fix: make parser more resilient to extra whitespaces

src/cron-parser.ts

@@ -175,7 +175,8 @@ export function parseCronExpression(cronExpression: string): Cron {
 	// biome-ignore lint/style/noParameterAssign: adding another variable with a new name is more confusing
 	cronExpression = timeNicknames[cronExpression.toLowerCase()] ?? cronExpression
 
-	const elements = cronExpression.split(' ')
+	// Split the cron expression into its elements, removing empty elements (extra whitespaces).
+	const elements = cronExpression.split(' ').filter((elem) => elem.length > 0)
 	if (elements.length < 5 || elements.length > 6) {
 		throw new Error('Invalid cron expression: expected 5 or 6 elements.')
 	}

test/cron-parser.test.ts

@@ -472,4 +472,17 @@ describe('parseCronExpression', () => {
 			new Error('Failed to parse step: Expected 0 to be greater than 0.'),
 		)
 	})
+
+	test('it should be resilient to extra whitespaces', () => {
+		expect(
+			parseCronExpression('    *    *    *      *         * *     '),
+		).toMatchObject({
+			seconds: Array.from({ length: 60 }, (_, i) => i),
+			minutes: Array.from({ length: 60 }, (_, i) => i),
+			hours: Array.from({ length: 24 }, (_, i) => i),
+			days: Array.from({ length: 31 }, (_, i) => i + 1),
+			months: Array.from({ length: 12 }, (_, i) => i),
+			weekdays: Array.from({ length: 7 }, (_, i) => i),
+		})
+	})
 })