validate MMDDYYYY format using Moment

You can have the expected output using last vesion (2.24.0), instead of the old 2.2.1.

Here a live sample:

var dates = "08291975";
var passed = moment(dates, 'MMDDYYYY', true).isValid();
console.log('should pass ' + passed);

dates = "082919751"; //one extra digit
passed = moment(dates, 'MMDDYYYY', true).isValid();
console.log('should not pass ' + passed);

dates = "0829ssss";
passed = moment(dates, 'MMDDYYYY', true).isValid();
console.log('should not pass ' + passed);

dates = "0829197"; //one digit missing
passed = moment(dates, 'MMDDYYYY', true).isValid();
console.log('should not pass ' + passed);
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