Accounting for IDs of cluster features when the promoteID properties is set

CHANGELOG.md

@@ -1,6 +1,7 @@
 ## main
 
 ### ✨ Features and improvements
+- When clustering circles and the promoteId is set to some parameter, the promoted id is used on non-clustered features and the cluster_id is used on clustered features. Previously the id was undefined for non-clustered features.
 - _...Add new stuff here..._
 
 ### 🐞 Bug fixes

src/data/feature_index.test.ts

@@ -0,0 +1,71 @@
+import {FeatureIndex} from './feature_index';
+import {OverscaledTileID} from '../source/tile_id';
+import {VectorTileFeature} from '@mapbox/vector-tile';
+describe('FeatureIndex', () => {
+    describe('getId', () => {
+        const tileID = new OverscaledTileID(0, 0, 0, 0, 0);
+
+        test('converts boolean ids to numbers', () => {
+            const featureIndex = new FeatureIndex(tileID, 'someProperty');
+            const feature = {
+                id: true,
+                properties: {
+                    someProperty: true
+                },
+                geometry: {
+                    type: 'Point',
+                    coordinates: [0, 0]
+                },
+                extent: 4096,
+                type: 1,
+                loadGeometry: () => [],
+                toGeoJSON: () => ({})
+            } as unknown as VectorTileFeature;
+            expect(featureIndex.getId(feature, 'sourceLayer')).toBe(1);
+        });
+
+        test('uses cluster_id when cluster is true and id is undefined', () => {
+            const featureIndex = new FeatureIndex(tileID, 'someProperty');
+            const feature = {
+                id: 1,
+                properties: {
+                    cluster: true,
+                    cluster_id: '123',
+                    someProperty: undefined
+                },
+                geometry: {
+                    type: 'Point',
+                    coordinates: [0, 0]
+                },
+                extent: 4096,
+                type: 1,
+                loadGeometry: () => [],
+                toGeoJSON: () => ({})
+            } as unknown as VectorTileFeature;
+
+            expect(featureIndex.getId(feature, 'sourceLayer')).toBe(123); // cluster_id converted to number
+        });
+
+        test('ignores cluster_id when cluster is false', () => {
+            const featureIndex = new FeatureIndex(tileID, 'someProperty');
+            const feature = {
+                id: 1,
+                properties: {
+                    cluster: false,
+                    cluster_id: '123',
+                    someProperty: undefined
+                },
+                geometry: {
+                    type: 'Point',
+                    coordinates: [0, 0]
+                },
+                extent: 4096,
+                type: 1,
+                loadGeometry: () => [],
+                toGeoJSON: () => ({})
+            } as unknown as VectorTileFeature;
+
+            expect(featureIndex.getId(feature, 'sourceLayer')).toBeUndefined();
+        });
+    });
+});

src/data/feature_index.ts

@@ -300,6 +300,11 @@ export class FeatureIndex {
             const propName = typeof this.promoteId === 'string' ? this.promoteId : this.promoteId[sourceLayerId];
             id = feature.properties[propName] as string | number;
             if (typeof id === 'boolean') id = Number(id);
+
+            // When cluster is true, the id is the cluster_id even though promoteId is set
+            if (id === undefined && feature.properties?.cluster && this.promoteId) {
+                id = Number(feature.properties.cluster_id);
+            }
         }
         return id;
     }