1 files changed, 38 insertions, 0 deletions
diff --git a/devtools/server/tests/xpcshell/test_getyoungestframe.js b/devtools/server/tests/xpcshell/test_getyoungestframe.js
new file mode 100644
index 0000000000..8af9981e22
--- /dev/null
+++ b/devtools/server/tests/xpcshell/test_getyoungestframe.js
@@ -0,0 +1,38 @@
+/* eslint-disable strict */
+function run_test() {
+  Services.prefs.setBoolPref("security.allow_eval_with_system_principal", true);
+  registerCleanupFunction(() => {
+    Services.prefs.clearUserPref("security.allow_eval_with_system_principal");
+  });
+  const { addDebuggerToGlobal } = ChromeUtils.importESModule(
+    "resource://gre/modules/jsdebugger.sys.mjs"
+  );
+  addDebuggerToGlobal(globalThis);
+  const xpcInspector = Cc["@mozilla.org/jsinspector;1"].getService(
+    Ci.nsIJSInspector
+  );
+  const g = createTestGlobal("test1");
+
+  const dbg = makeDebugger();
+  dbg.uncaughtExceptionHook = testExceptionHook;
+
+  dbg.addDebuggee(g);
+  dbg.onDebuggerStatement = function(frame) {
+    Assert.ok(frame === dbg.getNewestFrame());
+    // Execute from the nested event loop, dbg.getNewestFrame() won't
+    // be working anymore.
+
+    executeSoon(function() {
+      try {
+        Assert.ok(frame === dbg.getNewestFrame());
+      } finally {
+        xpcInspector.exitNestedEventLoop("test");
+      }
+    });
+    xpcInspector.enterNestedEventLoop("test");
+  };
+
+  g.eval("function debuggerStatement() { debugger; }; debuggerStatement();");
+
+  dbg.disable();
+}