From de7af654e35a840f1371be57028d28feac83cfbf Mon Sep 17 00:00:00 2001
From: Patrick Hulce <patrick.hulce@gmail.com>
Date: Wed, 18 Jul 2018 16:57:44 -0700
Subject: [PATCH] core(optimized-images): support non-standard mime types

---
 .../gatherers/dobetterweb/optimized-images.js |  4 +++-
 .../test/audits/dobetterweb/doctype-test.js   |  2 +-
 .../dobetterweb/optimized-images-test.js      | 21 ++++++++++++++++++-
 3 files changed, 24 insertions(+), 3 deletions(-)

diff --git a/lighthouse-core/gather/gatherers/dobetterweb/optimized-images.js b/lighthouse-core/gather/gatherers/dobetterweb/optimized-images.js
index b593ae9c1019..80ee69be4922 100644
--- a/lighthouse-core/gather/gatherers/dobetterweb/optimized-images.js
+++ b/lighthouse-core/gather/gatherers/dobetterweb/optimized-images.js
@@ -21,6 +21,8 @@ const WEBP_QUALITY = 0.85;
 
 const MINIMUM_IMAGE_SIZE = 4096; // savings of <4 KB will be ignored in the audit anyway
 
+const IMAGE_REGEX = /^image\/((x|ms|x-ms)-)?(png|bmp|jpeg)$/;
+
 /** @typedef {{isSameOrigin: boolean, isBase64DataUri: boolean, requestId: string, url: string, mimeType: string, resourceSize: number}} SimplifiedNetworkRecord */
 
 /* global document, Image, atob */
@@ -87,7 +89,7 @@ class OptimizedImages extends Gatherer {
 
       seenUrls.add(record.url);
       const isOptimizableImage = record.resourceType === NetworkRequest.TYPES.Image &&
-        /image\/(png|bmp|jpeg)/.test(record.mimeType);
+        IMAGE_REGEX.test(record.mimeType);
       const isSameOrigin = URL.originsMatch(pageUrl, record.url);
       const isBase64DataUri = /^data:.{2,40}base64\s*,/.test(record.url);
 
diff --git a/lighthouse-core/test/audits/dobetterweb/doctype-test.js b/lighthouse-core/test/audits/dobetterweb/doctype-test.js
index 937aa568a505..b77e49bf1c38 100644
--- a/lighthouse-core/test/audits/dobetterweb/doctype-test.js
+++ b/lighthouse-core/test/audits/dobetterweb/doctype-test.js
@@ -8,7 +8,7 @@
 const Audit = require('../../../audits/dobetterweb/doctype.js');
 const assert = require('assert');
 
-/* eslint-env mocha */
+/* eslint-env jest */
 
 describe('DOBETTERWEB: doctype audit', () => {
   it('fails when document does not contain a doctype', () => {
diff --git a/lighthouse-core/test/gather/gatherers/dobetterweb/optimized-images-test.js b/lighthouse-core/test/gather/gatherers/dobetterweb/optimized-images-test.js
index 68dfe839c555..d017f0387938 100644
--- a/lighthouse-core/test/gather/gatherers/dobetterweb/optimized-images-test.js
+++ b/lighthouse-core/test/gather/gatherers/dobetterweb/optimized-images-test.js
@@ -5,7 +5,7 @@
  */
 'use strict';
 
-/* eslint-env mocha */
+/* eslint-env jest */
 
 const OptimizedImages =
     require('../../../../gather/gatherers/dobetterweb/optimized-images');
@@ -185,4 +185,23 @@ describe('Optimized images', () => {
       assert.ok(/gmail.*image.jpg/.test(artifact[3].url));
     });
   });
+
+  it('handles non-standard mime types too', async () => {
+    const traceData = {
+      networkRecords: [
+        {
+          requestId: '1',
+          url: 'http://google.com/image.bmp?x-ms',
+          mimeType: 'image/x-ms-bmp',
+          resourceSize: 12000,
+          transferSize: 20000,
+          resourceType: 'Image',
+          finished: true,
+        },
+      ],
+    };
+
+    const artifact = await optimizedImages.afterPass(options, traceData);
+    expect(artifact).toHaveLength(1);
+  });
 });