LanguageFeatures/Set-literals/type_inference_A23_t01.dart

// Copyright (c) 2019, 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.

/// @assertion Finally, we define inference on a setOrMapLiteral collection as
/// follows:
/// ...
/// Else, if collection is unambiguously a map literal where P is Map<Pk, Pv>:
/// ...
/// Otherwise the static key type of collection is K where K is determined by
/// downwards inference.
///
/// @description Checks that if collection is unambiguously a map literal and Pk
/// is not ? then the static type of collection is K where K is determined by
/// downwards inference.
/// @author sgrekhov@unipro.ru

import "../../Utils/expect.dart";

main() {
  Map m = {1: 1, 2: 2, 3: 3};
  Expect.isTrue(m is Map<Object?, Object?>);
  Expect.isFalse(m is Map<int, int>);
  Expect.runtimeIsType<Map<Object?, Object?>>(m);
  Expect.runtimeIsNotType<Map<int, int>>(m);
}