public async Task ShouldReturnNullIfAtEnd()
{
var records = RecordCreator.CreateRecords(5);
var cursor = new ListBasedRecordCursor(new[] { "key0" }, () => records);
// [0, 1, 2, 3]
await cursor.FetchAsync();
await cursor.FetchAsync();
await cursor.FetchAsync();
await cursor.FetchAsync();
var record = await cursor.PeekAsync();
record.Should().NotBeNull();
record[0].As <string>().Should().Be("record4:key0");
var moveNext = await cursor.FetchAsync();
moveNext.Should().BeTrue();
record.Should().NotBeNull();
record[0].As <string>().Should().Be("record4:key0");
record = await cursor.PeekAsync();
record.Should().BeNull();
}
public async Task ShouldBeTheSameWithEnumeratorMoveNextCurrent()
{
var records = RecordCreator.CreateRecords(2);
var cursor = new ListBasedRecordCursor(new[] { "key0" }, () => records);
IRecord record;
bool hasNext;
for (int i = 0; i < 2; i++)
{
record = await cursor.PeekAsync();
record.Should().NotBeNull();
record[0].As <string>().Should().Be($"record{i}:key0");
hasNext = await cursor.FetchAsync();
hasNext.Should().BeTrue();
// peeked record = current
cursor.Current[0].As <string>().Should().Be($"record{i}:key0");
}
record = await cursor.PeekAsync();
record.Should().BeNull();
hasNext = await cursor.FetchAsync();
hasNext.Should().BeFalse();
}
public async Task ShouldReturnNextRecordWithoutMovingCurrentRecord()
{
var records = RecordCreator.CreateRecords(5);
var cursor = new ListBasedRecordCursor(new[] { "key1" }, () => records);
var record = await cursor.PeekAsync();
record.Should().NotBeNull();
record[0].As <string>().Should().Be("record0:key0");
// not moving further no matter how many times are called
record = await cursor.PeekAsync();
record.Should().NotBeNull();
record[0].As <string>().Should().Be("record0:key0");
}