### Question:
ExtraFieldPropagation implements Propagation<K> { @Deprecated public static void set(String name, String value) { BaggageField field = BaggageField.getByName(validateFieldName(name)); if (field == null) return; field.updateValue(value); } ExtraFieldPropagation(Propagation<K> delegate, List<K> extraKeys); @Deprecated static Factory newFactory(Propagation.Factory delegate, String... names); @Deprecated static Factory newFactory(Propagation.Factory delegate,
    Collection<String> names); @Deprecated static FactoryBuilder newFactoryBuilder(Propagation.Factory delegate); @Deprecated @Nullable static String current(String name); @Deprecated @Nullable static String get(String name); @Deprecated static void set(String name, String value); @Deprecated static Map<String, String> getAll(); @Deprecated static Map<String, String> getAll(TraceContextOrSamplingFlags extracted); @Deprecated static Map<String, String> getAll(TraceContext context); @Deprecated @Nullable static String get(TraceContext context, String name); @Deprecated static void set(TraceContext context, String name, String value); @Deprecated List<K> extraKeys(); @Override List<K> keys(); @Override Injector<R> injector(Setter<R, K> setter); @Override Extractor<R> extractor(Getter<R, K> getter);  }### Answer:
@Test public void current_set_noop_if_no_current_context() { try (Tracing t = Tracing.newBuilder().propagationFactory(factory).build()) { ExtraFieldPropagation.set("x-amzn-trace-id", awsTraceId); } }
@Test public void current_set_noop_if_nothing_current() { ExtraFieldPropagation.set("x-amzn-trace-id", awsTraceId); }