Insert checks before deferred calls and accesses.

tests/language/deferred_not_loaded_check_test.dart

+// Copyright (c) 2014, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+import 'package:expect/expect.dart';
+import 'package:async_helper/async_helper.dart';
+
+import "deferred_not_loaded_check_lib.dart" deferred as lib;
+
+// Test that we give appropriate errors when accessing an element that is not
+// yet loaded.
+
+var c;
+
+expectNoSideEffect(test) {
+  c = 0;
+  test();
+  Expect.isTrue(c == 0);
+}
+
+expectThrowsNotLoaded(test){
+  Expect.throws(test, (e) => e is Error);
+}
+
+int sideEffect() {
+  c = 1;
+  return 10;
+}
+
+void main() {
+  expectNoSideEffect(() {
+    expectThrowsNotLoaded(() {
+      lib.foo(sideEffect());
+    });
+  });
+  expectNoSideEffect(() {
+    expectThrowsNotLoaded(() {
+      lib.C.foo(sideEffect());
+    });
+  });
+  expectNoSideEffect(() {
+    expectThrowsNotLoaded(() {
+      new lib.C(sideEffect());
+    });
+  });
+  expectThrowsNotLoaded(() {
+    lib.a;
+  });
+  expectNoSideEffect(() {
+    expectThrowsNotLoaded(() {
+      lib.a = sideEffect();
+    });
+  });
+  expectThrowsNotLoaded(() {
+    lib.getter;
+  });
+  expectNoSideEffect(() {
+    expectThrowsNotLoaded(() {
+      lib.setter = sideEffect();
+    });
+  });
+  expectNoSideEffect(() {
+    expectThrowsNotLoaded(() {
+      lib.list[sideEffect()] = sideEffect();
+    });
+  });
+  expectNoSideEffect(() {
+    expectThrowsNotLoaded(() {
+      lib.closure(sideEffect());
+    });
+  });
+}