Promise from resize

src/plots/plots.js

@@ -233,9 +233,11 @@ plots.redrawText = function(gd) {
 
 // resize plot about the container size
 plots.resize = function(gd) {
-    if (!gd || d3.select(gd).style('display') === 'none') return;
+    return new Promise(function(resolve, reject) {
 
-    return new Promise(function(resolve) {
+        if (!gd || d3.select(gd).style('display') === 'none'){
+            reject(new Error('Resize must be passed a plot div element.'));
+        }
 
         if (gd._redrawTimer) clearTimeout(gd._redrawTimer);
 
@@ -249,7 +251,7 @@ plots.resize = function(gd) {
 
                 Plotly.relayout(gd, { autosize: true });
                 gd.changed = oldchanged;
-                resolve();
+                resolve(gd);
             }
         }, 100);
     });

test/jasmine/tests/plot_promise_test.js

@@ -464,4 +464,31 @@ describe('Plotly.___ methods', function() {
         });
     });
 
+    describe('Plotly.Plots.resize promise', function() {
+        var initialDiv;
+
+        beforeEach(function(done) {
+            var data = [{ x: [1,2,3], y: [4,5,6] }];
+
+            initialDiv = createGraphDiv();
+
+            Plotly.plot(initialDiv, data, {}).then(done);
+        });
+
+        it('should return a resolved promise of the gd', function(done) {
+            Plotly.Plots.resize(initialDiv).then(function(gd) {
+                expect(gd).toBeDefined();
+                expect(typeof gd).toBe('object');
+                expect(gd.layout).toBeDefined();
+            }).then(done);
+        });
+
+        it('should return a rejected promise with no argument', function(done) {
+            Plotly.Plots.resize().then(null, function(err) {
+                expect(err).toBeDefined();
+                expect(err.message).toBe('Resize must be passed a plot div element.');
+            }).then(done);
+        });
+    });
+
 });