/** Test of extract method, of class AbstractTracer, with an empty carrier. */
@Test
public void testEmptyExtract() {
System.out.println("empty extract");
AbstractTracer instance = new TestTracerImpl();
instance.register(TextMap.class, new TestTextMapExtractorImpl());
Map<String, String> map = Collections.singletonMap("garbageEntry", "garbageVal");
TextMap carrier = new TextMapExtractAdapter(map);
SpanContext emptyResult = instance.extract(Format.Builtin.TEXT_MAP, carrier);
assertNull("Should be nothing to extract", emptyResult);
}
/** Test of extract method, of class AbstractTracer, with a valid carrier. */
@Test
public void testNonEmptyExtract() {
System.out.println("non-empty extract");
AbstractTracer instance = new TestTracerImpl();
instance.register(TextMap.class, new TestTextMapExtractorImpl());
Map<String, String> map = Collections.singletonMap("test-marker", "whatever");
TextMap carrier = new TextMapExtractAdapter(map);
SpanContext result = instance.extract(Format.Builtin.TEXT_MAP, carrier);
assertNotNull("Should be something to extract", result);
assertEquals("Should find the marker", "whatever", ((TestSpanContextImpl) result).getMarker());
}