/// <summary>
/// Checks whether the value contained in the IEnsureArg instance is null or contains no
/// items. If it is null then an ArgumentNullException will be thrown. If the collection is
/// empty then an ArgumentException will be thrown.
/// </summary>
/// <typeparam name="T">The type of the value contained in the IEnsureArg instance.</typeparam>
/// <param name="ensureArg">
/// The IEnsureArg instance, usually created from an Ensure.Arg() call.
/// </param>
/// <param name="exceptionMessage">
/// Optional exception message to use if the null check fails. This exception message will
/// override the message supplied in the Ensure.Arg() call, if any.
/// </param>
/// <returns>The ensureArg instance.</returns>
/// <exception cref="System.ArgumentNullException">ensureArg.Value is null.</exception>
/// <exception cref="System.ArgumentException">
/// ensureArg.Value contain no items in the collection.
/// </exception>
public static IEnsureArg <IEnumerable <T> > IsNotNullOrEmpty <T>(
this IEnsureArg <IEnumerable <T> > ensureArg,
string exceptionMessage = null)
{
ensureArg.IsNotNull(exceptionMessage);
if (ensureArg.Value.IsNullOrEmpty())
{
ensureArg.ThrowArgumentException(exceptionMessage);
}
return(ensureArg);
}
public void When_IsNotNull_is_called_it_returns_the_EnsureArg_created_from_Ensure_Arg()
{
// Arrange.
object value = new object();
IEnsureArg <object> ensureArg = Ensure.Arg(value);
// Act.
IEnsureArg <object> returnedEnsureArg = ensureArg.IsNotNull();
// Assert.
ensureArg.Should().BeSameAs(returnedEnsureArg);
}
/// <summary>
/// Checks whether the value contained in the IEnsureArg instance is not null, empty, or
/// consists only of white-space characters. If it is null then an ArgumentNullException will
/// be thrown. If the string is empty or contains only white-space characters then an
/// ArgumentException will be thrown.
/// </summary>
/// <param name="ensureArg">
/// The IEnsureArg instance, usually created from an Ensure.Arg() call.
/// </param>
/// <param name="exceptionMessage">
/// Optional exception message to use if the null check fails. This exception message will
/// override the message supplied in the Ensure.Arg() call, if any.
/// </param>
/// <returns>The ensureArg instance.</returns>
/// <exception cref="System.ArgumentNullException">ensureArg.Value is null.</exception>
/// <exception cref="System.ArgumentException">
/// ensureArg.Value is an empty string ("") or only contains white-space characters.
/// </exception>
public static IEnsureArg <string> IsNotNullOrWhiteSpace(
this IEnsureArg <string> ensureArg,
string exceptionMessage = null)
{
ensureArg.IsNotNull(exceptionMessage);
if (string.IsNullOrWhiteSpace(ensureArg.Value))
{
ensureArg.ThrowArgumentException(exceptionMessage);
}
return(ensureArg);
}
public void When_Ensure_Arg_is_called_with_a_null_argument_name()
{
// Arrange.
object testObject = null;
IEnsureArg <object> ensureArg = Ensure.Arg(testObject, null);
// Act.
Action action = () =>
ensureArg.IsNotNull();
// Assert.
ensureArg.ArgumentName.Should().Be(null);
action.ShouldThrow <ArgumentNullException>()
.And.ParamName.Should().BeNull();
}
