Fix division-by-zero error in Persistence average (openhab#3556)

* Fix division-by-zero error in Persistence average * Add test Signed-off-by: Jimmy Tanagra <jcode@tanagra.id.au> GitOrigin-RevId: 7a9b76d
ConnectorIO · Jul 12, 2023 · 6aaaef7 · 6aaaef7
1 parent 2947189
commit 6aaaef7
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diff --git a/...sistence/src/main/java/org/openhab/core/persistence/extensions/PersistenceExtensions.java b/...sistence/src/main/java/org/openhab/core/persistence/extensions/PersistenceExtensions.java
@@ -824,7 +824,8 @@ public static boolean updatedBetween(Item item, ZonedDateTime begin, ZonedDateTi
 
         if (firstTimestamp != null) {
             BigDecimal totalDuration = BigDecimal.valueOf(Duration.between(firstTimestamp, endTime).toMillis());
-            return new DecimalType(sum.divide(totalDuration, MathContext.DECIMAL64));
+            return totalDuration.signum() == 0 ? null
+                    : new DecimalType(sum.divide(totalDuration, MathContext.DECIMAL64));
         }
 
         return null;

diff --git a/...ence/src/test/java/org/openhab/core/persistence/extensions/PersistenceExtensionsTest.java b/...ence/src/test/java/org/openhab/core/persistence/extensions/PersistenceExtensionsTest.java
@@ -18,6 +18,7 @@
 import static org.hamcrest.CoreMatchers.nullValue;
 import static org.hamcrest.MatcherAssert.assertThat;
 import static org.hamcrest.Matchers.closeTo;
+import static org.junit.jupiter.api.Assertions.assertDoesNotThrow;
 import static org.junit.jupiter.api.Assertions.assertEquals;
 import static org.junit.jupiter.api.Assertions.assertFalse;
 import static org.junit.jupiter.api.Assertions.assertNotNull;
@@ -680,6 +681,15 @@ public void testAverageSinceSwitch() {
         assertThat(average, is(nullValue()));
     }
 
+    @Test
+    public void testAverageBetweenZeroDuration() {
+        ZonedDateTime now = ZonedDateTime.now();
+        assertDoesNotThrow(
+                () -> PersistenceExtensions.averageBetween(quantityItem, now, now, TestPersistenceService.ID));
+        assertThat(PersistenceExtensions.averageBetween(quantityItem, now, now, TestPersistenceService.ID),
+                is(nullValue()));
+    }
+
     @Test
     public void testSumSinceDecimalType() {
         DecimalType sum = PersistenceExtensions.sumSince(numberItem,