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1/*
2 * Copyright (c) 2023 Huawei Device Co., Ltd.
3 * Licensed under the Apache License, Version 2.0 (the "License");
4 * you may not use this file except in compliance with the License.
5 * You may obtain a copy of the License at
6 *
7 *     http://www.apache.org/licenses/LICENSE-2.0
8 *
9 * Unless required by applicable law or agreed to in writing, software
10 * distributed under the License is distributed on an "AS IS" BASIS,
11 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 * See the License for the specific language governing permissions and
13 * limitations under the License.
14 */
15/**---
16 description: >
17    typescript 2.3 adds support for declaring defaults for generic type parameters.
18    a class or interface declaration that merges with an existing class or interface declaration may introduce a default for an existing type parameter.
19    a class or interface declaration that merges with an existing class or interface declaration may introduce a new type parameter as long as it specifies a default.
20 module: ESNext
21 isCurrent: true
22 ---*/
23
24
25import { Assert } from '../../../suite/assert.js'
26
27class CA<V, T, U>{
28   ca0: V;
29   ca1: T;
30   ca2: U;
31   constructor(ca0: V, ca1: T, ca2: U) { this.ca0 = ca0; this.ca1 = ca1; this.ca2 = ca2; }
32   creatOBJ() {
33      let a = this.ca0;
34      let b = this.ca1;
35      let c = this.ca2;
36      return { a, b, c };
37   }
38   toJSON() {
39      return JSON.stringify(this.creatOBJ());
40   }
41}
42class CCA<V = number, T = V[], U = T[]> extends CA<V, T, U>{ }
43let cca1 = new CCA(0, [0, 0], "[0]");
44Assert.equal(cca1.toJSON(), "{\"a\":0,\"b\":[0,0],\"c\":\"[0]\"}");
45let cca2 = new CCA<string>("A", ["A"], [["A"], ["B"]]);
46Assert.equal(cca2.toJSON(), "{\"a\":\"A\",\"b\":[\"A\"],\"c\":[[\"A\"],[\"B\"]]}");
47
48interface IB<V, T, U> {
49   ia: V;
50   ib: T;
51   ic: U;
52}
53interface CIB<V = number, T = V[], U = T[]> extends IB<V, T, U> { }
54let cib1: CIB = { ia: 0, ib: [0], ic: [[0], [1, 2]] };
55Assert.equal(JSON.stringify(cib1), "{\"ia\":0,\"ib\":[0],\"ic\":[[0],[1,2]]}");
56let cib2: CIB<string> = { ia: "A", ib: ["A", "B"], ic: [["A"], ["B", "C"]] };
57Assert.equal(JSON.stringify(cib2), "{\"ia\":\"A\",\"ib\":[\"A\",\"B\"],\"ic\":[[\"A\"],[\"B\",\"C\"]]}");
58