private IEnumerable <Markdown.IElement> Step4DocumentTheRequirement()
{
yield return(new Markdown.Header3("Fourth step: document the requirement"));
yield return(new Markdown.Paragraph("TODO"));
yield return(new Markdown.Code(ClassReader.ReadMethodBody(nameof(this.Step4Sample))));
}
private IEnumerable <Markdown.IElement> Sample1()
{
var balance = -10;
this.Act(() =>
this.QuickSample1(balance)
)
.AssertException($"balance cannot be < 0 and actually is {balance}");
yield return(new Markdown.Code(ClassReader.ReadMethodBody(nameof(this.QuickSample1))));
}
private IEnumerable <Markdown.IElement> Sample2()
{
TransactionType transactionType = TransactionType.OnlinePayment;
double? onlinePaymentLimit = 10;
double paymentAmount = 11;
this.Act(() =>
this.QuickSample2(transactionType, onlinePaymentLimit, paymentAmount)
)
.AssertException($"Online Payment Amount ({paymentAmount}) exceeds the Online Payment Limit ({onlinePaymentLimit})");
yield return(new Markdown.Code(ClassReader.ReadMethodBody(nameof(this.QuickSample2))));
}
private IEnumerable <Markdown.IElement> Step2MakeItWorking()
{
yield return(new Markdown.Header3("Second step: make it working"));
yield return(new Markdown.Paragraph("When time comes you should implement the business requirement. It might look like that:"));
var withdrawLimit = 100;
var withdrawAmount = 110;
this.Act(() =>
this.Step2Sample(withdrawLimit, withdrawAmount)
)
.AssertException($"Withdraw Amount ({withdrawAmount}) exceeds the Withdraw Limit ({withdrawLimit})");
yield return(new Markdown.Code(ClassReader.ReadMethodBody(nameof(this.Step2Sample))));
yield return(new Markdown.Paragraph("This sample is simplified for sure, but remember that simple solutions are the best."));
}
private IEnumerable <Markdown.IElement> Step1GatherRequirements()
{
yield return(new Markdown.Header3("First step: business requirements gathering"));
yield return(new Markdown.Paragraph("Quite often you might hear during analysis phase of your project such words:"));
yield return(new Markdown.Quote("When withdraw limit is set, withdrawn amount cannot exceed the limit"));
yield return(new Markdown.Paragraph("When you hear such sentence just start your development by writing it down like that:"));
this.Act(() =>
this.Step1Sample()
)
.AssertException("NOT IMPLEMENTED");
yield return(new Markdown.Code(ClassReader.ReadMethodBody(nameof(this.Step1Sample))));
yield return(new Markdown.Paragraph("This will throw `NotImplementedException` for sure. But we have not finished our job yet."));
}
private IEnumerable <Markdown.IElement> Step3IntroduceDedicatedException()
{
yield return(new Markdown.Header3("Third step: introduce dedicated exception"));
yield return(new Markdown.Paragraph($"I like this step very much. Instead of using some generic exception thrown by" +
$" `{nameof(Business.Requirement.Throws)}()` method introduce your own meaningful exception:"));
var withdrawLimit = 100;
var withdrawAmount = 110;
this.Act(() =>
this.Step3Sample(withdrawLimit, withdrawAmount)
)
.AssertException($"Withdraw Amount ({withdrawAmount}) exceeds the Withdraw Limit ({withdrawLimit})");
yield return(new Markdown.Code(ClassReader.ReadMethodBody(nameof(this.Step3Sample))));
yield return(new Markdown.Paragraph("Introducing dedicated exception is not always needed. " +
"It allows you to handle (catch) some situations properly. " +
"It also gives you a way to derive all thrown business exceptions from your own base `Exception` class."));
}
public static string?Read(string method)
{
return(ClassReader.ReadMethodBody(method));
}