Language/12_Expressions/08_Throw_A03_t03.dart

/*
 * Copyright (c) 2011, 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 Evaluation of a throw expression of the form throw e; proceeds as follows:
 * The expression e is evaluated yielding a value v. If v evaluates to null, then a
 * NullThrownError is thrown. Otherwise, control is transferred to the nearest
 * dynamically enclosing exception handler, with the current exception set to v.
 * @description Checks that an expression statement of the form "throw e;" indeed raises an exception
 * and transfers control to the nearest enclosing exception handler if there is one.
 * @author rodionov
 * @reviewer iefremov
 */
import "../../Utils/expect.dart";

main() {
  bool flag = false;
  var ex = "";
  try {
    foo() {
      try {
        throw ex;
        Expect.fail("This code shouldn't be executed");
      } on int catch(i) {}
      Expect.fail("This code shouldn't be executed");
    }
    foo();
    Expect.fail("This code shouldn't be executed");
  } on int catch(i) {
  } catch (s, st) {
    flag = true;
    Expect.isTrue(identical(ex, s));
    Expect.isNotNull(st);
  }
  
  Expect.isTrue(flag, "The correct exception handler wasn't triggered");
}