑01
// endDate   = 2024‑01‑31
// → boundary.does.require-date-range at $

Missing or non‑date values — rule does nothing¶

dateRange("start", "end");

// start = undefined
// end   = new Date()
// → no comparison performed