LibTest/core/Iterable/takeWhile_A01_t01.test.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 abstract Iterable<E> takeWhile(bool test(E value))
 * Returns an Iterable that stops once test is not satisfied anymore.
 * @description Checks that all first elements that satisfy test are retained, and
 * elements after that, are skipped.
 * @author kaigorodov
 */
import "../../../Utils/expect.dart"	;

void check(List a0, bool test(var element)) {
  Iterator it0=a0.iterator;
  Iterable a=a0.takeWhile(test);
  Iterator it=a.iterator;
  
  // check that the beginning of a0 is identical to a
  bool hasNext0=it0.moveNext();
  int len=0;
  for (;;) {
    bool hasNext=it.moveNext();
    if (!hasNext) break;
    Expect.isTrue(test(it0.current));
    Expect.equals(it0.current, it.current);
    len++;
    hasNext0=it0.moveNext();
  }
  Expect.equals(a.length, len);

  // count the rest
  int skipCount=0;
  while (hasNext0) {
    skipCount++;
    hasNext0=it0.moveNext();
  }

  Expect.equals(a0.length, len+skipCount);
}

main() {
  List a0=[1,3,7,4,5,6];
  check(a0, (var element)=>element==1);
  check(a0, (var element)=>true);
  check(a0, (var element)=>false);
  check(a0, (var element)=>element>4);
  check(a0, (var element)=>element<4);
  check(a0, (var element)=>element==4);
}