Add test for failed poll scenario

See gh-2549

implementations/micrometer-registry-statsd/src/test/java/io/micrometer/statsd/StatsdMeterRegistryTest.java

@@ -44,8 +44,7 @@
 
 import static java.util.Collections.singletonList;
 import static java.util.stream.IntStream.range;
-import static org.assertj.core.api.Assertions.assertThat;
-import static org.assertj.core.api.Assertions.fail;
+import static org.assertj.core.api.Assertions.*;
 
 /**
  * Tests for {@link StatsdMeterRegistry}.
@@ -543,6 +542,17 @@ void stopTrackingMetersThatAreRemoved() {
         assertThat(lines.get("functioncounter")).isEqualTo(1);
     }
 
+    @Test
+    void pollFailureNotFatal() {
+        registry = StatsdMeterRegistry.builder(StatsdConfig.DEFAULT).build();
+        Gauge.builder("fails", "", o -> {
+            throw new RuntimeException();
+        }).register(registry);
+        Gauge.builder("works", () -> 42).register(registry);
+
+        assertThatCode(() -> registry.poll()).doesNotThrowAnyException();
+    }
+
     private UnicastProcessor<String> lineProcessor() {
         return UnicastProcessor.create(Queues.<String>unboundedMultiproducer().get());
     }