final Pipe toUser = new Pipe();
final Pipe fromUser = new Pipe();
final String quit = "q";
final String prompt = "Press return to continue, q then return to quit";
final User user = new User( toUser.getReader(), fromUser.getWriter(), quit, prompt);
toUser.writeLine("");
assertTrue(user.wantsToContinue());
assertEquals(prompt, fromUser.readLine());
toUser.writeLine("123");
assertTrue(user.wantsToContinue());
assertEquals(prompt, fromUser.readLine());
toUser.writeLine("123" + quit);
assertTrue(user.wantsToContinue());
assertEquals(prompt, fromUser.readLine());
toUser.writeLine(quit + "1234");
assertTrue(!user.wantsToContinue());
assertEquals(prompt, fromUser.readLine());