[maps] fix More than 2 maps embeddables with geo-shape layers results…

… in empty layers for 3+ (elastic#107442)

* [maps] fix More than 2 maps embeddables with geo-shape layers results in empty layers for 3+

* comment

* add unit test

* eslint

x-pack/plugins/maps/common/elasticsearch_util/elasticsearch_geo_utils.test.js

@@ -269,6 +269,26 @@ describe('hitsToGeoJson', () => {
         type: 'Point',
       });
     });
+
+    it('Should not modify results of flattenHit', () => {
+      const geoFieldName = 'location';
+      const cachedProperities = {
+        [geoFieldName]: '20,100',
+      };
+      const cachedFlattenHit = () => {
+        return cachedProperities;
+      };
+      const hits = [
+        {
+          _source: {
+            [geoFieldName]: '20,100',
+          },
+        },
+      ];
+      const geojson = hitsToGeoJson(hits, cachedFlattenHit, geoFieldName, 'geo_point', []);
+      expect(cachedProperities.hasOwnProperty('location')).toBe(true);
+      expect(geojson.features[0].properties).toEqual({});
+    });
   });
 });
 

x-pack/plugins/maps/common/elasticsearch_util/elasticsearch_geo_utils.ts

@@ -80,7 +80,9 @@ export function hitsToGeoJson(
   const tmpGeometriesAccumulator: Geometry[] = [];
 
   for (let i = 0; i < hits.length; i++) {
-    const properties = flattenHit(hits[i]);
+    // flattenHit returns value from cache. Create new object to avoid modifying flattenHit cache.
+    // not doing deep copy because copying coordinates can be very expensive for complex geometries.
+    const properties = { ...flattenHit(hits[i]) };
 
     tmpGeometriesAccumulator.length = 0; // truncate accumulator