test: add test for addDimension exception

Author: surajkumar

src/main/java/uk/gov/di/ipv/cri/common/library/util/EventProbe.java

@@ -87,7 +87,7 @@ public EventProbe addJourneyIdToLoggingContext(String journeyId) {
 
     public void addDimensions(Map<String, String> dimensions) {
         if (dimensions != null) {
-            DimensionSet dimensionSet = new DimensionSet();
+            DimensionSet dimensionSet = newDimensionSet();
             dimensions.forEach(
                     (key, value) -> {
                         try {
@@ -165,4 +165,8 @@ private static String removePrefixedColons(String value) {
     private static boolean isAsciiPrintable(final char ch) {
         return ch >= 32 && ch < 127;
     }
+
+    public DimensionSet newDimensionSet() {
+        return new DimensionSet();
+    }
 }

src/test/java/uk/gov/di/ipv/cri/common/library/util/EventProbeTest.java

@@ -30,8 +30,12 @@
 import static org.junit.jupiter.api.Assertions.assertSame;
 import static org.junit.jupiter.api.Assertions.assertTrue;
 import static org.mockito.ArgumentMatchers.any;
+import static org.mockito.ArgumentMatchers.anyString;
+import static org.mockito.Mockito.doReturn;
 import static org.mockito.Mockito.doThrow;
+import static org.mockito.Mockito.mock;
 import static org.mockito.Mockito.never;
+import static org.mockito.Mockito.spy;
 import static org.mockito.Mockito.verify;
 
 @ExtendWith(MockitoExtension.class)
@@ -263,4 +267,22 @@ void counterMetricWithValueHandlesExceptionGracefully() {
         verify(mockMetrics).addMetric("bad-metric-2", 42d);
         assertSame(eventProbe, result);
     }
+
+    @Test
+    void addDimensionsHandlesExceptionsGracefully() {
+        DimensionSet mockSet = mock(DimensionSet.class);
+
+        doThrow(new RuntimeException("error")).when(mockSet).addDimension(anyString(), anyString());
+
+        EventProbe spyProbe = spy(new EventProbe(mockMetrics));
+        doReturn(mockSet).when(spyProbe).newDimensionSet();
+
+        doThrow(new RuntimeException("error"))
+                .when(mockMetrics)
+                .addDimension(any(DimensionSet.class));
+
+        assertDoesNotThrow(() -> spyProbe.addDimensions(Map.of("bad Key", "bad Value")));
+
+        verify(mockMetrics).addDimension(mockSet);
+    }
 }