1 files changed, 74 insertions, 0 deletions
diff --git a/netwerk/test/unit/test_brotli_unknown_content_type.js b/netwerk/test/unit/test_brotli_unknown_content_type.js
new file mode 100644
index 0000000000..7df0d4f847
--- /dev/null
+++ b/netwerk/test/unit/test_brotli_unknown_content_type.js
@@ -0,0 +1,74 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+// This test file makes sure that we can decode brotli files when the
+// Content-Type header is missing (Bug 1715401)
+
+"use strict";
+
+function emptyBrotli(metadata, response) {
+  response.setHeader("Content-Encoding", "br", false);
+  response.write("\x01\x03\x06\x03");
+}
+
+function largeEmptyBrotli(metadata, response) {
+  response.setHeader("Content-Encoding", "br", false);
+  response.write("\x01\x03" + "\x06".repeat(600) + "\x03");
+}
+
+const { HttpServer } = ChromeUtils.importESModule(
+  "resource://testing-common/httpd.sys.mjs"
+);
+
+ChromeUtils.defineLazyGetter(this, "URL_EMPTY_BROTLI", function () {
+  return (
+    "http://localhost:" + httpServer.identity.primaryPort + "/empty-brotli"
+  );
+});
+
+ChromeUtils.defineLazyGetter(this, "URL_LARGE_EMPTY_BROTLI", function () {
+  return (
+    "http://localhost:" +
+    httpServer.identity.primaryPort +
+    "/large-empty-brotli"
+  );
+});
+
+var httpServer = null;
+
+add_task(async function check_brotli() {
+  httpServer = new HttpServer();
+  httpServer.registerPathHandler("/empty-brotli", emptyBrotli);
+  httpServer.registerPathHandler("/large-empty-brotli", largeEmptyBrotli);
+  httpServer.start(-1);
+
+  async function test(url) {
+    let chan = NetUtil.newChannel({ uri: url, loadUsingSystemPrincipal: true });
+    let [, response] = await new Promise(resolve => {
+      chan.asyncOpen(
+        new ChannelListener(
+          (req, buff) => {
+            resolve([req, buff]);
+          },
+          null,
+          CL_IGNORE_CL
+        )
+      );
+    });
+    return response;
+  }
+  equal(
+    await test(URL_EMPTY_BROTLI),
+    "",
+    "Should decode brotli even when brotli output is empty"
+  );
+  equal(
+    await test(URL_LARGE_EMPTY_BROTLI),
+    "",
+    "Should decode brotli even when the nsUnknownDecoder can't get any decoded output"
+  );
+  Services.prefs.clearUserPref("network.http.accept-encoding");
+  Services.prefs.clearUserPref("network.http.encoding.trustworthy_is_https");
+  await httpServer.stop();
+});