Get the most basic mixin applications working.

tests/language/mixin_test.dart

Index: tests/language/mixin_test.dart
diff --git a/tests/language/mixin_test.dart b/tests/language/mixin_test.dart
new file mode 100644
index 0000000000000000000000000000000000000000..bd819a811f1e76ceb811ee5008e13f8716130791
--- /dev/null
+++ b/tests/language/mixin_test.dart
@@ -0,0 +1,56 @@
+// Copyright (c) 2013, 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.
+
+class S {
+  foo() => "S-foo";
+  baz() => "S-baz";
+}
+
+class M1 {
+  bar() => "M1-bar";
+}
+
+class M2 {
+  bar() => "M2-bar";
+  baz() => "M2-baz";
+}
+
+typedef C = S with M1;
+typedef D = S with M1, M2;
+typedef E = S with M2, M1;
+
+main() {
+  var c = new C();
+  Expect.equals("S-foo", c.foo());
+  Expect.equals("M1-bar", c.bar());
+  Expect.equals("S-baz", c.baz());
+  Expect.isTrue(c is C);
+  Expect.isFalse(c is D);
+  Expect.isFalse(c is E);
+  Expect.isTrue(c is S);
+  Expect.isFalse(c is M1);
+  Expect.isFalse(c is M2);

[gbracha, 2013/01/17 18:24:20]

So per the current spec,  c is M1 should be true. Likewise, d is M1, d is M2, e
is M1 and e is M2 (but not c is M2 of course). See my e-mail.

[kasperl, 2013/01/18 06:21:10]

Thanks, Gilad. Done.

+
+  var d = new D();
+  Expect.equals("S-foo", d.foo());
+  Expect.equals("M2-bar", d.bar());
+  Expect.equals("M2-baz", d.baz());
+  Expect.isFalse(d is C);
+  Expect.isTrue(d is D);
+  Expect.isFalse(d is E);
+  Expect.isTrue(d is S);
+  Expect.isFalse(d is M1);
+  Expect.isFalse(d is M2);
+
+  var e = new E();
+  Expect.equals("S-foo", e.foo());
+  Expect.equals("M1-bar", e.bar());
+  Expect.equals("M2-baz", e.baz());
+  Expect.isFalse(e is C);
+  Expect.isFalse(e is D);
+  Expect.isTrue(e is E);
+  Expect.isTrue(e is S);
+  Expect.isFalse(e is M1);
+  Expect.isFalse(e is M2);
+}