tests/language/cascade_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";

// Test cascades.

class A {
  int x;
  int y;

  A(this.x, this.y);

  A setX(int x) { this.x = x; return this; }

  void setY(int y) { this.y = y; }

  Function swap() {
    int tmp = x;
    x = y;
    y = tmp;
    return this.swap;
  }

  void check(int x, int y) {
    Expect.equals(x, this.x);
    Expect.equals(y, this.y);
  }

  operator[](var i) {
    if (i == 0) return x;
    if (i == 1) return y;
    if (i == "swap") return this.swap;
    return null;
  }

  int operator[]=(int i, int value) {
    if (i == 0) {
      x = value;
    } else if (i == 1) {
      y = value;
    }
  }

  /**
   * A pseudo-keyword.
   */
  import() {
    x++;
  }
}

main() {
  A a = new A(1, 2);
  a..check(1, 2)
   ..swap()..check(2, 1)
   ..x = 4..y = 9..check(4, 9)
   ..setX(10)..check(10, 9)
   ..y = 5..check(10, 5)
   ..swap()()()..check(5, 10)
   ..[0] = 2..check(2, 10)
   ..setX(10).setY(3)..check(10, 3)
   ..setX(7)["swap"]()..check(3, 7)
   ..import()..check(4, 7)
   ..["swap"]()()()..check(7, 4);
  a.check(7,4);
  a..(42);  /// 01: compile-time error
  a..37;  /// 02: compile-time error
  a.."foo";  /// 03: compile-time error
}