Constrain type annotations with deferred types.

tests/language/deferred_constraints_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 "dart:async";
+
+@lazy import "deferred_constraints_lib.dart" as lib;
+import "deferred_constraints_lib.dart" as lib2; /// type_annotation_non_deferred: ok
+
+const lazy = const DeferredLibrary('lib');
+
+class F {}
+class G2<T> {}
+
+void main() {
+  lib.C a = new lib.C(); /// type_annotation1: runtime error, static type warning

[floitsch, 2014/02/28 12:58:15]

these long names make it harder to review, because they don't fit into one line
anymore.

[sigurdm, 2014/03/03 13:18:49]

On the other hand the status files and test run messages are easier to review.
I can change them if you prefer.

+  lib.C a = null; /// type_annotation_null: static type warning
+
+  // In this case we do not defer C.
+  lib2.C a = new lib.C(); /// type_annotation_non_deferred: continued

[floitsch, 2014/02/28 12:58:15]

new lib2.C()?

[sigurdm, 2014/03/03 13:18:49]

Done.

+  lazy.load().then((_) {
+    lib.C a = new lib.C(); /// type_annotation2: dynamic type error, static type warning

[floitsch, 2014/02/28 12:58:15]

don't declare "a", "g" several times.

[sigurdm, 2014/03/03 13:18:49]

Done.

+    lib.G<F> a = new lib.G<F>(); /// type_annotation_generic1: dynamic type error, static type warning
+    G2<lib.C> a = new G2(); /// type_annotation_generic2: static type warning
+    G2<lib.C> a = new G2<lib.C>(); /// type_annotation_generic3: static type warning
+    lib.G<lib.C> a = new lib.G<lib.C>(); /// type_annotation_generic4: dynamic type error, static type warning
+    var a = new lib.C(); /// new: ok
+    var g = new lib.G<F>(); /// new_generic1: ok
+    var g = new G2<lib.C>(); /// new_generic2: static type warning

[floitsch, 2014/02/28 12:58:15]

why is this not a dynamic error?

[sigurdm, 2014/03/03 13:18:49]

That also confused me.
The type arguments of the constructor can be malformed, and the program will
still run without error in checked mode.
Like:

void main() {
  var a = new List<f>();
}

+    var g = new lib.G<lib.C>(); /// new_generic3: static type warning
+    var instance = lib.constantInstance;
+    bool a = instance is lib.Const; /// is_check: runtime error, static type warning
+    instance as lib.Const; /// as_operation: runtime error, static type warning
+    try { throw inst; } on lib.C {} /// catch_check: runtime error, static type warning
+  });
+}
+
+lib.C a = null; /// type_annotation_top_level: static type warning