blob: 3750459dd20d13c30ab0c183656659e4d270cfa8 [file] [log] [blame]
// 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 Iterable expand(Iterable f(E element))
/// Expands each element of this Iterable into zero or more elements.
/// The resulting Iterable runs through the elements returned by f for each
/// element of this, in iteration order.
/// The returned Iterable is lazy, and calls f for each element of this every
/// time it's iterated.
/// @description Checks that the function [f] is called for every element of the
/// list.
/// Checks that resulting Iterable will run through the elements returned by f
/// for each element of this
/// @author kaigorodov
/// @author
library expand_A01_t01;
import "../../../Utils/expect.dart";
test(Iterable create([Iterable content])) {
void checkCount(Iterable a) {
int count = 0;
Iterable expanded = a.expand((element) {
Expect.equals(a.elementAt(count), element);
return [element, element];
Expect.equals(a.length * 2, expanded.length);
// It's important to call expanded exactly once (the string above) before
// this check. Otherwise count will have wrong value because returned
// Iteratable is lazy
Expect.equals(count, a.length);
checkCount(create([1, 2]));
checkCount(create([1, 2, 2]));
checkCount(create([1, 2, 2, 3]));