diff --git a/wear/src/test/java/info/nightscout/androidaps/testing/utils/BasalWatchDataExt.java b/wear/src/test/java/info/nightscout/androidaps/testing/utils/BasalWatchDataExt.java
index 0739e8ac9d..9a23f491d9 100644
--- a/wear/src/test/java/info/nightscout/androidaps/testing/utils/BasalWatchDataExt.java
+++ b/wear/src/test/java/info/nightscout/androidaps/testing/utils/BasalWatchDataExt.java
@@ -2,16 +2,11 @@ package info.nightscout.androidaps.testing.utils;
 
 import androidx.annotation.Nullable;
 
-import java.lang.reflect.Field;
-import java.util.Arrays;
-import java.util.HashSet;
 import java.util.Objects;
-import java.util.Set;
 
 import info.nightscout.androidaps.data.BasalWatchData;
 
-import static org.hamcrest.CoreMatchers.is;
-import static org.junit.Assert.assertThat;
+import static info.nightscout.androidaps.testing.utils.ExtUtil.assertClassHaveSameFields;
 
 public class BasalWatchDataExt extends BasalWatchData {
 
@@ -22,16 +17,9 @@ public class BasalWatchDataExt extends BasalWatchData {
     public BasalWatchDataExt(BasalWatchData ref) {
         super();
 
-        Set<String> parentFields = new HashSet<>();
-        for (Field f : BasalWatchData.class.getDeclaredFields()) {
-            parentFields.add(f.getName());
-        }
-
-        Set<String> knownFields = new HashSet<>(Arrays.asList("startTime,endTime,amount".split(",")));
-
         // since we do not want modify BasalWatchData - we use this wrapper class
         // but we make sure it has same fields
-        assertThat(parentFields, is(knownFields));
+        assertClassHaveSameFields(BasalWatchData.class, "startTime,endTime,amount");
 
         this.startTime = ref.startTime;
         this.endTime = ref.endTime;
diff --git a/wear/src/test/java/info/nightscout/androidaps/testing/utils/BgWatchDataExt.java b/wear/src/test/java/info/nightscout/androidaps/testing/utils/BgWatchDataExt.java
index 0c1d4a0bf3..c49125809e 100644
--- a/wear/src/test/java/info/nightscout/androidaps/testing/utils/BgWatchDataExt.java
+++ b/wear/src/test/java/info/nightscout/androidaps/testing/utils/BgWatchDataExt.java
@@ -2,16 +2,11 @@ package info.nightscout.androidaps.testing.utils;
 
 import androidx.annotation.Nullable;
 
-import java.lang.reflect.Field;
-import java.util.Arrays;
-import java.util.HashSet;
 import java.util.Objects;
-import java.util.Set;
 
 import info.nightscout.androidaps.data.BgWatchData;
 
-import static org.hamcrest.CoreMatchers.is;
-import static org.junit.Assert.assertThat;
+import static info.nightscout.androidaps.testing.utils.ExtUtil.assertClassHaveSameFields;
 
 public class BgWatchDataExt extends BgWatchData {
 
@@ -26,16 +21,9 @@ public class BgWatchDataExt extends BgWatchData {
     public BgWatchDataExt(BgWatchData ref) {
         super();
 
-        Set<String> parentFields = new HashSet<>();
-        for (Field f : BgWatchData.class.getDeclaredFields()) {
-            parentFields.add(f.getName());
-        }
-
-        Set<String> knownFields = new HashSet<>(Arrays.asList("sgv,high,low,timestamp,color".split(",")));
-
         // since we do not want modify BgWatchDataExt - we use this wrapper class
         // but we make sure it has same fields
-        assertThat(parentFields, is(knownFields));
+        assertClassHaveSameFields(BgWatchData.class, "sgv,high,low,timestamp,color");
 
         this.sgv = ref.sgv;
         this.high = ref.high;
diff --git a/wear/src/test/java/info/nightscout/androidaps/testing/utils/BolusWatchDataExt.java b/wear/src/test/java/info/nightscout/androidaps/testing/utils/BolusWatchDataExt.java
index 13e6f52f8f..a5553f6a59 100644
--- a/wear/src/test/java/info/nightscout/androidaps/testing/utils/BolusWatchDataExt.java
+++ b/wear/src/test/java/info/nightscout/androidaps/testing/utils/BolusWatchDataExt.java
@@ -2,16 +2,11 @@ package info.nightscout.androidaps.testing.utils;
 
 import androidx.annotation.Nullable;
 
-import java.lang.reflect.Field;
-import java.util.Arrays;
-import java.util.HashSet;
 import java.util.Objects;
-import java.util.Set;
 
 import info.nightscout.androidaps.data.BolusWatchData;
 
