fixed/ email issue

src/lib/isEmail.js

@@ -1,5 +1,4 @@
 import assertString from './util/assertString';
-
 import isByteLength from './isByteLength';
 import isFQDN from './isFQDN';
 import isIP from './isIP';
@@ -17,165 +16,79 @@
   host_whitelist: [],
 };
 
-/* eslint-disable max-len */
-/* eslint-disable no-control-regex */
-const splitNameAddress = /^([^\x00-\x1F\x7F-\x9F\cX]+)</i;
-const emailUserPart = /^[a-z\d!#\$%&'\*\+\-\/=\?\^_`{\|}~]+$/i;
-const gmailUserPart = /^[a-z\d]+$/;
-const quotedEmailUser = /^([\s\x01-\x08\x0b\x0c\x0e-\x1f\x7f\x21\x23-\x5b\x5d-\x7e]|(\\[\x01-\x09\x0b\x0c\x0d-\x7f]))*$/i;
-const emailUserUtf8Part = /^[a-z\d!#\$%&'\*\+\-\/=\?\^_`{\|}~\u00A1-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF]+$/i;
 const quotedEmailUserUtf8 = /^([\s\x01-\x08\x0b\x0c\x0e-\x1f\x7f\x21\x23-\x5b\x5d-\x7e\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF]|(\\[\x01-\x09\x0b\x0c\x0d-\x7f\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF]))*$/i;
-const defaultMaxEmailLength = 254;
-/* eslint-enable max-len */
-/* eslint-enable no-control-regex */
-
-/**
- * Validate display name according to the RFC2822: https://tools.ietf.org/html/rfc2822#appendix-A.1.2
- * @param {String} display_name
- */
-function validateDisplayName(display_name) {
-  const display_name_without_quotes = display_name.replace(/^"(.+)"$/, '$1');
-  // display name with only spaces is not valid
-  if (!display_name_without_quotes.trim()) {
-    return false;
-  }
-
-  // check whether display name contains illegal character
-  const contains_illegal = /[\.";<>]/.test(display_name_without_quotes);
-  if (contains_illegal) {
-    // if contains illegal characters,
-    // must to be enclosed in double-quotes, otherwise it's not a valid display name
-    if (display_name_without_quotes === display_name) {
-      return false;
-    }
-
-    // the quotes in display name must start with character symbol \
-    const all_start_with_back_slash =
-      display_name_without_quotes.split('"').length === display_name_without_quotes.split('\\"').length;
-    if (!all_start_with_back_slash) {
-      return false;
-    }
-  }
-
-  return true;
-}
-
+const quotedEmailUser = /^([\s\x21\x23-\x5b\x5d-\x7e]|(\\[\x01-\x09\x0b\x0c\x0d-\x7f]))*$/i;
 
 export default function isEmail(str, options) {
   assertString(str);
   options = merge(options, default_email_options);
 
   if (options.require_display_name || options.allow_display_name) {
     const display_email = str.match(splitNameAddress);
     if (display_email) {
       let display_name = display_email[1];
 
-      // Remove display name and angle brackets to get email address
-      // Can be done in the regex but will introduce a ReDOS (See  #1597 for more info)
       str = str.replace(display_name, '').replace(/(^<|>$)/g, '');
 
-      // sometimes need to trim the last space to get the display name
-      // because there may be a space between display name and email address
-      // eg. myname <address@gmail.com>
-      // the display name is `myname` instead of `myname `, so need to trim the last space
       if (display_name.endsWith(' ')) {
         display_name = display_name.slice(0, -1);
       }
 
       if (!validateDisplayName(display_name)) {
         return false;
       }
     } else if (options.require_display_name) {
       return false;
     }
   }
+
   if (!options.ignore_max_length && str.length > defaultMaxEmailLength) {
     return false;
   }
 
   const parts = str.split('@');
-  const domain = parts.pop();
-  const lower_domain = domain.toLowerCase();
+  const domain = parts.pop().toLowerCase();
 
-  if (options.host_blacklist.includes(lower_domain)) {
+  if (options.host_blacklist.includes(domain)) {
     return false;
   }
 
-  if (options.host_whitelist.length > 0 && !options.host_whitelist.includes(lower_domain)) {
+  if (options.host_whitelist.length > 0 && !options.host_whitelist.includes(domain)) {
     return false;
   }
 
   let user = parts.join('@');
 
   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(/\./g, ''), { 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;
       }
     }
   }
 
-  if (options.ignore_max_length === false && (
-    !isByteLength(user, { max: 64 }) ||
-    !isByteLength(domain, { max: 254 }))
-  ) {
-    return false;
-  }
-
-  if (!isFQDN(domain, {
-    require_tld: options.require_tld,
-    ignore_max_length: options.ignore_max_length,
-    allow_underscores: options.allow_underscores,
-  })) {
-    if (!options.allow_ip_domain) {
+  if (!isFQDN(domain, { require_tld: options.require_tld })) {
+    if (!options.allow_ip_domain || !isIP(domain)) {
       return false;
     }
-
-    if (!isIP(domain)) {
-      if (!domain.startsWith('[') || !domain.endsWith(']')) {
-        return false;
-      }
-
-      let noBracketdomain = domain.slice(1, -1);
-
-      if (noBracketdomain.length === 0 || !isIP(noBracketdomain)) {
-        return false;
-      }
-    }
   }
 
-  if (options.blacklisted_chars) {
-    if (user.search(new RegExp(`[${options.blacklisted_chars}]+`, 'g')) !== -1) return false;
+  if (options.blacklisted_chars && user.search(new RegExp(`[${options.blacklisted_chars}]`, 'g')) !== -1) {
+    return false;
   }
 
   if (user[0] === '"' && user[user.length - 1] === '"') {
-    user = user.slice(1, user.length - 1);
-    return options.allow_utf8_local_part ?
-      quotedEmailUserUtf8.test(user) :
-      quotedEmailUser.test(user);
+    user = user.slice(1, -1);
+    return options.allow_utf8_local_part ? quotedEmailUserUtf8.test(user) : quotedEmailUser.test(user);
   }
 
-  const pattern = options.allow_utf8_local_part ?
-    emailUserUtf8Part : emailUserPart;
-
+  const pattern = options.allow_utf8_local_part ? emailUserUtf8Part : emailUserPart;
   const user_parts = user.split('.');
   for (let i = 0; i < user_parts.length; i++) {
     if (!pattern.test(user_parts[i])) {