From 2d9001ecc00c08e3aa2d8816f1330e9a340ca34f Mon Sep 17 00:00:00 2001
From: Vladimir Agafonkin <agafonkin@gmail.com>
Date: Wed, 17 Apr 2019 21:59:03 +0300
Subject: [PATCH] Bugfix - removeFeatureState fails with target.id === 0
 (#8150) (#8164)

* Fix an edge case where 0 target.id would fail to clear the feature state

* Check for number & string explicitly

* Add tests for 0 feature ID

* Fix logical check
---
 src/style/style.js       |  4 ++--
 test/unit/ui/map.test.js | 21 +++++++++++++++++++++
 2 files changed, 23 insertions(+), 2 deletions(-)

diff --git a/src/style/style.js b/src/style/style.js
index deff109dd11..45417adefce 100644
--- a/src/style/style.js
+++ b/src/style/style.js
@@ -878,12 +878,12 @@ class Style extends Evented {
             return;
         }
 
-        if (target.id && isNaN(featureId) || featureId < 0) {
+        if (target.id !== undefined && isNaN(featureId) || featureId < 0) {
             this.fire(new ErrorEvent(new Error(`The feature id parameter must be non-negative.`)));
             return;
         }
 
-        if (key && !target.id) {
+        if (key && (typeof target.id !== 'string' && typeof target.id !== 'number')) {
             this.fire(new ErrorEvent(new Error(`A feature id is requred to remove its specific state property.`)));
             return;
         }
diff --git a/test/unit/ui/map.test.js b/test/unit/ui/map.test.js
index 2c95c36c98b..8cd3605fb49 100755
--- a/test/unit/ui/map.test.js
+++ b/test/unit/ui/map.test.js
@@ -1524,6 +1524,27 @@ test('Map', (t) => {
                 t.end();
             });
         });
+        t.test('remove properties for zero-based feature IDs.', (t) => {
+            const map = createMap(t, {
+                style: {
+                    "version": 8,
+                    "sources": {
+                        "geojson": createStyleSource()
+                    },
+                    "layers": []
+                }
+            });
+            map.on('load', () => {
+                map.setFeatureState({ source: 'geojson', id: 0}, {'hover': true, 'foo': true});
+                map.removeFeatureState({ source: 'geojson', id: 0});
+
+                const fState = map.getFeatureState({ source: 'geojson', id: 0});
+                t.equal(fState.hover, undefined);
+                t.equal(fState.foo, undefined);
+
+                t.end();
+            });
+        });
         t.test('other properties persist when removing specific property', (t) => {
             const map = createMap(t, {
                 style: {