bdd-asynclisted

# bdd-async Behavior-Driven Development skill for TUnit. Describes observable business behavior using Given → When → Then. TUnit is the testing framework. ## Workflow ``` Business Requirement ↓ Identify Business Behavior ↓ Given → When → Then ↓ Write TUnit Test ↓ Run Test → Implement / Fix → Run Test → PASS ``` ## Step 1 — Understand the Business Requirement Before writing code: 1. Read the requirement. 2. Identify the actor. 3. Identify the initial context. 4. Identify the business action. 5. Identify the expected result. 6. Identify important business rules. 7. Identify relevant edge cases. 8. Inspect existing tests and domain language. Translate the requirement into a scenario. **Example:** ```gherkin Feature: Customer discount Scenario: Premium customer receives a discount Given the customer is premium When the customer purchases an item Then a 20% discount is applied ``` ## Step 2 — Create the TUnit Test Represent the scenario as a readable TUnit test. ```csharp [Test] public async Task PremiumCustomer_WhenPurchasingItem_Receives20PercentDiscount() { // Given var customer = Customer.CreatePremium(); var product = new Product(100m); // When var total = pricingService.CalculateTotal(customer, product); // Then await Assert.That(total).IsEqualTo(80m); } ``` Clearly expose Given / When / Then. Use comments when they improve readability — but not mechanically when code is already self-explanatory. ## Business Langu