fixed linting errors

lib/transmissions.js

@@ -64,7 +64,7 @@ module.exports = function(client) {
         return Promise.reject(new Error('transmission object is required')).asCallback(callback);
       }
 
-      let modifiedTransmission = _.cloneDeep(transmission);
+      const modifiedTransmission = _.cloneDeep(transmission);
 
       // Handle optional options argument
       if (typeof options === 'function') {
@@ -112,8 +112,8 @@ function formatPayload(transmission) {
 
 function addListToRecipients(transmission, listName) {
   if (_.has(transmission, listName) && _.isArray(transmission[listName])) {
-    let headerTo = generateHeaderTo(transmission.recipients)
-      , list = transmission[listName];
+    const headerTo = generateHeaderTo(transmission.recipients);
+    const list = transmission[listName];
 
     transmission.recipients = transmission.recipients.concat(_.map(list, (recipient) => {
       recipient.address = addressToObject(recipient.address);
@@ -136,25 +136,19 @@ function addCCHeader(transmission) {
   // default the headers to a blank object
   transmission.content.headers = transmission.content.headers || {};
 
-  transmission.content.headers.CC = _.map(transmission.cc, (ccRecipient) => {
-    return addressToString(ccRecipient.address);
-  }).join(', ');
+  transmission.content.headers.CC = _.map(transmission.cc, (ccRecipient) => addressToString(ccRecipient.address)).join(', ');
 }
 
 function generateHeaderTo(recipients) {
-  let originalRecipients = _.filter(recipients, (recipient) => {
-    return !_.has(recipient.address, 'header_to');
-  });
+  const originalRecipients = _.filter(recipients, (recipient) => !_.has(recipient.address, 'header_to'));
 
-  return _.map(originalRecipients, (recipient) => {
-    return addressToString(recipient.address);
-  }).join(', ');
+  return _.map(originalRecipients, (recipient) => addressToString(recipient.address)).join(', ');
 }
 
 function addressToString(address) {
   if (!_.isString(address)) {
     if (_.has(address, 'name')) {
-      address = '"' + address.name + '" <' + address.email + '>';
+      address = `"${address.name}" <${address.email}>`;
     } else {
       address = address.email;
     }
@@ -172,13 +166,13 @@ function addressToObject(address) {
     if (isEmail(address)) {
       addressObject.email = address;
     } else {
-      let matches = /"?(.[^"]*)?"?\s*<(.+)>/gi.exec(address);
+      const matches = /"?(.[^"]*)?"?\s*<(.+)>/gi.exec(address);
 
       if (matches) {
         addressObject.name = matches[1];
         addressObject.email = matches[2];
       } else {
-        throw new Error('Invalid address format: ' + address);
+        throw new Error(`Invalid address format: ${address}`);
       }
     }
   }
@@ -187,6 +181,6 @@ function addressToObject(address) {
 }
 
 function isEmail(email) {
-  let emailRegex = /^[-a-z0-9~!$%^&*_=+}{\'?]+(\.[-a-z0-9~!$%^&*_=+}{\'?]+)*@([a-z0-9_][-a-z0-9_]*(\.[-a-z0-9_]+[a-z][a-z])|([0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}))(:[0-9]{1,5})?$/i;
+  const emailRegex = /^[-a-z0-9~!$%^&*_=+}{\'?]+(\.[-a-z0-9~!$%^&*_=+}{\'?]+)*@([a-z0-9_][-a-z0-9_]*(\.[-a-z0-9_]+[a-z][a-z])|([0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}))(:[0-9]{1,5})?$/i;
   return emailRegex.test(email);
 }