            let runTest = function (socket) {
                let client = new SMTPConnection({
                    logger: false,
                    port: PORT_NUMBER,
                    connection: socket
                });

                client.connect(function () {
                    expect(client.secure).to.be.true;
                    client.login(
                        {
                            user: 'testuser',
                            credentials: {
                                user: 'testuser',
                                pass: 'testpass'
                            }
                        },
                        function (err) {
                            expect(err).to.not.exist;
                            expect(client.authenticated).to.be.true;
                            client.close();
                        }
                    );
                });

                client.on('error', function (err) {
                    expect(err).to.not.exist;
                });

                client.on('end', done);
            };
The software constructs a string for a command to executed by a separate component
in another control sphere, but it does not properly delimit the
intended arguments, options, or switches within that command string.