ConfigureAwaitVSExtension

A Visual Studio extension that warn to configure an awaiter in await calls

⚠️ this branch is for VS2017 only ⚠️ if you want to try in VS2019 go to feature/vs-2019 branch

Motivation

We always forget the ConfigureAwait(...), so this extension warns us about this and fixes it! 😎 I made this project just for fun. I'm sure there are some edge cases that I didn't take into account Meanwhile, enjoy it! 😉

About the code

I used the Visual Studio Extensibility Template Analyzer with Code Fix (.NET Standard). In theory, this extension can be deployed as either a NuGet package or a VSIX extension. It was tested using Microsoft Visual Studio 2017 Version 15.9.11

The ConfigureAwaitAnalyzer

It only runs if there are no compilation errors. It analyzes the AwaitExpressionSyntax nodes and check if their expression (method call or variable) is of type ConfiguredTaskAwaitable. That's it.

The ConfigureAwaitAnalyzerCodeFixProvider

It modifies the AwaitExpressionSyntax's ExpressionNode in order to add the .ConfigureAwait([true|false]) expression nodes:

this way we make the fix. There are two code fixes: 'Add ConfigureAwait(false)' and 'Add ConfigureAwait(true)'

Todos

• Check edge cases like:

  • Await an already configured task (invoked as variable) :

    var task = MethodAsync().ConfigureAwait(false);
    var result = await task;  // <- this generates an unnecesary warning
                 ~~~~~~~~~~~

  • Await calls in Controller's Action in ASP.NET Core apps

    class HomeController : Controller 
    {
          public async Task<IActionAsync> GetData()
          {
              return Ok(await GetDataAsync()) // <- this generates an unnecesary warning
                        ~~~~~~~~~~~~~~~~~~~~
          }
    }

• Maybe do something smarter than just check the suffix on the string representation

• Allow user settings to:

  • activate/deactivate the extension
  • change if the extension should report Warnings or Errors

Useful links for development

• Creating a .NET Standard Roslyn Analyzer in Visual Studio 2017
• Starting to Develop Visual Studio Extensions
• How To Write a C# Analyzer and Code Fix
• Working with types in a Roslyn analyzer

Releases

If you want just the *.vsix file download it from the releases

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Coded by JJ - 2019

Thanks to @carlosbonillabirchman for telling me about this idea

Licensed under the MIT license