1 files changed, 74 insertions, 0 deletions
diff --git a/js/src/tests/non262/PrivateName/proxy-init-set.js b/js/src/tests/non262/PrivateName/proxy-init-set.js
new file mode 100644
index 0000000000..bc78f50a09
--- /dev/null
+++ b/js/src/tests/non262/PrivateName/proxy-init-set.js
@@ -0,0 +1,74 @@
+// |reftest| 
+// Ensure that the distinction between Proxy Init and Proxy Set holds
+
+function assertThrowsTypeError(f) {
+  var type;
+  try {
+    f();
+  } catch (ex) {
+    type = ex.name;
+  }
+  assertEq(type, 'TypeError');
+}
+
+
+
+var target = {};
+var p1 = new Proxy(target, {});
+var p2 = new Proxy(target, {});
+
+class Base {
+  constructor(o) {
+    return o;
+  }
+}
+
+class A extends Base {
+  #field = 10;
+  static gf(o) {
+    return o.#field;
+  }
+  static sf(o) {
+    o.#field = 15;
+  }
+}
+
+class B extends Base {
+  #field = 25;
+  static gf(o) {
+    return o.#field;
+  }
+  static sf(o) {
+    o.#field = 20;
+  }
+}
+
+// Verify field handling on the proxy we install it on.
+new A(p1);
+assertEq(A.gf(p1), 10);
+A.sf(p1)
+assertEq(A.gf(p1), 15);
+
+// Despite P1 being stamped with A's field, it shouldn't
+// be sufficient to set B's field.
+assertThrowsTypeError(() => B.sf(p1));
+assertThrowsTypeError(() => B.gf(p1));
+assertThrowsTypeError(() => B.sf(p1));
+new B(p1);
+assertEq(B.gf(p1), 25);
+B.sf(p1);
+assertEq(B.gf(p1), 20);
+
+// A's field should't be on the target
+assertThrowsTypeError(() => A.gf(target));
+
+// Can't set the field, doesn't exist
+assertThrowsTypeError(() => A.sf(p2));
+
+// Definitely can't get the field, doesn't exist.
+assertThrowsTypeError(() => A.gf(p2));
+
+// Still should't be on the target.
+assertThrowsTypeError(() => A.gf(target));
+
+if (typeof reportCompare === 'function') reportCompare(0, 0);
+\ No newline at end of file