-import static org.hamcrest.CoreMatchers.is;
-import static org.junit.Assert.assertThat;
+import static info.nightscout.androidaps.testing.utils.ExtUtil.assertClassHaveSameFields;
 
 public class BolusWatchDataExt extends BolusWatchData {
 
@@ -22,16 +17,9 @@ public class BolusWatchDataExt extends BolusWatchData {
     public BolusWatchDataExt(BolusWatchData ref) {
         super();
 
-        Set<String> parentFields = new HashSet<>();
-        for (Field f : BolusWatchData.class.getDeclaredFields()) {
-            parentFields.add(f.getName());
-        }
-
-        Set<String> knownFields = new HashSet<>(Arrays.asList("date,bolus,carbs,isSMB,isValid".split(",")));
-
         // since we do not want modify BolusWatchData - we use this wrapper class
         // but we make sure it has same fields
-        assertThat(parentFields, is(knownFields));
+        assertClassHaveSameFields(BolusWatchData.class, "date,bolus,carbs,isSMB,isValid");
 
         this.date = ref.date;
         this.bolus = ref.bolus;
diff --git a/wear/src/test/java/info/nightscout/androidaps/testing/utils/ExtUtil.java b/wear/src/test/java/info/nightscout/androidaps/testing/utils/ExtUtil.java
new file mode 100644
index 0000000000..1559db11ae
--- /dev/null
+++ b/wear/src/test/java/info/nightscout/androidaps/testing/utils/ExtUtil.java
@@ -0,0 +1,28 @@
+package info.nightscout.androidaps.testing.utils;
+
+import java.lang.reflect.Field;
+import java.util.Arrays;
+import java.util.HashSet;
+import java.util.Set;
+
+import static org.hamcrest.CoreMatchers.is;
+import static org.junit.Assert.assertThat;
+
+class ExtUtil {
+
+    static <T> void  assertClassHaveSameFields(Class<T> checkedClass, String commaSeparatedFieldList) {
+        Set<String> parentFields = new HashSet<>();
+        for (Field f : checkedClass.getDeclaredFields()) {
+            final String fieldName = f.getName();
+            // skip runtime-injected fields like $jacocoData
+            if (fieldName.startsWith("$")) {
+                continue;
+            }
+            parentFields.add(fieldName);
+        }
+
+        Set<String> knownFields = new HashSet<>(Arrays.asList(commaSeparatedFieldList.split(",")));
+        assertThat(parentFields, is(knownFields));
+    }
+
+}
diff --git a/wear/src/test/java/info/nightscout/androidaps/testing/utils/TempWatchDataExt.java b/wear/src/test/java/info/nightscout/androidaps/testing/utils/TempWatchDataExt.java
index 171d8ac841..478c6de966 100644
--- a/wear/src/test/java/info/nightscout/androidaps/testing/utils/TempWatchDataExt.java
+++ b/wear/src/test/java/info/nightscout/androidaps/testing/utils/TempWatchDataExt.java
@@ -2,16 +2,11 @@ package info.nightscout.androidaps.testing.utils;
 
 import androidx.annotation.Nullable;
 
-import java.lang.reflect.Field;
-import java.util.Arrays;
-import java.util.HashSet;
 import java.util.Objects;
-import java.util.Set;
 
 import info.nightscout.androidaps.data.TempWatchData;
 
-import static org.hamcrest.CoreMatchers.is;
-import static org.junit.Assert.assertThat;
+import static info.nightscout.androidaps.testing.utils.ExtUtil.assertClassHaveSameFields;
 
 
 public class TempWatchDataExt extends TempWatchData {
@@ -23,16 +18,9 @@ public class TempWatchDataExt extends TempWatchData {
     public TempWatchDataExt(TempWatchData ref) {
         super();
 
-        Set<String> parentFields = new HashSet<>();
-        for (Field f : TempWatchData.class.getDeclaredFields()) {
-            parentFields.add(f.getName());
-        }
-
-        Set<String> knownFields = new HashSet<>(Arrays.asList("startTime,startBasal,endTime,endBasal,amount".split(",")));
-
-        // since we do not want modify TempWatchData - we use this wrapper class
+        // since we do not want modify BolusWatchData - we use this wrapper class
         // but we make sure it has same fields
-        assertThat(parentFields, is(knownFields));
+        assertClassHaveSameFields(TempWatchData.class, "startTime,startBasal,endTime,endBasal,amount");
 
         this.startTime = ref.startTime;
         this.startBasal = ref.startBasal;