Do you know `hello@gmail.com` is not a valid format?

  it.only('should validate email addresses with domain specific validation', () => {
    test({
      validator: 'isEmail',
      args: [{ domain_specific_validation: true }],
      valid: [
        'foo@bar.com',
        'hello@gmail.com',
      ],
      invalid: [
        `${repeat('a', 31)}@gmail.com`,
        'test@gmail.com',
        'test.1@gmail.com',
      ],
    });
  });

> validator@10.11.0 test /Users/mac9/project/open-src/validator.js
> mocha --require @babel/register

  Validators
    1) should validate email addresses with domain specific validation


  0 passing (127ms)
  1 failing

  1) Validators
       should validate email addresses with domain specific validation:
     Error: validator.isEmail(hello@gmail.com, [object Object]) failed but should have passed
      at /Users/mac9/project/open-src/validator.js/test/validators.js:20:15
      at Array.forEach (<anonymous>)
      at forEach (test/validators.js:13:19)
      at Context.test (test/validators.js:107:5)


npm ERR! Test failed.  See above for more details.

Process finished with exit code 1

// ...
export default function isEmail(str, options) {
  assertString(str);
  options = merge(options, default_email_options);
// ...
  if (options.domain_specific_validation && (lower_domain === 'gmail.com' || lower_domain === 'googlemail.com')) {
    /*
      Previously we removed dots for gmail addresses before validating.
      This was removed because it allows `multiple..dots@gmail.com`
      to be reported as valid, but it is not.
      Gmail only normalizes single dots, removing them from here is pointless,
      should be done in normalizeEmail
    */
    user = user.toLowerCase();

    // Removing sub-address from username before gmail validation
    const username = user.split('+')[0];

    // Dots are not included in gmail length restriction
    if (!isByteLength(username.replace('.', ''), { min: 6, max: 30 })) {
      return false;
    }

    const user_parts = username.split('.');
    for (let i = 0; i < user_parts.length; i++) {
      if (!gmailUserPart.test(user_parts[i])) {
        return false;
      }
    }
  }
// ...