From ef5e3890f6e8a54c8fb5ffa2e1c96f6a8f0234b6 Mon Sep 17 00:00:00 2001
From: John Firebaugh <john.firebaugh@gmail.com>
Date: Wed, 27 Sep 2017 13:01:14 -0700
Subject: [PATCH] Ensure the map is updated after the sprite loads

---
 src/style/load_sprite.js      |  7 +----
 src/style/style.js            | 21 ++++++++------
 test/unit/style/style.test.js | 52 ++++++++++++++++++++++++++++++++++-
 3 files changed, 65 insertions(+), 15 deletions(-)

diff --git a/src/style/load_sprite.js b/src/style/load_sprite.js
index 3976e70396f..473d836aee6 100644
--- a/src/style/load_sprite.js
+++ b/src/style/load_sprite.js
@@ -8,14 +8,9 @@ const {RGBAImage} = require('../util/image');
 import type {StyleImage} from './style_image';
 import type {RequestTransformFunction} from '../ui/map';
 
-module.exports = function(baseURL: ?string,
+module.exports = function(baseURL: string,
                           transformRequestCallback: RequestTransformFunction,
                           callback: Callback<{[string]: StyleImage}>) {
-    if (!baseURL) {
-        callback(null, {});
-        return;
-    }
-
     let json: any, image, error;
     const format = browser.devicePixelRatio > 1 ? '@2x' : '';
 
diff --git a/src/style/style.js b/src/style/style.js
index e52fe3cc2b6..197e4e04f23 100644
--- a/src/style/style.js
+++ b/src/style/style.js
@@ -192,17 +192,22 @@ class Style extends Evented {
             this.addSource(id, json.sources[id], {validate: false});
         }
 
-        loadSprite(json.sprite, this.map._transformRequest, (err, images) => {
-            if (err) {
-                this.fire('error', err);
-            } else if (images) {
-                for (const id in images) {
-                    this.imageManager.addImage(id, images[id]);
+        if (json.sprite) {
+            loadSprite(json.sprite, this.map._transformRequest, (err, images) => {
+                if (err) {
+                    this.fire('error', err);
+                } else if (images) {
+                    for (const id in images) {
+                        this.imageManager.addImage(id, images[id]);
+                    }
                 }
-            }
 
+                this.imageManager.setLoaded(true);
+                this.fire('data', {dataType: 'style'});
+            });
+        } else {
             this.imageManager.setLoaded(true);
-        });
+        }
 
         this.glyphManager.setURL(json.glyphs);
 
diff --git a/test/unit/style/style.test.js b/test/unit/style/style.test.js
index 9f4a4cd4dfd..b67c91e00e4 100644
--- a/test/unit/style/style.test.js
+++ b/test/unit/style/style.test.js
@@ -10,6 +10,8 @@ const util = require('../../../src/util/util');
 const Evented = require('../../../src/util/evented');
 const window = require('../../../src/util/window');
 const rtlTextPlugin = require('../../../src/source/rtl_text_plugin');
+const ajax = require('../../../src/util/ajax');
+const browser = require('../../../src/util/browser');
 
 function createStyleJSON(properties) {
     return util.extend({
@@ -170,7 +172,7 @@ test('Style#loadJSON', (t) => {
         callback();
     });
 
-    t.test('fires "dataloading"', (t) => {
+    t.test('fires "dataloading" (synchronously)', (t) => {
         const style = new Style(new StubMap());
         const spy = t.spy();
 
@@ -183,6 +185,54 @@ test('Style#loadJSON', (t) => {
         t.end();
     });
 
+    t.test('fires "data" (asynchronously)', (t) => {
+        const style = new Style(new StubMap());
+
+        style.loadJSON(createStyleJSON());
+
+        style.on('data', (e) => {
+            t.equal(e.target, style);
+            t.equal(e.dataType, 'style');
+            t.end();
+        });
+    });
+
+    t.test('fires "data" when the sprite finishes loading', (t) => {
+        window.useFakeXMLHttpRequest();
+        window.server.respondWith('http://example.com/sprite.json', '{}');
+
+        // Stubbing rather than using a fake response because we need to bypass several Web APIs that
+        // aren't supported by jsdom:
+        //
+        // * `URL.createObjectURL` in ajax.getImage (https://github.com/tmpvar/jsdom/issues/1721)
+        // * `canvas.getContext('2d')` in browser.getImageData
+        //
+        t.stub(ajax, 'getImage').yields(null, new window.Image());
+        t.stub(browser, 'getImageData');
+
+        const style = new Style(new StubMap());
+
+        style.loadJSON({
+            "version": 8,
+            "sources": {},
+            "layers": [],
+            "sprite": "http://example.com/sprite"
+        });
+
+        style.once('data', (e) => {
+            t.equal(e.target, style);
+            t.equal(e.dataType, 'style');
+
+            style.once('data', (e) => {
+                t.equal(e.target, style);
+                t.equal(e.dataType, 'style');
+                t.end();
+            });
+
+            window.server.respond();
+        });
+    });
+
     t.test('validates the style', (t) => {
         const style = new Style(new StubMap());