2 files changed, 10 insertions, 0 deletions
diff --git a/api/src/test/java/io/opencensus/metrics/MetricRegistryTest.java b/api/src/test/java/io/opencensus/metrics/MetricRegistryTest.java
index 0e467dc8..49e8ce02 100644
--- a/api/src/test/java/io/opencensus/metrics/MetricRegistryTest.java
+++ b/api/src/test/java/io/opencensus/metrics/MetricRegistryTest.java
@@ -22,7 +22,11 @@ import java.util.LinkedHashMap;
 import org.junit.Rule;
 import org.junit.Test;
 import org.junit.rules.ExpectedException;
+import org.junit.runner.RunWith;
+import org.junit.runners.JUnit4;
 
+/** Unit tests for {@link MetricRegistry}. */
+@RunWith(JUnit4.class)
 public class MetricRegistryTest {
   @Rule public ExpectedException thrown = ExpectedException.none();
 
diff --git a/api/src/test/java/io/opencensus/metrics/MetricsTest.java b/api/src/test/java/io/opencensus/metrics/MetricsTest.java
index 9a56f257..9e0eee1f 100644
--- a/api/src/test/java/io/opencensus/metrics/MetricsTest.java
+++ b/api/src/test/java/io/opencensus/metrics/MetricsTest.java
@@ -62,4 +62,10 @@ public class MetricsTest {
     assertThat(Metrics.getExportComponent())
         .isInstanceOf(ExportComponent.newNoopExportComponent().getClass());
   }
+
+  @Test
+  public void defaultMetricRegistry() {
+    assertThat(Metrics.getMetricRegistry())
+        .isInstanceOf(MetricRegistry.newNoopMetricRegistry().getClass());
+  }
 }