Use URLSearchParams instead of transitive dependency querystring

package.json

@@ -153,7 +153,7 @@
   "jest": {
     "testEnvironment": "jest-environment-jsdom-sixteen",
     "testMatch": [
-      "<rootDir>/test/**/*-test.js"
+      "<rootDir>/test/**/*-test.[tj]s"
     ],
     "setupFilesAfterEnv": [
       "<rootDir>/node_modules/matrix-react-sdk/test/setupTests.js"

src/vector/jitsi/index.ts

@@ -17,7 +17,6 @@ limitations under the License.
 // We have to trick webpack into loading our CSS for us.
 require("./index.scss");
 
-import * as qs from 'querystring';
 import { KJUR } from 'jsrsasign';
 import {
     IOpenIDCredentials,
@@ -52,15 +51,16 @@ let meetApi: any; // JitsiMeetExternalAPI
 
 (async function() {
     try {
-        // The widget's options are encoded into the fragment to avoid leaking info to the server. The widget
-        // spec on the other hand requires the widgetId and parentUrl to show up in the regular query string.
-        const widgetQuery = qs.parse(window.location.hash.substring(1));
-        const query = Object.assign({}, qs.parse(window.location.search.substring(1)), widgetQuery);
+        // The widget's options are encoded into the fragment to avoid leaking info to the server.
+        const widgetQuery = new URLSearchParams(window.location.hash.substring(1));
+        // The widget spec on the other hand requires the widgetId and parentUrl to show up in the regular query string.
+        const realQuery = new URLSearchParams(window.location.search.substring(1));
         const qsParam = (name: string, optional = false): string => {
-            if (!optional && (!query[name] || typeof (query[name]) !== 'string')) {
+            const vals = widgetQuery.has(name) ? widgetQuery.getAll(name) : realQuery.getAll(name);
+            if (!optional && vals.length !== 1) {
                 throw new Error(`Expected singular ${name} in query string`);
             }
-            return <string>query[name];
+            return <string>vals[0];
         };
 
         // If we have these params, expect a widget API to be available (ie. to be in an iframe

src/vector/url_utils.ts

@@ -14,7 +14,7 @@ See the License for the specific language governing permissions and
 limitations under the License.
 */
 
-import * as qs from 'querystring';
+import { QueryDict, decodeParams } from "matrix-js-sdk/src/utils";
 
 // We want to support some name / value pairs in the fragment
 // so we're re-using query string like format
@@ -32,15 +32,15 @@ export function parseQsFromFragment(location: Location) {
 
     const result = {
         location: decodeURIComponent(hashparts[0]),
-        params: <qs.ParsedUrlQuery>{},
+        params: <QueryDict>{},
     };
 
     if (hashparts.length > 1) {
-        result.params = qs.parse(hashparts[1]);
+        result.params = decodeParams(hashparts[1]);
     }
     return result;
 }
 
-export function parseQs(location: Location) {
-    return qs.parse(location.search.substring(1));
+export function parseQs(location: Location): QueryDict {
+    return decodeParams(location.search.substring(1));
 }

test/unit-tests/url_utils-test.ts

@@ -0,0 +1,50 @@
+/*
+Copyright 2020 New Vector Ltd
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+import { parseQsFromFragment, parseQs } from "../../src/vector/url_utils";
+
+describe("url_utils.ts", function() {
+    // @ts-ignore
+    const location: Location = {
+        hash: "",
+        search: "",
+    };
+
+    it("parseQsFromFragment", function() {
+        location.hash = "/home?foo=bar";
+        expect(parseQsFromFragment(location)).toEqual({
+            location: "home",
+            params: {
+                "foo": "bar",
+            },
+        });
+    });
+
+    describe("parseQs", function() {
+        location.search = "?foo=bar";
+        expect(parseQs(location)).toEqual({
+            "foo": "bar",
+        });
+    });
+
+    describe("parseQs with arrays", function() {
+        location.search = "?via=s1&via=s2&via=s2&foo=bar";
+        expect(parseQs(location)).toEqual({
+            "via": ["s1", "s2", "s2"],
+            "foo": "bar",
+        });
+    });
+});