From d43cfca00a207f2e104d69134dbd1706254d314b Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=C3=89tienne=20T=C3=A9treault-Pinard?= <etienne@plot.ly>
Date: Thu, 4 Aug 2016 13:44:53 -0400
Subject: [PATCH] mapbox: skip over non-object layer containers

- and keep track of input index with '_index'
---
 src/plots/mapbox/layout_defaults.js |  5 ++++-
 test/jasmine/tests/mapbox_test.js   | 14 ++++++++++++++
 2 files changed, 18 insertions(+), 1 deletion(-)

diff --git a/src/plots/mapbox/layout_defaults.js b/src/plots/mapbox/layout_defaults.js
index 59c91057f31..6772c1786c7 100644
--- a/src/plots/mapbox/layout_defaults.js
+++ b/src/plots/mapbox/layout_defaults.js
@@ -50,9 +50,11 @@ function handleLayerDefaults(containerIn, containerOut) {
     }
 
     for(var i = 0; i < layersIn.length; i++) {
-        layerIn = layersIn[i] || {};
+        layerIn = layersIn[i];
         layerOut = {};
 
+        if(!Lib.isPlainObject(layerIn)) continue;
+
         var sourceType = coerce('sourcetype');
         coerce('source');
 
@@ -86,6 +88,7 @@ function handleLayerDefaults(containerIn, containerOut) {
             coerce('symbol.textposition');
         }
 
+        layerOut._index = i;
         layersOut.push(layerOut);
     }
 }
diff --git a/test/jasmine/tests/mapbox_test.js b/test/jasmine/tests/mapbox_test.js
index 40b97b7fa20..29df105616f 100644
--- a/test/jasmine/tests/mapbox_test.js
+++ b/test/jasmine/tests/mapbox_test.js
@@ -80,6 +80,20 @@ describe('mapbox defaults', function() {
         expect(layoutOut.mapbox.layers[1].sourcetype).toEqual('geojson');
     });
 
+    it('should skip over non-object layer containers', function() {
+        layoutIn = {
+            mapbox: {
+                layers: [{}, null, 'remove', {}]
+            }
+        };
+
+        supplyLayoutDefaults(layoutIn, layoutOut, fullData);
+        expect(layoutOut.mapbox.layers[0].sourcetype).toEqual('geojson');
+        expect(layoutOut.mapbox.layers[0]._index).toEqual(0);
+        expect(layoutOut.mapbox.layers[1].sourcetype).toEqual('geojson');
+        expect(layoutOut.mapbox.layers[1]._index).toEqual(3);
+    });
+
     it('should coerce \'sourcelayer\' only for *vector* \'sourcetype\'', function() {
         layoutIn = {
             mapbox: {