diff --git a/packages/core/src/lib/compose.js b/packages/core/src/lib/compose.js
index 63dd8aa3f..1816b1dfc 100644
--- a/packages/core/src/lib/compose.js
+++ b/packages/core/src/lib/compose.js
@@ -9,6 +9,7 @@ const parseLink = require('./parseLink');
 const render = require('./render');
 const uikitExcludePattern = require('./uikitExcludePattern');
 const pm = require('./plugin_manager');
+const dataMerger = require('./dataMerger');
 const pluginManager = new pm();
 
 const Pattern = require('./object_factory').Pattern;
@@ -56,8 +57,14 @@ module.exports = async function(pattern, patternlab) {
         'listitems.json + any pattern listitems.json'
       );
 
-      allData = _.merge({}, patternlab.data, pattern.jsonFileData);
-      allData = _.merge({}, allData, allListItems);
+      allData = dataMerger(
+        patternlab.data,
+        pattern.jsonFileData,
+        patternlab.config
+      );
+      // _.merge({}, patternlab.data, pattern.jsonFileData);
+      allData = dataMerger(allData, allListItems, patternlab.config);
+      // _.merge({}, allData, allListItems);
       allData.cacheBuster = patternlab.cacheBuster;
       allData.patternPartial = pattern.patternPartial;
 
diff --git a/packages/core/src/lib/dataMerger.js b/packages/core/src/lib/dataMerger.js
new file mode 100644
index 000000000..5ebdd21bb
--- /dev/null
+++ b/packages/core/src/lib/dataMerger.js
@@ -0,0 +1,32 @@
+const _ = require('lodash');
+
+/**
+ * Merges two objects depending on the configuration and will either merge
+ * arrays and only replaces items on the index or replace the entire
+ * collection of the different parameters
+ *
+ * @param {*} dataObject the object that contains the main data
+ * @param {*} dataToMergeWithObject the object that should be merged with the original data
+ * @param {*} patternlabConfig the patternlab configuration object
+ */
+module.exports = function(dataObject, dataToMergeWithObject, patternlabConfig) {
+  return _.mergeWith(
+    {},
+    dataObject,
+    dataToMergeWithObject,
+    (objValue, srcValue) => {
+      if (
+        _.isArray(objValue) &&
+        // If the parameter is not available after updating pattern lab but
+        // not the patternlab-config it should not override arrays.
+        patternlabConfig.hasOwnProperty('patternMergeVariantArrays') &&
+        !patternlabConfig.patternMergeVariantArrays
+      ) {
+        return srcValue;
+      }
+      // Lodash will only check for "undefined" and eslint needs a consistent
+      // return so do not remove
+      return undefined;
+    }
+  );
+};
diff --git a/packages/core/src/lib/pseudopattern_hunter.js b/packages/core/src/lib/pseudopattern_hunter.js
index 88f1ad646..1d1ee92a3 100644
--- a/packages/core/src/lib/pseudopattern_hunter.js
+++ b/packages/core/src/lib/pseudopattern_hunter.js
@@ -13,6 +13,7 @@ const readDocumentation = require('./readDocumentation');
 const lineage_hunter = new lh();
 const changes_hunter = new ch();
 const yaml = require('js-yaml');
+const dataMerger = require('./dataMerger');
 
 const pseudopattern_hunter = function() {};
 
@@ -60,24 +61,10 @@ pseudopattern_hunter.prototype.find_pseudopatterns = function(
       }
 
       //extend any existing data with variant data
-      variantFileData = _.mergeWith(
-        {},
+      variantFileData = dataMerger(
         currentPattern.jsonFileData,
         variantFileData,
-        (objValue, srcValue) => {
-          if (
-            _.isArray(objValue) &&
-            // If the parameter is not available after updating pattern lab but
-            // not the patternlab-config it should not override arrays.
-            patternlab.config.hasOwnProperty('patternMergeVariantArrays') &&
-            !patternlab.config.patternMergeVariantArrays
-          ) {
-            return srcValue;
-          }
-          // Lodash will only check for "undefined" and eslint needs a consistent
-          // return so do not remove
-          return undefined;
-        }
+        patternlab.config
       );
 
       const variantName = pseudoPatterns[i]