bunit-test-migration

bUnit Test Migration Skill (Beta → 2.x)

This skill provides guidance for migrating test files from the deprecated bUnit 1.0.0-beta-10 API to bUnit 2.5.3 stable API. Use this when you encounter test files using the old TestComponentBase, <Fixture>, or <SnapshotTest> patterns.

When to Apply

Apply this skill when a .razor test file contains any of these patterns:

• @inherits TestComponentBase
• <Fixture Test="...">
• <ComponentUnderTest>
• <SnapshotTest>
• void MethodName(Fixture fixture)

Transformation Rules

1. Change Inheritance

- @inherits TestComponentBase
+ @inherits BunitContext

2. Remove Wrapper Elements

Remove these XML elements entirely (keep only the component inside):

- <Fixture Test="TestName">
-     <ComponentUnderTest>
          <MyComponent Parameter="value" />
-     </ComponentUnderTest>
- </Fixture>

3. Convert Test Methods

- void TestMethodName(Fixture fixture)
+ [Fact]
+ public void ComponentName_Scenario_ExpectedResult()

4. Replace Component Access

- var cut = fixture.GetComponentUnderTest();
+ var cut = Render(@<MyComponent Parameter="value" />);

5. Convert Snapshot Tests

- <SnapshotTest Description="renders correctly">
-     <TestInput>
-         <MyComponent />
-     </TestInput>
-     <ExpectedOutput>
-         <div>expected html</div>
-     </ExpectedOutput>
- </SnapshotTest>
+ [Fact]
+ public void MyComponent_Default_RendersCorrectly()
+ {
+     var cut = Render(@<MyComponent />);
+     cut.MarkupMatches(@<div>expected html</div>);
+ }

Complete Example

Before

@inherits TestComponentBase

<Fixture Test="ShouldClickButton">
    <ComponentUnderTest>
        <Button OnClick="OnClick">Click me</Button>
    </ComponentUnderTest>
</Fixture>

@code {
    int ClickCount = 0;

    void ShouldClickButton(Fixture fixture)
    {
        var cut = fixture.GetComponentUnderTest();

        cut.Find("button").Click();

        ClickCount.ShouldBe(1);
    }

    void OnClick() => ClickCount++;
}