csharp-tunit Skill (awesome-copilot) for Claude Code: What It Does and How to Install It

• Separate [ProjectName].Tests project with TUnit and TUnit.Assertions

  TUnit needs .NET 8.0 or higher. Tests run with dotnet test.

  Runs code · Project setup

• [Test] attribute, no class attributes, Arrange-Act-Assert

  Names tests MethodName_Scenario_ExpectedBehavior and uses [Before(Test)] and [After(Test)] for setup and teardown.

  Try: “Write TUnit tests for my Calculator class”

  Write · Test structure

• One behavior per test, awaited Assert.That assertions

  Tests should be independent; [DependsOn] is there when they cannot be.

  Write · Standard tests

• [Arguments], [MethodData], [ClassData], ITestDataSource

  [Arguments] is the equivalent of xUnit's [InlineData].

  Write · Data-driven tests

• await Assert.That(...) with IsEqualTo, Contains, Throws, And and Or

  All assertions are asynchronous and must be awaited.

  Write · Assertions

• [Repeat], [Retry], [ParallelLimit<T>], [Skip], [Timeout]

  Also [DependsOn] and custom attributes.

  Write · Advanced features

• Parallel by default; [NotInParallel] to opt out

  Tests within the same class run sequentially by default.

  Write · Parallel execution

• Maps [Fact], [Theory], [InlineData], [MemberData] and asserts to TUnit

  9 replacement rules, such as [Fact] to [Test] and IClassFixture<T> to [Before(Class)] and [After(Class)].

  Write · Migration from xUnit

Watch out for

• It edits your test code

  Claude writes and changes test classes and the test project in your repo. Review the diff and run the tests yourself before you commit. github.com

• The plugin route also adds an agent and 8 other skills

  The plugin.json lists 9 skills and one agent, expert-dotnet-software-engineer. That agent's file lists tools such as runCommands, runTasks, edit/editFiles and fetch. Use a folder route or the skills CLI if you want only csharp-tunit. github.com