Migrate language block 45 - call_argument ... call_with.

tests/language/call_operator_test.dart

-// Copyright (c) 2012, 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";
-
-// simple test with no types in signature
-class A1 {
-  call() => 42;
-}
-
-// same test, include return type
-class A2 {
-  int call() => 35;
-}
-
-class B {
-  call() => 28;
-}
-
-// A call() operator can have any arity
-class C {
-  call(arg) => 7 * arg;
-}
-
-// Test named arguments
-class D {
-  call([arg = 6]) => 7 * arg;
-}
-
-// Non-trivial method body combination of positional and named.
-class E {
-  String call(String str, {int count: 1}) {
-    StringBuffer buffer = new StringBuffer();
-    for (var i = 0; i < count; i++) {
-      buffer.write(str);
-      if (i < count - 1) {
-        buffer.write(":");
-      }
-    }
-    return buffer.toString();
-  }
-}
-
-main() {
-  var a1 = new A1();
-  Expect.equals(42, a1());
-  Expect.equals(42, a1.call());
-
-  var a2 = new A2();
-  Expect.equals(35, a2());
-  Expect.equals(35, a2.call());
-
-  var b = new B();
-  Expect.equals(28, b());
-  Expect.equals(28, b.call());
-
-  var c = new C();
-  Expect.equals(42, c(6));
-  Expect.equals(42, c.call(6));
-
-  var d = new D();
-  Expect.equals(42, d());
-  Expect.equals(7, d(1));
-  Expect.equals(14, d(2));
-  Expect.equals(42, d.call());
-  Expect.equals(7, d.call(1));
-  Expect.equals(14, d.call(2));
-
-  var e = new E();
-  Expect.equals("foo", e("foo"));
-  Expect.equals("foo:foo", e("foo", count: 2));
-  Expect.equals("foo:foo:foo", e("foo", count: 3));
-  Expect.equals("foo", e.call("foo"));
-  Expect.equals("foo:foo", e.call("foo", count: 2));
-  Expect.equals("foo:foo:foo", e.call("foo", count: 3));
-
-  Expect.isTrue(a1 is Function);
-  Expect.isTrue(e is Function);
-}