// Copyright (c) 2020, 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.

// Tests `is` checks and `as` casts between various JS objects. Currently, all
// checks and casts should be allowed between JS objects.

@JS()
library is_check_and_as_cast_test;

import 'package:js/js.dart';
import 'package:expect/minitest.dart';

@JS()
external void eval(String code);

@JS()
class Foo {
  external Foo(int a);
  external int get a;
}

// Class with same structure as Foo but separate JS class.
@JS()
class Bar {
  external Bar(int a);
  external int get a;
}

@JS('Bar')
class BarCopy {
  external BarCopy(int a);
  external int get a;
}

@JS()
class Baz {
  external Baz(int a, int b);
  external int get a;
  external int get b;
}

// JS object literals
@JS()
@anonymous
class LiteralA {
  external int get x;
}

@JS()
@anonymous
class LiteralB {
  external int get y;
}

// Library is annotated with JS so we don't need the annotation here.
external LiteralA get a;
external LiteralB get b;

void main() {
  eval(r"""
    function Foo(a) {
      this.a = a;
    }
    function Bar(a) {
      this.a = a;
    }
    function Baz(a, b) {
      Foo.call(this, a);
      this.b = b;
    }
    Baz.prototype.__proto__ = Foo.prototype;
    var a = {
      x: 1,
    };
    var b = {
      y: 2,
    };
      """);

  // JS class object can be checked and casted with itself.
  var foo = Foo(42);
  expect(foo is Foo, isTrue);
  expect(() => (foo as Foo), returnsNormally);

  // Try it with dynamic.
  dynamic d = Foo(42);
  expect(d is Foo, isTrue);
  expect(() => (d as Foo), returnsNormally);

  // Casts are allowed between any JS class objects.
  expect(foo is Bar, isTrue);
  expect(d is Bar, isTrue);
  expect(() => (foo as Bar), returnsNormally);
  expect(() => (d as Bar), returnsNormally);

  // Type-checking and casting works regardless of the inheritance chain.
  var baz = Baz(42, 43);
  expect(baz is Foo, isTrue);
  expect(() => (baz as Foo), returnsNormally);
  expect(foo is Baz, isTrue);
  expect(() => (foo as Baz), returnsNormally);

  // BarCopy is the same JS class as Bar.
  var barCopy = BarCopy(42);
  expect(barCopy is Bar, isTrue);
  expect(() => (barCopy as Bar), returnsNormally);

  // JS object literal can be checked and casted with itself.
  expect(a is LiteralA, isTrue);
  expect(() => (a as LiteralA), returnsNormally);

  // Like class objects, casts are allowed between any object literals.
  expect(a is LiteralB, isTrue);
  expect(() => (a as LiteralB), returnsNormally);

  // Similarly, casts are allowed between any class objects and object literals.
  expect(foo is LiteralB, isTrue);
  expect(() => (foo as LiteralB), returnsNormally);
  expect(a is Foo, isTrue);
  expect(() => (a as Foo), returnsNormally);
}