From 7cd062ec684981f381e8266b61f7788edee75a27 Mon Sep 17 00:00:00 2001
From: Calixte Denizet <calixte.denizet@gmail.com>
Date: Wed, 19 Jul 2023 20:14:18 +0200
Subject: [PATCH] Draw correctly background images in ref tests

It's a workaround for bug https://bugzilla.mozilla.org/show_bug.cgi?id=1844414.
It should be reverted (in order to avoid a perf penalty) once the bug is fixed
in Firefox.
---
 test/driver.js | 21 +++++++++++++++------
 1 file changed, 15 insertions(+), 6 deletions(-)

diff --git a/test/driver.js b/test/driver.js
index 65028017a..1df6232de 100644
--- a/test/driver.js
+++ b/test/driver.js
@@ -61,16 +61,12 @@ function loadStyles(styles) {
   return Promise.all(promises);
 }
 
-function writeSVG(svgElement, ctx) {
-  // We need to have UTF-8 encoded XML.
-  const svg_xml = unescape(
-    encodeURIComponent(new XMLSerializer().serializeToString(svgElement))
-  );
+function loadImage(svg_xml, ctx) {
   return new Promise((resolve, reject) => {
     const img = new Image();
     img.src = "data:image/svg+xml;base64," + btoa(svg_xml);
     img.onload = function () {
-      ctx.drawImage(img, 0, 0);
+      ctx?.drawImage(img, 0, 0);
       resolve();
     };
     img.onerror = function (e) {
@@ -79,6 +75,19 @@ function writeSVG(svgElement, ctx) {
   });
 }
 
+async function writeSVG(svgElement, ctx) {
+  // We need to have UTF-8 encoded XML.
+  const svg_xml = unescape(
+    encodeURIComponent(new XMLSerializer().serializeToString(svgElement))
+  );
+  if (svg_xml.includes("background-image: url(&quot;data:image")) {
+    // Workaround for https://bugzilla.mozilla.org/show_bug.cgi?id=1844414
+    // we load the image two times.
+    await loadImage(svg_xml, null);
+  }
+  return loadImage(svg_xml, ctx);
+}
+
 async function inlineImages(node, silentErrors = false) {
   const promises = [];