1 files changed, 30 insertions, 0 deletions
diff --git a/js/src/jit-test/tests/debug/bug-1477084.js b/js/src/jit-test/tests/debug/bug-1477084.js
new file mode 100644
index 0000000000..2e45a8cc05
--- /dev/null
+++ b/js/src/jit-test/tests/debug/bug-1477084.js
@@ -0,0 +1,30 @@
+// Don't assert trying to force return before the initial yield of an async function.
+
+var g = newGlobal({newCompartment: true});
+g.parent = this;
+g.parentExc = new Error("pants");
+g.eval(`
+  var dbg = new Debugger;
+  var pw = dbg.addDebuggee(parent);
+  var hits = 0;
+  dbg.onExceptionUnwind = function (frame) {
+    dbg.onExceptionUnwind = undefined;
+    return {return: undefined};
+  };
+  dbg.uncaughtExceptionHook = exc => {
+    hits++;
+    assertEq(exc instanceof TypeError, true);
+    assertEq(/force return.*before the initial yield/.test(exc.message), true);
+    return {throw: pw.makeDebuggeeValue(parentExc)};
+  };
+`);
+
+async function* method({ x: callbackfn = unresolvableReference }) {}
+try {
+  method();
+} catch (exc) {
+  g.dbg.enabled = false;
+  assertEq(exc, g.parentExc);
+}
+
+assertEq(g.hits, 1);