1 files changed, 32 insertions, 0 deletions
diff --git a/js/xpconnect/tests/unit/test_SubscriptLoaderJSMEnvironment.js b/js/xpconnect/tests/unit/test_SubscriptLoaderJSMEnvironment.js
new file mode 100644
index 0000000000..1ae9bc3b74
--- /dev/null
+++ b/js/xpconnect/tests/unit/test_SubscriptLoaderJSMEnvironment.js
@@ -0,0 +1,32 @@
+let tgt_load = {};
+let tgt_check = {};
+
+Services.prefs.setBoolPref("security.allow_eval_with_system_principal", true);
+registerCleanupFunction(() => {
+  Services.prefs.clearUserPref("security.allow_eval_with_system_principal");
+});
+const a = ChromeUtils.import("resource://test/environment_loadscript.jsm", tgt_load);
+const b = ChromeUtils.import("resource://test/environment_checkscript.jsm", tgt_check);
+
+const isShared = Cu.getGlobalForObject(a) === Cu.getGlobalForObject(b);
+
+// Check target bindings
+var tgt_subscript_bound = "";
+for (var name of ["vu", "vq", "vl", "gt", "ed", "ei", "fo", "fi", "fd"])
+    if (tgt_load.target.hasOwnProperty(name))
+        tgt_subscript_bound += name + ",";
+
+// Expected subscript loader behavior is as follows:
+//  - Qualified vars and |this| access occur on target object
+//  - Lexical vars occur on ExtensibleLexicalEnvironment of target object
+//  - Bareword assignments and global |this| access occur on caller's global
+Assert.equal(tgt_load.bound, "vu,ei,fo,fi,", "Should have expected module binding set");
+Assert.equal(tgt_subscript_bound, "vq,gt,ed,fd,", "Should have expected subscript binding set");
+
+// Components should not share namespace
+if (isShared) {
+  todo_check_eq(tgt_check.bound, "");
+  Assert.equal(tgt_check.bound, "ei,fo,", "Modules should have no shared non-eval bindings");
+} else {
+  Assert.equal(tgt_check.bound, "", "Modules should have no shared bindings");
+}