HystrixThreadPoolMetrics.getRollingCountThreadsExecuted() always retu…

…rns 0 in 1.4.x - failing test case

hystrix-core/src/main/java/com/netflix/hystrix/HystrixThreadPoolMetrics.java

@@ -90,6 +90,10 @@ public static Collection<HystrixThreadPoolMetrics> getInstances() {
         return Collections.unmodifiableCollection(metrics.values());
     }
 
+    public static void resetAll() {
+        metrics.clear();
+    }
+
     private final HystrixThreadPoolKey threadPoolKey;
     private final HystrixRollingNumber counter;
     private final ThreadPoolExecutor threadPool;

hystrix-core/src/test/java/com/netflix/hystrix/HystrixThreadPoolMetricsTest.java

@@ -0,0 +1,53 @@
+package com.netflix.hystrix;
+
+import org.junit.After;
+import org.junit.Test;
+
+import java.util.Collection;
+
+import static org.junit.Assert.assertEquals;
+
+public class HystrixThreadPoolMetricsTest {
+
+	@After
+	public void resetAll() {
+		HystrixThreadPoolMetrics.resetAll();
+	}
+
+	@Test
+	public void shouldYieldNoExecutedTasksOnStartup() throws Exception {
+		//given
+		final Collection<HystrixThreadPoolMetrics> instances = HystrixThreadPoolMetrics.getInstances();
+
+		//then
+		assertEquals(0, instances.size());
+
+	}
+	@Test
+	public void shouldReturnOneExecutedTask() throws Exception {
+		//given
+		final Collection<HystrixThreadPoolMetrics> instances = HystrixThreadPoolMetrics.getInstances();
+
+		//when
+		new NoOpHystrixCommand().execute();
+
+		//then
+		assertEquals(1, instances.size());
+		assertEquals(1, instances.iterator().next().getRollingCountThreadsExecuted());
+	}
+
+	private static class NoOpHystrixCommand extends HystrixCommand<Void> {
+		public NoOpHystrixCommand() {
+			super(
+					Setter.withGroupKey(
+							HystrixCommandGroupKey.Factory.asKey("HystrixThreadPoolMetrics-UnitTest")));
+		}
+
+		@Override
+		protected Void run() throws Exception {
+			return null;
+		}
+	}
+
+
+}