import FIREFOX_52_6_0esr_RELEASE from mozilla-esr52 hg repo

devtools/server/tests/browser/browser_stylesheets_nested-iframes.js

@@ -0,0 +1,38 @@
+/* vim: set ft=javascript ts=2 et sw=2 tw=80: */
+/* Any copyright is dedicated to the Public Domain.
+   http://creativecommons.org/publicdomain/zero/1.0/ */
+
+"use strict";
+
+// Test that StyleSheetsActor.getStyleSheets() works if an iframe does not have
+// a content document.
+
+const {StyleSheetsFront} = require("devtools/shared/fronts/stylesheets");
+
+add_task(function* () {
+  let browser = yield addTab(MAIN_DOMAIN + "stylesheets-nested-iframes.html");
+  let doc = browser.contentDocument;
+
+  info("Initialising the debugger server and client.");
+  initDebuggerServer();
+  let client = new DebuggerClient(DebuggerServer.connectPipe());
+  let form = yield connectDebuggerClient(client);
+
+  info("Attaching to the active tab.");
+  yield client.attachTab(form.actor);
+
+  let front = StyleSheetsFront(client, form);
+  ok(front, "The StyleSheetsFront was created.");
+
+  let sheets = yield front.getStyleSheets();
+  ok(sheets, "getStyleSheets() succeeded even with documentless iframes.");
+
+  // Bug 285395 limits the number of nested iframes to 10. There's one sheet per
+  // frame so we should get 10 sheets. However, the limit might change in the
+  // future so it's better not to rely on the limit. Asserting > 2 ensures that
+  // the test page is actually loading nested iframes and this test is doing
+  // something sensible (if we got this far, the test has served its purpose).
+  ok(sheets.length > 2, sheets.length + " sheets found (expected 3 or more).");
+
+  yield client.close();
+});