tls: validate 'as' option using validateOneOf

Author: haramj

lib/tls.js

@@ -60,7 +60,10 @@ const { Buffer } = require('buffer');
 const { canonicalizeIP } = internalBinding('cares_wrap');
 const tlsCommon = require('internal/tls/common');
 const tlsWrap = require('internal/tls/wrap');
-const { validateString } = require('internal/validators');
+const {
+  validateOneOf,
+  validateString,
+} = require('internal/validators');
 const { X509Certificate } = require('crypto');
 
 // Allow {CLIENT_RENEG_LIMIT} client-initiated session renegotiations
@@ -174,6 +177,7 @@ function getCACertificates(options = {}) {
 
   const { type = 'default', as = 'buffer' } = options;
   validateString(type, 'type');
+  validateOneOf(as, 'as', ['buffer', 'x509']);
 
   let certs;
   switch (type) {

test/parallel/test-tls-get-ca-certificates-x509-option.js

@@ -19,4 +19,3 @@ function testX509Option() {
 }
 
 testX509Option();
-