Adds key property to torque layers to keep property publicaly exposed

lib/torque/gmaps/torque.js

@@ -10,6 +10,11 @@ function GMapsTorqueLayer(options) {
     throw new Error("browser is not supported by torque");
   }
   this.keys = [0];
+  Object.defineProperty(this, 'key', {
+    get: function() {
+      return this.getKey();
+    }
+  });
   this.shader = null;
   this.ready = false;
   this.options = torque.extend({}, options);

lib/torque/leaflet/torque.js

@@ -27,6 +27,11 @@ L.TorqueLayer = L.CanvasLayer.extend({
     }
     options.tileLoader = true;
     this.keys = [0];
+    Object.defineProperty(this, 'key', {
+      get: function() {
+        return this.getKey();
+      }
+    });
     this.prevRenderedKey = 0;
     if (options.cartocss) {
       torque.extend(options, torque.common.TorqueLayer.optionsFromCartoCSS(options.cartocss));

test/leaflet/torque-layer.js

@@ -0,0 +1,9 @@
+var torque = require('../../lib/torque/index');
+
+QUnit.module('leaflet-torque-layer');
+
+test('exposes key property', function(assert) {
+  var torqueLayer = new L.TorqueLayer({});
+  assert.equal(torqueLayer.key, 0);
+  assert.equal(torqueLayer.getKey(), torqueLayer.key);
+});

test/suite.js

@@ -1,6 +1,7 @@
 require('qunitjs');
 
 require('./core');
+require('./leaflet/torque-layer');
 require('./torque');
 require('./renderer/point');
 require('./provider.jsonarray');