Improve test coverage for CiVis classes (#11768)

fix: ExecutionAggregation coverage

fix: TestExecutionPolicy coverage

Co-authored-by: devflow.devflow-routing-intake <devflow.devflow-routing-intake@kubernetes.us1.ddbuild.io>

Author: daniel-mohedano

internal-api/build.gradle.kts

@@ -197,6 +197,7 @@ extra["excludedClassesCoverage"] = listOf(
   "datadog.trace.api.cache.FixedSizeCache.IdentityHash",
   "datadog.trace.api.cache.FixedSizeWeakKeyCache",
   // Interface with default method
+  "datadog.trace.api.civisibility.execution.TestExecutionPolicy",
   "datadog.trace.api.iast.Taintable",
   "datadog.trace.api.Stateful",
   "datadog.trace.api.Stateful.1",

internal-api/src/test/java/datadog/trace/api/civisibility/execution/ExecutionAggregationTest.java

@@ -0,0 +1,54 @@
+package datadog.trace.api.civisibility.execution;
+
+import static datadog.trace.api.civisibility.execution.ExecutionAggregation.MIXED;
+import static datadog.trace.api.civisibility.execution.ExecutionAggregation.NONE;
+import static datadog.trace.api.civisibility.execution.ExecutionAggregation.ONLY_FAILED;
+import static datadog.trace.api.civisibility.execution.ExecutionAggregation.ONLY_PASSED;
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+import org.junit.jupiter.api.Test;
+
+class ExecutionAggregationTest {
+
+  @Test
+  void noneAfterFailIsOnlyFailed() {
+    assertEquals(ONLY_FAILED, NONE.withExecution(TestStatus.fail));
+  }
+
+  @Test
+  void noneAfterPassIsOnlyPassed() {
+    assertEquals(ONLY_PASSED, NONE.withExecution(TestStatus.pass));
+  }
+
+  @Test
+  void noneAfterSkipIsOnlyPassed() {
+    assertEquals(ONLY_PASSED, NONE.withExecution(TestStatus.skip));
+  }
+
+  @Test
+  void onlyFailedAfterFailStaysOnlyFailed() {
+    assertEquals(ONLY_FAILED, ONLY_FAILED.withExecution(TestStatus.fail));
+  }
+
+  @Test
+  void onlyFailedAfterPassIsMixed() {
+    assertEquals(MIXED, ONLY_FAILED.withExecution(TestStatus.pass));
+  }
+
+  @Test
+  void onlyPassedAfterPassStaysOnlyPassed() {
+    assertEquals(ONLY_PASSED, ONLY_PASSED.withExecution(TestStatus.pass));
+  }
+
+  @Test
+  void onlyPassedAfterFailIsMixed() {
+    assertEquals(MIXED, ONLY_PASSED.withExecution(TestStatus.fail));
+  }
+
+  @Test
+  void mixedAfterAnyStatusStaysMixed() {
+    assertEquals(MIXED, MIXED.withExecution(TestStatus.pass));
+    assertEquals(MIXED, MIXED.withExecution(TestStatus.fail));
+    assertEquals(MIXED, MIXED.withExecution(TestStatus.skip));
+  }
+}