1 files changed, 9 insertions, 0 deletions
diff --git a/js/src/jit-test/tests/basic/bug1707820.js b/js/src/jit-test/tests/basic/bug1707820.js
new file mode 100644
index 0000000000..d635965f7a
--- /dev/null
+++ b/js/src/jit-test/tests/basic/bug1707820.js
@@ -0,0 +1,9 @@
+gczeal(4);
+let a = "x".repeat(100);
+for (let i = 0; i < 50; i++) {
+  let s = new String(a);
+  s.a = 0;
+  s.b = 0;
+  delete s.a;
+  Object.keys(s);
+}