Fixes issue #381 invalid day format for date validation rule

Author: justin-schroeder

dist/formulate.esm.js

@@ -228,7 +228,7 @@ export function regexForFormat (format) {
     MM: '(0[1-9]|1[012])',
     M: '([1-9]|1[012])',
     DD: '([012][0-9]|3[01])',
-    D: '([012]?[1-9]|3[01])',
+    D: '([012]?[0-9]|3[01])',
     YYYY: '\\d{4}',
     YY: '\\d{2}'
   }

dist/formulate.min.js

@@ -192,6 +192,8 @@ describe('date', () => {
 
   it('passes with valid date format', async () => expect(await rules.date({ value: '12/10/1987' }, 'MM/DD/YYYY')).toBe(true))
 
+  it('passes with date ending in zero', async () => expect(await rules.date({ value: '12/10/1987' }, 'MM/D/YYYY')).toBe(true))
+
   it('fails with simple number and date format', async () => expect(await rules.date({ value: '1234' }, 'MM/DD/YYYY')).toBe(false))
 
   it('fails with only day of week', async () => expect(await rules.date({ value: 'saturday' })).toBe(false))