test: fix test failure due to localhost being also ipv6

Depending on runtime environment, "localhost" might resolve to both IPv4 and IPv6, resulting in an AggregateError in place of an Error.

Author: ikonst

test/supertest.js

@@ -34,7 +34,7 @@ describe('request(url)', function () {
     });
 
     server = app.listen(function () {
-      const url = 'http://localhost:' + server.address().port;
+      const url = 'http://127.0.0.1:' + server.address().port;
       request(url)
         .get('/')
         .expect('hello', done);
@@ -51,7 +51,7 @@ describe('request(url)', function () {
       });
 
       server = app.listen(function () {
-        const url = 'http://localhost:' + server.address().port;
+        const url = 'http://127.0.0.1:' + server.address().port;
         const test = request(url).get('/');
         test.end(function (err, res) {
           this.should.eql(test);
@@ -107,7 +107,7 @@ describe('request(app)', function () {
     });
 
     server = app.listen(function () {
-      const url = 'http://localhost:' + server.address().port;
+      const url = 'http://127.0.0.1:' + server.address().port;
       request(url)
         .get('/')
         .end(function (err, res) {
@@ -328,7 +328,7 @@ describe('request(app)', function () {
       });
 
       server = app.listen(function () {
-        const url = 'http://localhost:' + server.address().port;
+        const url = 'http://127.0.0.1:' + server.address().port;
         request(url)
           .get('/')
           .timeout(1)
@@ -348,7 +348,7 @@ describe('request(app)', function () {
       });
 
       server = app.listen(function () {
-        const url = 'http://localhost:' + server.address().port;
+        const url = 'http://127.0.0.1:' + server.address().port;
         server.close();
         request(url)
           .get('/')
@@ -381,7 +381,7 @@ describe('request(app)', function () {
 
   describe('.expect(status)', function () {
     it('should handle connection error', function (done) {
-      const req = request.agent('http://localhost:1234');
+      const req = request.agent('http://127.0.0.1:1234');
 
       req
         .get('/')