Breaking: removes YYYY and YYYYMM formats. All valid dates here are now valid Temporal dates (not necessarily the other way though) and runs all tests through Temporal polyfill. Also fixes bug with error reporting on fractional hours and minutes.

Author: zachleat

package-lock.json

@@ -20,6 +20,7 @@
 	"license": "MIT",
 	"devDependencies": {
 		"luxon": "^3.7.1",
+		"temporal-polyfill": "^0.3.0",
 		"vitest": "^3.2.4"
 	},
 	"author": "Zach Leatherman <[email protected]> (https://zachleat.com/)",

package.json

@@ -1,22 +1,18 @@
 // Times are parsed as UTC if no offset is specified
-
-class IsoDateParts {
+export class IsoDateParts {
 	static DEFAULT_TIMEZONE_OFFSET = {
 		hours: 0,
 		minutes: 0,
 	};
 
-	static VAGUE_DATE_REGEX = /^\d{5,7}$/;
-	static PARTIAL_DATE_REGEX = /^(\d{4})(?:-([01]\d)(?:-([0-3]\d))?)?$/;
-	static FULL_DATE_REGEX = /^(\d{4})-?([01]\d)-?([0-3]\d)$/; // dashes optional when 8 digits
-	
-	static VAGUE_DATETIME_REGEX = /^(\d{4})-?([01]\d)-?([0-3]\d)T(\d{1}|\d{3}|\d{5})(?:[\.\,](\d+))?([+-]\d{2}:?\d{2}|Z)?$/;
-	static DATETIME_REGEX = /^(\d{4})-?([01]\d)-?([0-3]\d)T([0-2]\d)(?::?([0-5]\d))?(?::?([0-5]\d))?(?:[\.\,](\d+))?(Z|[+-][0-2]\d(?::?[0-5]\d)?)?$/;
+	static FULL_DATE_REGEX = /^(\d{4})-?([01]\d)-?([0-3]\d)$/;
+	static DATETIME_REGEX = /^(\d{4})-?([01]\d)-?([0-3]\d)T([0-2]\d(?:[\.\,]\d+)?)(?::?([0-5]\d(?:[\.\,]\d+)?)(?::?([0-5]\d))?(?:[\.\,](\d+))?)?(Z|[+-][0-2]\d(?::?[0-5]\d)?)?$/;
+	static TIMEZONE_REGEX = /^([+-]\d{2})(?::?(\d{2}))?$/;
+	static IS_FRACTIONAL_REGEX = /^\d+[\.\,]\d+$/;
 
-	// this format is cursed, burn it with fire https://en.wikipedia.org/wiki/ISO_week_date
-	static DATE_WEEK_REGEX = /^(\d{4})-W\d{2}-?\d{0,1}/; // unsupported
-	static YEARDAY_REGEX = /^(\d{4})-?\d{3}$/; // unsupported
-	static TIMEZONE_REGEX = /^([+-]\d{2})(?::?(\d{2}))?$/; // unsupported
+	// Unsupported formats https://en.wikipedia.org/wiki/ISO_week_date
+	static DATE_WEEK_REGEX = /^(\d{4})-W\d{2}-?\d{0,1}/;
+	static YEARDAY_REGEX = /^(\d{4})-?\d{3}$/;
 
 	static getTimezoneOffset(offset = "") {
 		if(offset === "Z") {
@@ -51,35 +47,28 @@ class IsoDateParts {
 
 	static getParts(str) {
 		if(str.match(this.DATE_WEEK_REGEX) || str.match(this.YEARDAY_REGEX)) {
-			throw new Error(`Unsupported date format (dropped syntax): ${str}`);
-		}
-
-		if(str.match(this.VAGUE_DATE_REGEX)) {
-			throw new Error(`Unsupported date format (vague date): ${str}`);
+			throw new Error(`Unsupported date format (unsupported syntax): ${str}`);
 		}
 
-		let dateMatch = str.match(this.PARTIAL_DATE_REGEX) || str.match(this.FULL_DATE_REGEX);
+		let dateMatch = str.match(this.FULL_DATE_REGEX);
 		if(dateMatch) {
 			return this.getByDateTime(dateMatch);
 		}
 
-		let vagueDatetime = str.match(this.VAGUE_DATETIME_REGEX);
-		if(vagueDatetime) {
-			throw new Error(`Unsupported date format (vague datetime): ${str}`);
-		}
-
 		let dateTimeMatch = str.match(this.DATETIME_REGEX);
 		if(dateTimeMatch) {
+			if(dateTimeMatch[4]?.match(this.IS_FRACTIONAL_REGEX) || dateTimeMatch[5]?.match(this.IS_FRACTIONAL_REGEX)) {
+				throw new Error(`Unsupported date format (fractional hours or minutes): ${str}`);
+			}
+
 			return this.getByDateTime(dateTimeMatch);
 		}
 
-		throw new Error(`Unsupported date format (unknown): ${str}`);
+		throw new Error(`Unsupported date format: ${str}`);
 	}
 }
 
-class IsoDate {
-	#source;
-
+export class IsoDate {
 	static parse(str) {
 		let parts = IsoDateParts.getParts(str);
 		if(parts) {
@@ -102,14 +91,6 @@ class IsoDate {
 		return [this.year, this.month, this.day, this.hours, this.minutes, this.seconds, this.milliseconds];
 	}
 
-	set source(val) {
-		this.#source = val;
-	}
-
-	get source() {
-		return this.#source;
-	}
-
 	checkParts() {
 		// months: 0-indexed, 0–11 are valid
 		if(this.month < 0 || this.month > 11) {
@@ -123,4 +104,6 @@ class IsoDate {
 	}
 }
 
-export { IsoDate };
+export function parse(str) {
+	return IsoDate.parse(str);
+}