mirror of
https://github.com/dart-lang/sdk
synced 2024-11-02 12:24:24 +00:00
b101a7d002
Change-Id: Ib33169c3e0ffc870915c189404074a1dea472546 Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/196548 Reviewed-by: Bob Nystrom <rnystrom@google.com> Commit-Queue: Leaf Petersen <leafp@google.com>
74 lines
2.7 KiB
Dart
74 lines
2.7 KiB
Dart
// Copyright (c) 2013, 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.
|
|
|
|
// @dart = 2.9
|
|
|
|
import "package:expect/expect.dart";
|
|
|
|
main() {
|
|
void test(expectedList, generatedIterable) {
|
|
Expect.equals(expectedList.length, generatedIterable.length);
|
|
Expect.listEquals(expectedList, generatedIterable.toList());
|
|
}
|
|
|
|
test([], new Iterable.generate(0));
|
|
test([0], new Iterable.generate(1));
|
|
test([0, 1, 2, 3, 4], new Iterable.generate(5));
|
|
test(["0", "1", "2", "3", "4"], new Iterable.generate(5, (x) => "$x"));
|
|
test([2, 3, 4, 5, 6], new Iterable.generate(7).skip(2));
|
|
test([0, 1, 2, 3, 4], new Iterable.generate(7).take(5));
|
|
test([], new Iterable.generate(5).skip(6));
|
|
test([], new Iterable.generate(5).take(0));
|
|
test([], new Iterable.generate(5).take(3).skip(3));
|
|
test([], new Iterable.generate(5).skip(6).take(0));
|
|
|
|
// Test types.
|
|
|
|
Iterable<int> it = new Iterable<int>.generate(5);
|
|
Expect.isTrue(it is Iterable<int>);
|
|
Expect.isTrue(it.iterator is Iterator<int>);
|
|
Expect.isTrue(it is! Iterable<String>);
|
|
Expect.isTrue(it.iterator is! Iterator<String>);
|
|
test([0, 1, 2, 3, 4], it);
|
|
|
|
Iterable<String> st = new Iterable<String>.generate(5, (x) => "$x");
|
|
Expect.isTrue(st is Iterable<String>);
|
|
Expect.isTrue(st.iterator is Iterator<String>);
|
|
Expect.isFalse(st is Iterable<int>);
|
|
Expect.isFalse(st.iterator is Iterator<int>);
|
|
test(["0", "1", "2", "3", "4"], st);
|
|
|
|
Expect.throws(() => new Iterable<String>.generate(5));
|
|
|
|
// Omitted generator function means `(int x) => x`, and the type parameters
|
|
// must then be compatible with `int`.
|
|
// Check that we catch invalid type parameters.
|
|
|
|
// Valid types:
|
|
Iterable<int> iter1 = new Iterable<int>.generate(5);
|
|
Expect.equals(2, iter1.elementAt(2));
|
|
Iterable<num> iter2 = new Iterable<num>.generate(5);
|
|
Expect.equals(2, iter2.elementAt(2));
|
|
Iterable<Object> iter3 = new Iterable<Object>.generate(5);
|
|
Expect.equals(2, iter3.elementAt(2));
|
|
Iterable<dynamic> iter4 = new Iterable<dynamic>.generate(5);
|
|
Expect.equals(2, iter4.elementAt(2));
|
|
|
|
// Invalid types:
|
|
Expect.throws(() => new Iterable<String>.generate(5));
|
|
Expect.throws(() => new Iterable<Null>.generate(5).elementAt(2)); //# 01: ok
|
|
Expect.throws(() => new Iterable<bool>.generate(5));
|
|
|
|
// Regression: https://github.com/dart-lang/sdk/issues/26358
|
|
var count = 0;
|
|
var iter = new Iterable.generate(5, (v) {
|
|
count++;
|
|
return v;
|
|
});
|
|
Expect.equals(0, count);
|
|
Expect.equals(2, iter.elementAt(2)); // Doesn't compute the earlier values.
|
|
Expect.equals(1, count);
|
|
Expect.equals(2, iter.skip(2).first); // Doesn't compute the skipped values.
|
|
Expect.equals(2, count);
|
|
}
|