1 files changed, 14 insertions, 0 deletions
diff --git a/src/test/java/org/apache/commons/lang3/time/DurationUtilsTest.java b/src/test/java/org/apache/commons/lang3/time/DurationUtilsTest.java
index 89023e9b6..d3d8f3126 100644
--- a/src/test/java/org/apache/commons/lang3/time/DurationUtilsTest.java
+++ b/src/test/java/org/apache/commons/lang3/time/DurationUtilsTest.java
@@ -38,6 +38,20 @@ public class DurationUtilsTest extends AbstractLangTest {
 
     @Test
     public void testGetNanosOfMilli() {
+        assertEquals(0, DurationUtils.getNanosOfMilli(null));
+        assertEquals(0, DurationUtils.getNanosOfMilli(Duration.ZERO));
+        assertEquals(1, DurationUtils.getNanosOfMilli(Duration.ofNanos(1)));
+        assertEquals(10, DurationUtils.getNanosOfMilli(Duration.ofNanos(10)));
+        assertEquals(100, DurationUtils.getNanosOfMilli(Duration.ofNanos(100)));
+        assertEquals(1_000, DurationUtils.getNanosOfMilli(Duration.ofNanos(1_000)));
+        assertEquals(10_000, DurationUtils.getNanosOfMilli(Duration.ofNanos(10_000)));
+        assertEquals(100_000, DurationUtils.getNanosOfMilli(Duration.ofNanos(100_000)));
+        assertEquals(0, DurationUtils.getNanosOfMilli(Duration.ofNanos(1_000_000)));
+        assertEquals(1, DurationUtils.getNanosOfMilli(Duration.ofNanos(1_000_001)));
+    }
+
+    @Test
+    public void testGetNanosOfMiili() {
         assertEquals(0, DurationUtils.getNanosOfMiili(null));
         assertEquals(0, DurationUtils.getNanosOfMiili(Duration.ZERO));
         assertEquals(1, DurationUtils.getNanosOfMiili(Duration.ofNanos(1)));