public void FirstAsync_With_Empty_Must_Throw(int[] source)
{
// Arrange
var wrapped = Wrap
.AsAsyncValueEnumerable(source);
// Act
Func <ValueTask> action = async() => _ = await AsyncValueEnumerable
.FirstAsync <Wrap.AsyncValueEnumerable <int>, Wrap.AsyncEnumerator <int>, int>(wrapped);
// Assert
_ = action.Must()
.Throw <InvalidOperationException>()
.EvaluateTrue(exception => exception.Message == "Sequence contains no elements");
}
public async void FirstAsync_With_Empty_Must_Return_None(int[] source)
{
// Arrange
var wrapped = Wrap
.AsAsyncValueEnumerable(source);
// Act
var result = await AsyncValueEnumerable
.FirstAsync <Wrap.AsyncValueEnumerable <int>, Wrap.AsyncEnumerator <int>, int>(wrapped);
// Assert
_ = result.Must()
.BeOfType <Option <int> >()
.EvaluateTrue(option => option.IsNone);
}
public async ValueTask FirstAsync_With_ValidData_Must_Succeed(int[] source)
{
// Arrange
var wrapped = Wrap
.AsAsyncValueEnumerable(source);
var expected =
System.Linq.Enumerable.First(source);
// Act
var result = await AsyncValueEnumerable
.FirstAsync <Wrap.AsyncValueEnumerable <int>, Wrap.AsyncEnumerator <int>, int>(wrapped);
// Assert
_ = result.Must()
.BeEqualTo(expected);
}
public async ValueTask FirstAsync_With_ValidData_Must_Return_Some(int[] source)
{
// Arrange
var wrapped = Wrap
.AsAsyncValueEnumerable(source);
var expected =
System.Linq.Enumerable.First(source);
// Act
var result = await AsyncValueEnumerable
.FirstAsync <Wrap.AsyncValueEnumerable <int>, Wrap.AsyncEnumerator <int>, int>(wrapped);
// Assert
_ = result.Match(
value => value.Must().BeEqualTo(expected),
() => throw new Exception());
}