LanguageFeatures/Set-literals/type_inference_A09_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 To infer the type of element:
 * ...
 * If element is a spreadElement with expression e1:
 *
 * If P is ? then let S be the inferred type of e1 in context ?:
 * ...
 * If S is dynamic, then the inferred set element type of element is dynamic,
 * the inferred key type of element is dynamic, and the inferred value type of
 * element is dynamic. (We produce both a set element type here, and a key/value
 * pair here and rely on other elements to disambiguate.)
 *
 * @description Checks that if S is dynamic, then the inferred set element type
 * of element is dynamic, the inferred key type of element is dynamic, and the
 * inferred value type of element is dynamic
 * @author sgrekhov@unipro.ru
 */
// SharedOptions=--enable-experiment=constant-update-2018
import "../../Utils/expect.dart";

void listTest1<T>(T t) {
  var s1 = {...t};
  var s2 = {...?t};
  Expect.isFalse(s1 is Set<Object>);
  Expect.isFalse(s2 is Set<Object>);
}

void listTest2<T>(T t) {
  var s1 = {...t};
  var s2 = {...?t};
  Expect.isTrue(s1 is Set<int>);
  Expect.isTrue(s2 is Set<int>);
}

void mapTest1<T>(T t) {
  Map m1 = {...t};
  Map m2 = {...?t};
  Expect.isFalse(m1 is Map<Object, Object>);
  Expect.isFalse(m2 is Map<Object, Object>);
}

void mapTest2<T>(T t) {
  Map m1 = {...t};
  Map m2 = {...?t};
  Expect.isTrue(m1 is Map<int, int>);
  Expect.isTrue(m2 is Map<int, int>);
}

main() {
  listTest1([]);
  listTest2([1, 2, 3]);
  mapTest1({});
  mapTest2({1: 1, 2: 2, 3: 3 });
}