Match parens recursively on URLs to not fix embeded calls

Author: sontek

fixUrls.js

@@ -29,8 +29,9 @@ module.exports = function (css) {
   var currentDir = baseUrl + location.pathname.replace(/\/[^\/]*$/, "/");
 
 	// convert each url(...)
-	var fixedCss = css.replace(/url *\( *(.+?) *\)/g, function(fullMatch, origUrl) {
+	var fixedCss = css.replace(/url\(((?:[^)(]+|\((?:[^)(]+|\([^)(]*\))*\))*)\)/g, function(fullMatch, origUrl) {
 		// strip quotes (if they exist)
+
 		var unquotedOrigUrl = origUrl
 			.replace(/^"(.*)"$/, function(o, $1){ return $1; })
 			.replace(/^'(.*)'$/, function(o, $1){ return $1; });

test/fixUrlsTest.js

@@ -180,4 +180,12 @@ describe("fix urls tests", function() {
           "http://x.y.z"
       );
     });
+
+    it("Doesn't break inline SVG", function() {
+        const svg = "url('data:image/svg+xml;charset=utf-8,<svg><feFlood flood-color=\"rgba(0,0,0,0.5)\" /></svg>')";
+
+        assertUrl(
+            "body: {  background: " + svg + " }"
+        );
+    });
 });