feat: add isCronTimeValid function to validate cron expressions

#958

examples/is_crontime_valid.js

@@ -1,9 +1,3 @@
-import { CronJob } from '../src';
+import { isCronTimeValid } from '../src';
 
-try {
-	new CronJob('NOT VALID', () => {
-		console.log("shouldn't get printed");
-	});
-} catch (e) {
-	console.log('omg err', e);
-}
+console.log('is valid? ', isCronTimeValid('NOT VALID'));

src/index.ts

@@ -20,3 +20,14 @@ export const sendAt = (cronTime: string | Date | DateTime): DateTime =>
 
 export const timeout = (cronTime: string | Date | DateTime): number =>
 	new CronTime(cronTime).getTimeout();
+
+export const isCronTimeValid = (
+	cronTime: string | Date | DateTime
+): boolean => {
+	try {
+		new CronTime(cronTime);
+		return true;
+	} catch (_) {
+		return false;
+	}
+};

tests/crontime.test.ts

@@ -1,6 +1,6 @@
 import { DateTime } from 'luxon';
 import sinon from 'sinon';
-import { CronTime } from '../src';
+import { CronTime, isCronTimeValid } from '../src';
 
 describe('crontime', () => {
 	// eslint-disable-next-line jest/no-standalone-expect
@@ -778,3 +778,19 @@ describe('crontime', () => {
 		}).toThrow();
 	});
 });
+
+describe('isCronTimeValid', () => {
+	it('should return true for valid cron expressions', () => {
+		expect(isCronTimeValid('* * * * *')).toBe(true);
+		expect(isCronTimeValid('0 0 * * *')).toBe(true);
+		expect(isCronTimeValid('0 0 1 1 *')).toBe(true);
+		expect(isCronTimeValid('*/5 * * * *')).toBe(true);
+	});
+
+	it('should return false for invalid cron expressions', () => {
+		expect(isCronTimeValid('* * * *')).toBe(false);
+		expect(isCronTimeValid('60 * * * *')).toBe(false);
+		expect(isCronTimeValid('* * * * * * *')).toBe(false);
+		expect(isCronTimeValid('invalid cron')).toBe(false);
+	});
+});