use EmailHelper.parseEmail on registration

Also changed EmailHelper to use the regexp already used in
UserRegistrationHandler rather than the `mimelib` package as it is
deprecated.

services/web/app/coffee/Features/Helpers/EmailHelper.coffee

@@ -1,11 +1,12 @@
-mimelib = require("mimelib")
-
+EMAIL_REGEXP = /^(([^<>()[\]\\.,;:\s@\"]+(\.[^<>()[\]\\.,;:\s@\"]+)*)|(\ ".+\"))@((\[[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\])|(([a-zA -Z\-0-9]+\.)+[a-zA-Z]{2,}))$/
 
 module.exports = EmailHelper =
 
 	parseEmail: (email) ->
-			email = mimelib.parseAddresses(email or "")[0]?.address?.toLowerCase()
-			if !email? or email == ""
-				return null
-			else
-				return email
+		return null unless email?
+		email = email.trim().toLowerCase()
+
+		matched = email.match EMAIL_REGEXP
+		return null unless matched? && matched[0]?
+
+		matched[0]

services/web/app/coffee/Features/User/UserRegistrationHandler.coffee

@@ -11,12 +11,9 @@ EmailHandler = require("../Email/EmailHandler")
 OneTimeTokenHandler = require "../Security/OneTimeTokenHandler"
 Analytics = require "../Analytics/AnalyticsManager"
 settings = require "settings-sharelatex"
+EmailHelper = require("../Helpers/EmailHelper")
 
 module.exports = UserRegistrationHandler =
-	validateEmail : (email) ->
-		re = /^(([^<>()[\]\\.,;:\s@\"]+(\.[^<>()[\]\\.,;:\s@\"]+)*)|(\ ".+\"))@((\[[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\])|(([a-zA -Z\-0-9]+\.)+[a-zA-Z]{2,}))$/
-		return re.test(email)
-
 	hasZeroLengths : (props) ->
 		hasZeroLength = false
 		props.forEach (prop) ->
@@ -25,13 +22,10 @@ module.exports = UserRegistrationHandler =
 		return hasZeroLength
 
 	_registrationRequestIsValid : (body, callback)->
-		email = sanitize.escape(body.email).trim().toLowerCase()
+		email = EmailHelper.parseEmail(body.email) or ''
 		password = body.password
-		username = email.match(/^[^@]*/)
 		if @hasZeroLengths([password, email])
 			return false
-		else if !@validateEmail(email)
-			return false
 		else
 			return true
 
@@ -47,7 +41,7 @@ module.exports = UserRegistrationHandler =
 		requestIsValid = @_registrationRequestIsValid userDetails
 		if !requestIsValid
 			return callback(new Error("request is not valid"))
-		userDetails.email = userDetails.email?.trim()?.toLowerCase()
+		userDetails.email = EmailHelper.parseEmail(userDetails.email)
 		UserGetter.getUserByAnyEmail userDetails.email, (err, user) =>
 			if err?
 				return callback err

services/web/package.json

@@ -62,7 +62,6 @@
     "marked": "^0.3.5",
     "method-override": "^2.3.3",
     "metrics-sharelatex": "git+https://github.com/sharelatex/metrics-sharelatex.git#v1.7.1",
-    "mimelib": "0.2.14",
     "mocha": "^5.0.1",
     "mongojs": "2.4.0",
     "mongoose": "4.11.4",

services/web/test/unit/coffee/User/UserRegistrationHandlerTests.coffee

@@ -5,6 +5,7 @@ path = require('path')
 modulePath = path.join __dirname, '../../../../app/js/Features/User/UserRegistrationHandler'
 sinon = require("sinon")
 expect = require("chai").expect
+EmailHelper = require '../../../../app/js/Features/Helpers/EmailHelper'
 
 describe "UserRegistrationHandler", ->
 
@@ -37,6 +38,7 @@ describe "UserRegistrationHandler", ->
 			"../Security/OneTimeTokenHandler": @OneTimeTokenHandler
 			"../Analytics/AnalyticsManager": @AnalyticsManager = { recordEvent: sinon.stub() }
 			"settings-sharelatex": @settings = {siteUrl: "http://sl.example.com"}
+			"../Helpers/EmailHelper": EmailHelper
 
 		@passingRequest = {email:"something@email.com", password:"123"}