
using Xunit;
namespace ConsoleApp {
    public class ProgramTests {
        [Fact(DisplayName = "Deposit throws NegativeDepositException for negative amount")]
        public void Deposit_ThrowsException_ForNegativeAmount()
        {
            var account = new BankAccount(100);
            var ex = Assert.Throws<NegativeDepositException>(() => account.Deposit(-5));
            Assert.Equal("Deposit amount cannot be negative.", ex.Message);
        }

        [Fact(DisplayName = "Balance does not change if NegativeDepositException is thrown")]
        public void Deposit_DoesNotChangeBalance_OnException()
        {
            var account = new BankAccount(200);
            try {
                account.Deposit(-10);
            } catch (NegativeDepositException) {
                // ignored
            }
            Assert.Equal(200, account.GetBalance());
        }

        [Fact(DisplayName = "Deposit adds positive amount to balance")]
        public void Deposit_AddsPositiveAmount()
        {
            var account = new BankAccount(50);
            account.Deposit(25);
            Assert.Equal(75, account.GetBalance());
        }
    }
}

ProgramTests.cs

Master the art of robust C# programming by learning how to handle, create, and debug exceptions. This hands-on course guides you through real-world error handling scenarios, from basic try-catch to custom exceptions and safe file operations.

Learn the basics of exceptions in C#, how to use try-catch blocks, and why error handling is crucial for robust applications.

Learn to create your own exception types and use guard clauses to prevent invalid states in your code.

Master techniques for validating user input and safely parsing data to prevent runtime errors.

Handle file operations safely and learn to debug exceptions using stack traces and refactoring techniques.

Challenge: Custom Exception for Business Rules

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