Microsoft.Identity.Web - Implement C# 8.0 nullable standard

[ghost]

Even if the project is not C# 8.0, consider implementing the nullable standard by suffixing ? to all parameters and returns that may be NULL.

This will be a breaking changing internal to the library & to consuming code. Therefore, consider publishing the changes only during a major cycle.

[jmprieur]

@sujayvsarma can you be more specific about which parameters you'd want to be null?

[ghost]

Not that I would want to make null, but it creates a distinction between what the code would consider to maybe null or will never be null.

For example, in Microsoft.Identity.Web > TokenAcquisition.cs, line 165, you are checking if the parameter scopes is null. If the GetAccessTokenOnBehalfOfUserAsync expects to receive scopes as null sometime, it would define its signature as:

public async Task<string> GetAccessTokenOnBehalfOfUserAsync(
            IEnumerable<string>? scopes,
            string tenant = null)

Note the ? at the end of the IEnumerable<string>. That says to the calling developer that scopes could be passed in as NULL. Otherwise it tells them that scopes cannot be NULL there.

Simply add this to your Microsoft.Identity.Web.csproj and watch Visual Studio make those suggestions for you:

<LangVersion>8.0</LangVersion>
<Nullable>enable</Nullable>

Fixing those suggestions is a breaking change.

[ghost]

Fyi, I have managed to implement these suggestions and managed to remove & clean up some code as well. If you're interested, I'll hook up a PR or send you the zip somewhere ?

[jmprieur]

Sure, @sujayvsarma, feel free to propose a PR.

[jennyf19]

issue tracked in microsoft identity web repo: AzureAD/microsoft-identity-web#15