1 files changed, 31 insertions, 0 deletions
diff --git a/js/src/jit-test/tests/debug/Environment-setVariable-14.js b/js/src/jit-test/tests/debug/Environment-setVariable-14.js
new file mode 100644
index 0000000000..a346a37c6a
--- /dev/null
+++ b/js/src/jit-test/tests/debug/Environment-setVariable-14.js
@@ -0,0 +1,31 @@
+// Debugger.Environment should throw trying to setVariable on a const binding.
+
+load(libdir + "asserts.js");
+
+var g = newGlobal({newCompartment: true});
+var dbg = new Debugger;
+dbg.addDebuggee(g);
+
+g.eval("" + function unaliased() {
+  const x = 42;
+  assertEq(x, 42);
+});
+
+g.eval("" + function aliased() {
+  const x = 42;
+  assertEq(x, 42);
+  return () => x;
+});
+
+dbg.onEnterFrame = (frame) => {
+  frame.onStep = () => {
+    if (frame.environment.getVariable("x") === 42) {
+      assertThrowsInstanceOf(() => frame.environment.setVariable("x", 43), TypeError);
+      assertEq(frame.environment.getVariable("x"), 42);
+    }
+  };
+};
+
+g.unaliased();
+
+g.aliased();