1 files changed, 68 insertions, 0 deletions
diff --git a/testing/mochitest/tests/Harness_sanity/test_SpecialPowersSpawn.js b/testing/mochitest/tests/Harness_sanity/test_SpecialPowersSpawn.js
new file mode 100644
index 0000000000..06c8dc3c59
--- /dev/null
+++ b/testing/mochitest/tests/Harness_sanity/test_SpecialPowersSpawn.js
@@ -0,0 +1,68 @@
+"use strict";
+
+const { XPCShellContentUtils } = ChromeUtils.import(
+  "resource://testing-common/XPCShellContentUtils.jsm"
+);
+
+XPCShellContentUtils.init(this);
+
+const HTML = String.raw`<!DOCTYPE html>
+<html lang="en">
+<head>
+  <meta charset="UTF-8">
+  <title></title>
+</head>
+<body>
+  <span id="span">Hello there.</span>
+</body>
+</html>`;
+
+const server = XPCShellContentUtils.createHttpServer({
+  hosts: ["example.com"],
+});
+
+server.registerPathHandler("/", (request, response) => {
+  response.setHeader("Content-Type", "text/html");
+  response.write(HTML);
+});
+
+add_task(async function () {
+  // eslint-disable-next-line @microsoft/sdl/no-insecure-url
+  let page = await XPCShellContentUtils.loadContentPage("http://example.com/", {
+    remote: true,
+    remoteSubframes: true,
+  });
+
+  let { SpecialPowers, browsingContext } = page;
+
+  let result = await SpecialPowers.spawn(
+    browsingContext,
+    ["#span"],
+    selector => {
+      let elem = content.document.querySelector(selector);
+      return elem.textContent;
+    }
+  );
+
+  equal(result, "Hello there.", "Got correct element text from frame");
+
+  let line = Components.stack.lineNumber + 1;
+  let callback = () => {
+    let e = new Error("Hello.");
+    return { filename: e.fileName, lineNumber: e.lineNumber };
+  };
+
+  let loc = await SpecialPowers.spawn(browsingContext, [], callback);
+  equal(
+    loc.filename,
+    Components.stack.filename,
+    "Error should have correct script filename"
+  );
+  equal(
+    loc.lineNumber,
+    line + 2,
+    "Error should have correct script line number"
+  );
+
+  await page.close();
+});