diff -r 000000000000 -r 6474c204b198 js/src/jit-test/tests/debug/Environment-nondebuggee.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/js/src/jit-test/tests/debug/Environment-nondebuggee.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,40 @@
+// Using an environment that is not a debuggee should throw.
+
+load(libdir + 'asserts.js');
+
+var g = newGlobal();
+var dbg = new Debugger;
+let gw = dbg.addDebuggee(g);
+var log;
+
+function check(env) {
+  assertEq(env.inspectable, false);
+  assertThrowsInstanceOf(() => env.type, Error);
+  assertThrowsInstanceOf(() => env.object, Error);
+  assertThrowsInstanceOf(() => env.parent, Error);
+  assertThrowsInstanceOf(() => env.callee, Error);
+
+  assertThrowsInstanceOf(() => env.names(), Error);
+  assertThrowsInstanceOf(() => env.find('x'), Error);
+  assertThrowsInstanceOf(() => env.getVariable('x'), Error);
+  assertThrowsInstanceOf(() => env.setVariable('x'), Error);
+}
+
+dbg.onDebuggerStatement = function (frame) {
+  log += 'd';
+
+  let env = frame.environment;
+  dbg.removeDebuggee(g);
+  check(env);
+}
+
+log = '';
+g.eval('let x = 42; debugger;');
+assertEq(log, 'd');
+
+dbg.addDebuggee(g);
+g.eval('function f() { }');
+let env = gw.getOwnPropertyDescriptor('f').value.environment;
+assertEq(env.type, 'object');
+dbg.removeDebuggee(g);
+check(env);