From 8188af202f3c58d0f22f01e9d28c51f0d021e6a8 Mon Sep 17 00:00:00 2001
From: Molly Lloyd <molly@mapbox.com>
Date: Tue, 19 Sep 2017 15:11:45 -0700
Subject: [PATCH] guard for offset edgecase in flyTo

---
 src/ui/camera.js            | 2 +-
 test/unit/ui/camera.test.js | 7 +++++++
 2 files changed, 8 insertions(+), 1 deletion(-)

diff --git a/src/ui/camera.js b/src/ui/camera.js
index 227f09b3847..be14ef805a5 100644
--- a/src/ui/camera.js
+++ b/src/ui/camera.js
@@ -785,7 +785,7 @@ class Camera extends Evented {
         let S = (r(1) - r0) / rho;
 
         // When u₀ = u₁, the optimal path doesn’t require both ascent and descent.
-        if (Math.abs(u1) < 0.000001 || isNaN(S)) {
+        if (Math.abs(u1) < 0.000001 || isNaN(S) || S === Infinity) {
             // Perform a more or less instantaneous transition if the path is too short.
             if (Math.abs(w0 - w1) < 0.000001) return this.easeTo(options, eventData);
 
diff --git a/test/unit/ui/camera.test.js b/test/unit/ui/camera.test.js
index ec655ff378d..2673ebbcf77 100644
--- a/test/unit/ui/camera.test.js
+++ b/test/unit/ui/camera.test.js
@@ -788,7 +788,14 @@ test('camera', (t) => {
             const camera = createCamera({zoom: 22, center:[0, 0]});
             t.doesNotThrow(()=>camera.flyTo({zoom:10, center:[0, 0]}));
             t.end();
+        });
 
+        t.test('does not throw when cameras current zoom is above maxzoom and an offset creates infinite zoom out factor', (t)=>{
+            const transform = new Transform(0, 20.9999, true);
+            transform.resize(512, 512);
+            const camera = new Camera(transform, {}).jumpTo({zoom: 21, center:[0, 0]});
+            t.doesNotThrow(()=>camera.flyTo({zoom:7.5, center:[0, 0], offset:[0, 70]}));
+            t.end();
         });
 
         t.test('zooms to specified level', (t) => {