fix: allow hostname ports without protocol

src/lib/isURL.js

@@ -103,6 +103,23 @@ export default function isURL(url, options) {
     return url.substring(protocol_match[0].length);
   };
 
+  const isHostWithPort = (potential_host, potential_port) => {
+    if (options.require_protocol || !/^[0-9]+$/.test(potential_port)) {
+      return false;
+    }
+
+    const port_number = parseInt(potential_port, 10);
+    if (port_number <= 0 || port_number > 65535) {
+      return false;
+    }
+
+    if (isIP(potential_host) || isFQDN(potential_host, options)) {
+      return true;
+    }
+
+    return options.host_whitelist ? checkHost(potential_host, options.host_whitelist) : false;
+  };
+
   if (protocol_match) {
     const potential_protocol = protocol_match[1];
     const after_colon = url.substring(protocol_match[0].length);
@@ -141,8 +158,8 @@ export default function isURL(url, options) {
             return false;
           }
         }
-      } else {
-        // No @ symbol, this is definitely a protocol
+      } else if (!isHostWithPort(potential_protocol, before_slash)) {
+        // No @ symbol and not a hostname with a numeric port, so treat it as a protocol.
         url = cleanUpProtocol(potential_protocol);
 
         if (url === false) {

test/validators.test.js

@@ -499,6 +499,7 @@ describe('Validators', () => {
         'localhost',
         'localhost:3000',
         'service-name:8080',
+        'my-3272-service:9000',
         'https://localhost',
         'http://localhost:3000',
         'http://service-name:8080',