1 files changed, 58 insertions, 0 deletions
diff --git a/js/xpconnect/tests/unit/test_envChain_subscript_in_JSM.js b/js/xpconnect/tests/unit/test_envChain_subscript_in_JSM.js
new file mode 100644
index 0000000000..a95806177e
--- /dev/null
+++ b/js/xpconnect/tests/unit/test_envChain_subscript_in_JSM.js
@@ -0,0 +1,58 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+"use strict";
+
+// Verify the environment chain for subscripts in JSM described in
+// js/src/vm/EnvironmentObject.h.
+
+add_task(async function() {
+  const { envs } = ChromeUtils.import("resource://test/envChain_subscript.jsm");
+
+  Assert.equal(envs.length, 6);
+
+  let i = 0, env;
+
+  env = envs[i]; i++;
+  Assert.equal(env.type, "NonSyntacticLexicalEnvironmentObject");
+  Assert.equal(env.qualified, false);
+  Assert.equal(env.unqualified, false);
+  Assert.equal(env.lexical, true, "lexical must live in the NSLEO");
+  Assert.equal(env.prop, false);
+
+  env = envs[i]; i++;
+  Assert.equal(env.type, "WithEnvironmentObject");
+  Assert.equal(env.qualified, true, "qualified var must live in the with env");
+  Assert.equal(env.unqualified, false);
+  Assert.equal(env.lexical, false);
+  Assert.equal(env.prop, true, "this property must live in the with env");
+
+  env = envs[i]; i++;
+  Assert.equal(env.type, "NonSyntacticLexicalEnvironmentObject");
+  Assert.equal(env.qualified, false);
+  Assert.equal(env.unqualified, false);
+  Assert.equal(env.lexical, false);
+  Assert.equal(env.prop, false);
+
+  env = envs[i]; i++;
+  Assert.equal(env.type, "NonSyntacticVariablesObject");
+  Assert.equal(env.qualified, false);
+  Assert.equal(env.unqualified, true, "unqualified var must live in the global");
+  Assert.equal(env.lexical, false);
+  Assert.equal(env.prop, false);
+
+  env = envs[i]; i++;
+  Assert.equal(env.type, "GlobalLexicalEnvironmentObject");
+  Assert.equal(env.qualified, false);
+  Assert.equal(env.unqualified, false);
+  Assert.equal(env.lexical, false);
+  Assert.equal(env.prop, false);
+
+  env = envs[i]; i++;
+  Assert.equal(env.type, "*BackstagePass*");
+  Assert.equal(env.qualified, false);
+  Assert.equal(env.unqualified, false);
+  Assert.equal(env.lexical, false);
+  Assert.equal(env.prop, false);
+});