ArgumentException and subclasses should provide ParamName property

[migig]

If I check for a null argument:

WithExceptionOnFailure<ArgumentNullException>().Requires(foo, nameof(foo)).IsNotNull();

In testing, one can assert that it throws an ArgumentNullException, and also get the name of the invalid argument from exception.ParamName.

But, for ArgumentException, this doesn't work as expected, because exception.ParamName == null. (Unsure whether the same is true for ArgumentOutOfRangeException.)

So: when library throws an ArgumentNullException it passes the paramName argument, but it doesn't do that when throwing ArgumentException.

This makes some testing quite difficult. When one is testing some method which has multiple arguments any of which could be invalid, the ParamName property tells you WHICH ONE was the problem.

I've looked into the source, but I admit I don't understand how the throwing works, and where to make this fix.

[migig]

Test case:

var foo = "";
WithExceptionOnFailure<ArgumentException>().Requires(foo, nameof(foo)).IsNotEmpty()

In the exception that will be thrown:

exception.ParamName == null