From c9370b937d369c125d64243b095c1a9bc2b5e75c Mon Sep 17 00:00:00 2001
From: ryanhamley <ryan.hamley@mapbox.com>
Date: Thu, 2 Jan 2020 15:03:41 -0800
Subject: [PATCH 1/2] Prevent changing bearing via URL hash when rotation is
 disabled

---
 src/ui/hash.js            |  3 ++-
 test/unit/ui/hash.test.js | 32 ++++++++++++++++++++++++++++++++
 2 files changed, 34 insertions(+), 1 deletion(-)

diff --git a/src/ui/hash.js b/src/ui/hash.js
index fccfea62d83..4a6e17a7ac7 100644
--- a/src/ui/hash.js
+++ b/src/ui/hash.js
@@ -119,10 +119,11 @@ class Hash {
     _onHashChange() {
         const loc = this._getCurrentHash();
         if (loc.length >= 3 && !loc.some(v => isNaN(v))) {
+            const bearing = this._map.dragRotate.isEnabled() && this._map.touchZoomRotate.isEnabled() ? +loc[3] : this._map.getBearing() || 0;
             this._map.jumpTo({
                 center: [+loc[2], +loc[1]],
                 zoom: +loc[0],
-                bearing: +(loc[3] || 0),
+                bearing,
                 pitch: +(loc[4] || 0)
             });
             return true;
diff --git a/test/unit/ui/hash.test.js b/test/unit/ui/hash.test.js
index e81c1d14d33..e1be22ab4ef 100644
--- a/test/unit/ui/hash.test.js
+++ b/test/unit/ui/hash.test.js
@@ -57,6 +57,11 @@ test('hash', (t) => {
         t.equal(map.getBearing(), 0);
         t.equal(map.getPitch(), 0);
 
+        // map is created with `interactive: false`
+        // so explicitly enable rotation for this test
+        map.dragRotate.enable();
+        map.touchZoomRotate.enable();
+
         window.location.hash = '#5/1.00/0.50/30/60';
 
         hash._onHashChange();
@@ -67,6 +72,33 @@ test('hash', (t) => {
         t.equal(map.getBearing(), 30);
         t.equal(map.getPitch(), 60);
 
+        // disable rotation to test that updating
+        // the hash's bearing won't change the map
+        map.dragRotate.disable();
+        map.touchZoomRotate.disable();
+
+        window.location.hash = '#5/1.00/0.50/-45/60';
+
+        hash._onHashChange();
+
+        t.equal(map.getCenter().lng, 0.5);
+        t.equal(map.getCenter().lat, 1);
+        t.equal(map.getZoom(), 5);
+        t.equal(map.getBearing(), 30);
+        t.equal(map.getPitch(), 60);
+
+        // test that a hash with no bearing resets
+        // to the previous bearing when rotation is disabled
+        window.location.hash = '#5/1.00/0.50/';
+
+        hash._onHashChange();
+
+        t.equal(map.getCenter().lng, 0.5);
+        t.equal(map.getCenter().lat, 1);
+        t.equal(map.getZoom(), 5);
+        t.equal(map.getBearing(), 30);
+        t.equal(window.location.hash, '#5/1/0.5/30');
+
         window.location.hash = '#4/wrongly/formed/hash';
 
         t.false(hash._onHashChange());

From 15189fbfa4aa9d6a2605edcdd36c6fc1089acbd9 Mon Sep 17 00:00:00 2001
From: ryanhamley <ryan.hamley@mapbox.com>
Date: Fri, 3 Jan 2020 11:29:05 -0800
Subject: [PATCH 2/2] Remove superfluous null guard

---
 src/ui/hash.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/ui/hash.js b/src/ui/hash.js
index 4a6e17a7ac7..81935c01e64 100644
--- a/src/ui/hash.js
+++ b/src/ui/hash.js
@@ -119,7 +119,7 @@ class Hash {
     _onHashChange() {
         const loc = this._getCurrentHash();
         if (loc.length >= 3 && !loc.some(v => isNaN(v))) {
-            const bearing = this._map.dragRotate.isEnabled() && this._map.touchZoomRotate.isEnabled() ? +loc[3] : this._map.getBearing() || 0;
+            const bearing = this._map.dragRotate.isEnabled() && this._map.touchZoomRotate.isEnabled() ? +loc[3] : this._map.getBearing();
             this._map.jumpTo({
                 center: [+loc[2], +loc[1]],
                 zoom: +loc[0],