1 files changed, 71 insertions, 0 deletions
diff --git a/kamon-core/src/test/scala/kamon/trace/ActiveSpanManagementSpec.scala b/kamon-core/src/test/scala/kamon/trace/ActiveSpanManagementSpec.scala
new file mode 100644
index 00000000..ebee9f66
--- /dev/null
+++ b/kamon-core/src/test/scala/kamon/trace/ActiveSpanManagementSpec.scala
@@ -0,0 +1,71 @@
+package kamon.trace
+
+import kamon.Kamon
+import kamon.testkit.SpanInspector
+import kamon.trace.Span.Annotation
+import kamon.util.Clock
+import org.scalatest.{Matchers, WordSpec}
+
+class ActiveSpanManagementSpec extends WordSpec with Matchers {
+
+  "Kamon acting as a ActiveSpanSource" should {
+    "return a ActiveSpan wrapping a empty span when there is no currently active Span" in {
+      inspect(Kamon.activeSpan()) shouldBe empty
+    }
+
+    "safely operate on a ActiveSpan that wraps a empty Span" in {
+      val activeSpan = Kamon.activeSpan()
+      val activeSpanData = inspect(Kamon.activeSpan())
+      activeSpanData shouldBe empty
+
+      activeSpan
+        .setOperationName("test")
+        .addBaggage("key", "value")
+        .addMetricTag("key", "value")
+        .addSpanTag("string", "string")
+        .addSpanTag("number", 42)
+        .addSpanTag("boolean-true", true)
+        .addSpanTag("boolean-false", false)
+        .annotate(Annotation(Clock.microTimestamp(), "event", Map("k" -> "v")))
+
+      val baggage = activeSpan.context().baggage
+      baggage.add("key", "value")
+      baggage.get("key") shouldBe empty
+      baggage.getAll() shouldBe empty
+
+      val continuation = activeSpan.capture()
+      val activatedSpan = continuation.activate()
+      inspect(Kamon.activeSpan()) shouldBe empty
+      activatedSpan.deactivate()
+
+      inspect(Kamon.activeSpan()) shouldBe empty
+    }
+
+    "set a Span as active when using makeActive" in {
+      val span = Kamon.buildSpan("mySpan").start()
+      val activeSpan = Kamon.makeActive(span)
+      Kamon.activeSpan() shouldBe theSameInstanceAs(activeSpan)
+      activeSpan.deactivate()
+    }
+
+    "set a Span as active when using startActive" in {
+      val activeSpan = Kamon.buildSpan("mySpan").startActive()
+      Kamon.activeSpan() shouldBe theSameInstanceAs(activeSpan)
+      activeSpan.deactivate()
+    }
+
+    "restore the previously active Span when a ActiveSpan gets deactivated" in {
+      val previouslyActiveSpan = Kamon.activeSpan()
+      inspect(Kamon.activeSpan()) shouldBe empty
+
+      val activeSpan = Kamon.buildSpan("mySpan").startActive()
+      Kamon.activeSpan() shouldBe theSameInstanceAs(activeSpan)
+      activeSpan.deactivate()
+
+      Kamon.activeSpan() shouldBe theSameInstanceAs(previouslyActiveSpan)
+    }
+  }
+
+  def inspect(span: Span): SpanInspector =
+    SpanInspector(span)
+}