pomma89 / thrower

Fully managed library providing convenience methods to perform argument checks.

Thrower

Fully managed library providing convenience methods to perform argument checks.

Project repository has been moved to GitLab:

https://gitlab.com/pommalabs/thrower

thrower's Issues

Resharper warning "Possible multiple enumeration of IEnumerable" when validating enumerable parameters

I've been using this library for my guard clauses for a while, and I quite like it. However, I've recently started using R# and it's causing me to see (and have to suppress) a number of warnings about potential multiple enumerations when I'm using validations like Raise.ArgumentNullException.IfIsNull(someEnumerableParameter);

This is easy to fix - all that's needed is to add [NoEnumeration] from JetBrains.Annotations to any parameters in externally-accessible methods that can accept enumerable parameters, e.g.

public void IfIsNull<TArg>([NoEnumeration] TArg argument)
{
    if (ReferenceEquals(argument, null))
    {
        throw new ArgumentNullException();
    }
}

I'd do this myself and submit a pull request, but for some reason your project literally crashes Visual Studio 2017 every time I try to open it (not sure what's up with that).

IfIsNull does not handle Nullable<T> type

Raise ArgumentNullException if an instance of that type has no value.

Localization of default messages.

Would be nice to localize default messages.

It can be done with resources or default .NET messages (they uses resources anyway).

There is no documentation for exceptions of the IndexOutOfRangeExceptionHandler methods.

JetBrains Annotations: Part II

Thanks again for the annotating your methods with [NoEnumeration]. If possible, I'd like to expand on that to further support integration with Resharper.

One improvement that would be really nice would be to annotate the null guard methods, like this:

[ContractAnnotation("argument:null => halt")]
public void IfIsNull<TArg>(TArg argument, string argumentName, string message = null)
{
    // ...
}

For methods that only take a single parameter, the contract can be simplified:

[ContractAnnotation("null => halt")]
public void IfIsNull<TArg>(TArg argument)
{
    // ...
}

I'm still unable to open the Pommalabs.Thrower solution reliably without Visual Studio crashing, so I can't submit a pull request. However, I've tested these changes with simple analogs of some of your methods:

Can I pass in multiple parameters?

First of all, very nicely done!

I want to be able to pass in multiple parameters. Here is my use case...

if (!File.Exists(pdfPath)) throw new FileNotFoundException("PDF file not found" pdfPath);

I want to change this to ...

Raise<FileNotFoundException>.If(!File.Exists(pdfPath), "PDF file not found", pdfPath);

I can't find a way to pass in the pdfpath as the third parameter so it will be included as the second parameter of the FileNotFoundException. Is this possible?

Method to check value for Guid.Empty.