encoder.writeSmallLong(value.getFromVariant());
        if (value.getFailure() == null) {
            if (value.getSelectedVariant() != null) {
                encoder.writeByte(SUCCESSFUL);
                encoder.writeSmallLong(value.getSelected());
                encoder.writeSmallLong(value.getSelectedVariant());
            } else {
                encoder.writeByte(SUCCESSFUL_NOTHING_SELECTED);

     */
    Long getFromVariant();

    /**
     * Returns the simple id of the selected variant, as per {@link ResolvedGraphVariant#getNodeId()}.
     */
    @Nullable
    Long getSelectedVariant();

                if (d.getSelectedVariant() != null) {
                    selectedVariant = selectedComponent.getVariant(d.getSelectedVariant());
                    if (selectedVariant == null) {

                getResultId() >> 4L
                getRequested() >> requested
            }
            getFromVariant() >> 55L
            getFailure() >> null
            getSelected() >> 12L
            getSelectedVariant() >> 123L
            getReason() >> ComponentSelectionReasons.requested()
        }

        when:
        def bytes = new ByteArrayOutputStream()
        def encoder = new OutputStreamBackedEncoder(bytes)

    public boolean isConstraint() {
        return constraint;
    }

    @Override
    public Long getFromVariant() {
        return fromVariant;
    }

    @Override
    public Long getSelectedVariant() {
        return targetVariant;
    }

        return Stub(ResolvedGraphDependency) {
            getRequested() >> selector
            getFromVariant() >> id(from)
            getSelected() >> id(selected)
            getSelectedVariant() >> id(selected)
            getFailure() >> failure
        }
    }

    private Long id(String module) {
        return module.hashCode()
    }

    }

    boolean hasSelectedVariant() {
        return resolvedVariant != null || !findTargetNodes().isEmpty();
    }

    @Nullable
    @Override
    public Long getSelectedVariant() {
        NodeState node = getSelectedNode();
        if (node == null) {
            return null;
        } else {
            return node.getNodeId();
        }
    }

    @Nullable