event bus testcase

Author: xiangtianyu

instrumentation/guava-10.0/javaagent/src/test/java/io/opentelemetry/javaagent/instrumentation/guava/v10_0/AsyncEventBusTest.java

@@ -3,32 +3,56 @@
 import com.google.common.eventbus.AsyncEventBus;
 import com.google.common.eventbus.Subscribe;
 import io.opentelemetry.api.trace.Span;
+import io.opentelemetry.instrumentation.testing.junit.AgentInstrumentationExtension;
+import io.opentelemetry.instrumentation.testing.junit.InstrumentationExtension;
 import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.RegisterExtension;
 import java.util.concurrent.ExecutorService;
 import java.util.concurrent.Executors;
 
 import static org.assertj.core.api.Assertions.assertThat;
 
 public class AsyncEventBusTest {
 
+  @RegisterExtension
+  static final InstrumentationExtension testing = AgentInstrumentationExtension.create();
+
   static final ExecutorService executor = Executors.newSingleThreadExecutor();
 
   static final AsyncEventBus asyncEventBus = new AsyncEventBus(executor);
 
   @Test
   void testAsyncEventBusTakeEffect() {
-    String traceId = Span.current().getSpanContext().getTraceId();
+    class Listener {
+      String receivedTraceId;
 
-    class EventListener {
       @Subscribe
-      public void handleEvent(String event) {
-        String eventTraceId = Span.current().getSpanContext().getTraceId();
-        assertThat(eventTraceId).isNotEqualTo("00000000000000000000000000000000");
-        assertThat(eventTraceId).isEqualTo(traceId);
+      public void onEvent(String event) {
+        testing.runWithSpan("listener", () -> {
+          receivedTraceId = Span.current().getSpanContext().getTraceId();
+        });
       }
     }
 
-    asyncEventBus.register(new EventListener());
-    asyncEventBus.post("Hello, AsyncEventBus!");
+    Listener listener = new Listener();
+    asyncEventBus.register(listener);
+
+    String[] parentTraceId = new String[1];
+    testing.runWithSpan("parent", () -> {
+      parentTraceId[0] = Span.current().getSpanContext().getTraceId();
+      asyncEventBus.post("test");
+    });
+
+    testing.waitAndAssertTraces(
+        trace
+            -> trace.hasSpansSatisfyingExactly(
+                span -> span.hasName("parent"),
+            span -> span.hasName("listener")
+        ));
+
+    assertThat(listener.receivedTraceId)
+        .isNotNull()
+        .isNotEqualTo("00000000000000000000000000000000")
+        .isEqualTo(parentTraceId[0]);
   }
 }