Function possiblyCollapse

ark/schema/parse.ts:340–362

(
	json: dict,
	toKey: string | undefined,
	allowPrimitive: allowPrimitive
)

}

const possiblyCollapse = <allowPrimitive extends boolean>(
	json: dict,
	toKey: string | undefined,
	allowPrimitive: allowPrimitive
): [allowPrimitive] extends [false] ? dict : unknown => {
	const collapsibleKeys = Object.keys(json)
	if (collapsibleKeys.length === 1 && collapsibleKeys[0] === toKey) {
		const collapsed = json[toKey]

		if (allowPrimitive) return collapsed as never

		if (
			// if the collapsed value is still an object
			hasDomain(collapsed, "object") &&
			// and the JSON did not include any implied keys
			(Object.keys(collapsed).length === 1 || Array.isArray(collapsed))
		) {
			// we can replace it with its collapsed value
			return collapsed as never
		}
	}
	return json as never
}