How do you pass parameters to tests in xUnit?

Short answer: Using [Theory] and data attributes like [InlineData]: [Theory] [InlineData(2, 3, 5)] [InlineData(10, 20, 30)] public void Add_ReturnsSum(int a, int b, int expected) { var calculator = new Calculator(); var result = calculator.Add(a, b); Assert.Equal(expected, result); }

Example code

Using [Theory] and data attributes like [InlineData]: [Theory] [InlineData(2, 3, 5)] [InlineData(10, 20, 30)] public void Add_ReturnsSum(int a, int b, int expected)
{
var calculator = new Calculator();
var result = calculator.Add(a, b); Assert.Equal(expected, result); }

Real-world example (ShopNest)

ShopNest unit tests cover pricing and discount rules so a bad coupon change fails in CI before customers see it.

Say this in the interview

1. Define — one clear sentence (the short answer above).
2. Example — relate it to a project like ShopNest or your real work.
3. Trade-off — when you would not use it.