/// <summary>
/// Call this method to create an instance representing the result of a failed operation.
/// </summary>
/// <param name="errors">All the detected errors</param>
/// <exception cref="ArgumentNullException">Throws ArgumentNullException when parameter errors is null</exception>
/// <returns>An instance representing the result of a failed operation.</returns>
public static OperationResult <TOutput, TError> CreateFailure(NonEmptySequence <TError> errors)
{
if (errors == null)
{
throw new ArgumentNullException(nameof(errors));
}
return(new OperationResult <TOutput, TError>(default, errors));
public void Error_Does_Not_Throw_When_Operation_Is_Failed_With_Several_Errors()
{
// ARRANGE
var errors = new NonEmptySequence <string>(new[] { "something bad happened!", "kaboom!" });
var target = OperationResult <string, string> .CreateFailure(errors);
// ACT
Assert.DoesNotThrow(() => _ = target.Error);
}
public void Error_Returns_First_Error_When_Operation_Is_Failed_With_Several_Errors()
{
// ARRANGE
var errors = new NonEmptySequence <string>(new[] { "something bad happened!", "kaboom!" });
var target = OperationResult <string, string> .CreateFailure(errors);
// ACT
var result = target.Error;
// ASSERT
Assert.AreEqual("something bad happened!", result);
}
public void Ctor_Creates_An_Enumerable_Instance()
{
// ARRANGE
var items = new[] { "foo", "bar" };
// ACT
var result = new NonEmptySequence <string>(items);
// ASSERT
Assert.IsNotNull(result);
CollectionAssert.AreEqual(new[] { "foo", "bar" }, result);
}
public void CreateFailure_Throws_When_Errors_Is_Null()
{
// ARRANGE
NonEmptySequence <string> nullSequence = null;
// ACT
var exception = Assert.Throws <ArgumentNullException>(() =>
OperationResult <string, string> .CreateFailure(nullSequence)
);
// ASSERT
Assert.IsNotNull(exception);
Assert.AreEqual("errors", exception.ParamName);
}
