instant.put
            userInputReader.putInput(response)
        }
        instant.read > instant.put

        where:
        response << [
            new UserInputReader.TextResponse("answer"),
            UserInputReader.END_OF_INPUT
        ]
    }

    def "does not block after end of input received"() {
        given:
        userInputReader.putInput(UserInputReader.END_OF_INPUT)

        expect:

                inputReader.putInput(new UserInputReader.TextResponse(input.getResponse()));
            }

            @Override
            public void onEndOfInput() {
                LOGGER.debug("Closing this process' stdin at end of input.");
                try {
                    stdInStream.close();
                    inputReader.putInput(UserInputReader.END_OF_INPUT);
                } finally {

    @Override
    public void startInput() {
        synchronized (lock) {
            pending = null;
            finished = false;
        }
    }

    @Override
    public void putInput(UserInput input) {
        synchronized (lock) {
            if (input == END_OF_INPUT) {
                finished = true;
                lock.notifyAll();
            } else {
                if (pending != null) {

 */
@ServiceScope(Scope.Global.class)
public interface UserInputReader {
    /**
     * Called when the current process starts receiving user input from the client.
     */
    void startInput();

    void putInput(UserInput input);

    /**
     * Returns a {@link TextResponse} containing text supplied by the user, or {@link #END_OF_INPUT} if interrupted.
     */
    UserInput readInput();

    abstract class UserInput {