lib: fix multiple calls of callback in connect

This fixes bug introduced in #281.

PR-URL: #293
Reviewed-By: Dmytro Nechai <nechaido@gmail.com>
Reviewed-By: Denys Otrishko <shishugi@gmail.com>

lib/socket.js

@@ -86,15 +86,16 @@ const socketFactory = (connect) => {
   const resultConnectFn = (...options) => {
     const callback = common.extractCallback(options);
     const socket = connect(...options);
-    socket.once('error', (error) => {
+    const onceErrorListener = (error) => {
       if (error.code !== 'EAGAIN') {
         callback(error);
         return;
       }
       process.nextTick(resultConnectFn, ...options, callback);
-    });
+    };
+    socket.once('error', onceErrorListener);
     socket.once('connect', () => {
-      socket.removeListener('error', callback);
+      socket.removeListener('error', onceErrorListener);
       callback(null, socket);
     });
   };

test/node/connection-callback-multiple-calls.js

@@ -0,0 +1,41 @@
+'use strict';
+
+const test = require('tap');
+const jstp = require('../..');
+
+const app = new jstp.Application('app', {});
+
+let server;
+
+test.beforeEach((done) => {
+  server = jstp.net.createServer({ applications: [app] });
+  server.listen(0, done);
+});
+
+test.afterEach((done) => {
+  server.close(done);
+});
+
+test.test('must call connect callback once on successful connect', (test) => {
+  test.plan(1);
+  const port = server.address().port;
+  jstp.net.connect(app.name, null, port, (error, connection) => {
+    test.assertNot(error, 'must not return error');
+    connection.getTransport().destroy();
+    connection.on('error', () => {
+      // dismiss
+    });
+    connection.emitRemoteEvent('someService', 'someEvent', []);
+  });
+});
+
+const invalidAddress = {
+  host: '__invalid_host__',
+};
+
+test.test('must call connect callback once on error on connect', (test) => {
+  test.plan(1);
+  jstp.net.connect(app.name, null, invalidAddress, (error) => {
+    test.assert(error, 'must return error');
+  });
+});