Add tests for generic methods in strong mode

tests/language_strong/generic_methods_unused_parameter_test.dart

+// Copyright (c) 2017, 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.
+
+// Test that generic methods with unused parameters aren't treated as
+// non-generic methods, but can be specialized as such.
+
+library generic_methods_unused_parameter_test;
+
+import "package:expect/expect.dart";
+
+typedef Fun = int Function();
+typedef FunReq = int Function(int);
+typedef FunOpt = int Function([int]);
+typedef FunReqOpt = int Function(int, [int]);
+typedef FunNam = int Function({int p});
+typedef FunReqNam = int Function(int, {int p});
+
+typedef FunTyp = int Function<T>();
+typedef FunTypReq = int Function<T>(int);
+typedef FunTypOpt = int Function<T>([int]);
+typedef FunTypReqOpt = int Function<T>(int, [int]);
+typedef FunTypNam = int Function<T>({int p});
+typedef FunTypReqNam = int Function<T>(int, {int p});
+
+int fun() {}
+int funReq(int x) => x;
+int funOpt([int y]) => y ?? 42;
+int funReqOpt(int x, [int y]) => x;
+int funNam({int p}) => p ?? 42;
+int funReqNam(int x, {int p}) => x;
+
+int funTyp<T>() {}
+int funTypReq<T>(int x) => x;
+int funTypOpt<T>([int y]) => y ?? 42;
+int funTypReqOpt<T>(int x, [int y]) => x;
+int funTypNam<T>({int p}) => p ?? 42;
+int funTypReqNam<T>(int x, {int p}) => x;
+
+main() {
+  Fun varFun = funTyp;
+  FunReq varFunReq = funTypReq;
+  FunOpt varFunOpt = funTypOpt;
+  FunReqOpt varFunReqOpt = funTypReqOpt;
+  FunNam varFunNam = funTypNam;
+  FunReqNam varFunReqNam = funTypReqNam;
+
+  Expect.isTrue(fun is Fun);
+  Expect.isTrue(fun is! FunTyp);
+  Expect.isTrue(funTyp is! Fun);
+  Expect.isTrue(funTyp is FunTyp);
+  Expect.isTrue(varFun is Fun);
+  Expect.isTrue(varFun is! FunTyp);
+
+  Expect.isTrue(funReq is FunReq);
+  Expect.isTrue(funReq is! FunTypReq);
+  Expect.isTrue(funTypReq is! FunReq);
+  Expect.isTrue(funTypReq is FunTypReq);
+  Expect.isTrue(varFunReq is FunReq);
+  Expect.isTrue(varFunReq is! FunTypReq);
+
+  Expect.isTrue(funOpt is FunOpt);
+  Expect.isTrue(funOpt is! FunTypOpt);
+  Expect.isTrue(funTypOpt is! FunOpt);
+  Expect.isTrue(funTypOpt is FunTypOpt);
+  Expect.isTrue(varFunOpt is FunOpt);
+  Expect.isTrue(varFunOpt is! FunTypOpt);
+
+  Expect.isTrue(funReqOpt is FunReqOpt);
+  Expect.isTrue(funReqOpt is! FunTypReqOpt);
+  Expect.isTrue(funTypReqOpt is! FunReqOpt);
+  Expect.isTrue(funTypReqOpt is FunTypReqOpt);
+  Expect.isTrue(varFunReqOpt is FunReqOpt);
+  Expect.isTrue(varFunReqOpt is! FunTypReqOpt);
+
+  Expect.isTrue(funNam is FunNam);
+  Expect.isTrue(funNam is! FunTypNam);
+  Expect.isTrue(funTypNam is! FunNam);
+  Expect.isTrue(funTypNam is FunTypNam);
+  Expect.isTrue(varFunNam is FunNam);
+  Expect.isTrue(varFunNam is! FunTypNam);
+
+  Expect.isTrue(funReqNam is FunReqNam);
+  Expect.isTrue(funReqNam is! FunTypReqNam);
+  Expect.isTrue(funTypReqNam is! FunReqNam);
+  Expect.isTrue(funTypReqNam is FunTypReqNam);
+  Expect.isTrue(varFunReqNam is FunReqNam);
+  Expect.isTrue(varFunReqNam is! FunTypReqNam);
+}