From c9835660f92278e819db56dbea82ab29b8d0653f Mon Sep 17 00:00:00 2001
From: Yun-Ting <yunl@microsoft.com>
Date: Fri, 24 Mar 2023 12:05:29 -0700
Subject: [PATCH] test

---
 .../OtlpTraceExporterTests.cs                 | 26 +++++++++++++++++++
 1 file changed, 26 insertions(+)

diff --git a/test/OpenTelemetry.Exporter.OpenTelemetryProtocol.Tests/OtlpTraceExporterTests.cs b/test/OpenTelemetry.Exporter.OpenTelemetryProtocol.Tests/OtlpTraceExporterTests.cs
index a3003baf8a7..0dda7611a59 100644
--- a/test/OpenTelemetry.Exporter.OpenTelemetryProtocol.Tests/OtlpTraceExporterTests.cs
+++ b/test/OpenTelemetry.Exporter.OpenTelemetryProtocol.Tests/OtlpTraceExporterTests.cs
@@ -551,6 +551,32 @@ public void ToOtlpSpanActivityStatusTakesPrecedenceOverStatusTagsWhenActivitySta
             Assert.Equal(StatusDescriptionOnError, otlpSpan.Status.Message);
         }
 
+        [Theory]
+        [InlineData(true)]
+        [InlineData(false)]
+        public void ToOtlpSpanTraceStateTest(bool traceStateWasSet)
+        {
+            using var activitySource = new ActivitySource(nameof(this.ToOtlpSpanTest));
+            using var activity = activitySource.StartActivity("Name");
+            string tracestate = "a=b;c=d";
+            if (traceStateWasSet)
+            {
+                activity.TraceStateString = tracestate;
+            }
+
+            var otlpSpan = activity.ToOtlpSpan(DefaultSdkLimitOptions);
+
+            if (traceStateWasSet)
+            {
+                Assert.NotNull(otlpSpan.TraceState);
+                Assert.Equal(tracestate, otlpSpan.TraceState);
+            }
+            else
+            {
+                Assert.True(string.IsNullOrEmpty(otlpSpan.TraceState));
+            }
+        }
+
         [Fact]
         public void ToOtlpSpanPeerServiceTest()
         {