Test Data

The concept

Automated capturing of test data sets you free from typing test data manually and/or maintain test infrastructure setup. It is intended to reduce test maintenance costs.

Automated test data capture is core concept that is needed to support data-driven testing within Tecture.

How to capture data

Trace does that when you do tracing. That is why it is bad idea to call BeginTrace/EndTrace in production code.

After calling EndTrace, Trace instances embrace copies (deep clones) of all the results of the queries made through Tecture infrastructure. This circumstance allows to persist query results and reproduce them without external infrastructure. The most efficient way to store query results is... C# code. It allows to maintain compile-time checks of the test data and brings unit testing experience on the new level.

How to serialize test data into C# code

As mentioned above, data itself is already contained within Trace instance. Some tooling needed to extract it from there and turn into C# code. In order to do that you have to install Reinforced.Tecture.Testing NuGet package. Test data serialization capabilities are not included into core because they use Roslyn for code generation whether Tecture core keeps 0-dependency.

> Install-Package Reinforced.Tecture.Testing

This package supplies 2 extension methods for Trace:

• GenerateTestData: serializes data from captured queries into C# code. Explained below.
• GenerateUnitTest: serializes commands captured within Trace into validation code. Explained here.

Generate test data

Use following code to generate test data:

Trace t = _tecture.EndTrace();
var output = t.GenerateTestData("MyTestData", "Namespace.Of.My.Tests");
output.ToFile(@"Full\Path\To\Code\File.cs");

It will generate File.cs within Full\Path\To\Code\ folder.

Here is example of test data class for random business logic:

using System;
using System.Collections;
using System.Collections.Generic;
using Reinforced.Tecture.Testing.Data;
using Reinforced.Samples.ToyFactory.Logic.Warehouse.Entities;

namespace Namespace.Of.My.Tests
{
		class MyTestData : CSharpTestData
		{
			private Boolean GetEntry_1()
			{ 
				return false;
			}

			private Int32 GetEntry_2()
			{ 
				return 42;
			}

			private MeasurementUnit GetEntry_3()
			{ 
				var v1 = New<MeasurementUnit>();
				Set(v1, x=>x.Id, 42);
				Set(v1, x=>x.ShortName, @"kG");
				Set(v1, x=>x.Name, @"Kilograms");
				return v1;
			}

			public override IEnumerable<ITestDataRecord> GetRecords()
			{ 
				yield return new TestDataRecord<Boolean>(GetEntry_1()) { 
					Hash = @"OrmQuery_AB78B1DAADDAD273C885641045DBA4575D5FF2948319913F64C58E6FC40F215",
					Description = @"check unit existence"
				};
				yield return new TestDataRecord<Int32>(GetEntry_2()) { 
					Hash = @"ORM_AdditionPK_1",
					Description = @"ORM Addition PK retrieval"
				};
				yield return new TestDataRecord<MeasurementUnit>(GetEntry_3()) { 
					Hash = @"OrmQuery_733639199A5697167B201F9165F5D2487D9588D52EC594686EF5C98F2D619B",
					Description = @"Get MeasurementUnit by Id #42 (required)"
				};
			}

		}
}

Use test data

In order to mock all the following queries with generated test data, you must tell TectureBuilder to use generated test data class (yes, for number of reasons it has to be done within integration stage:

var tb = new TectureBuilder();
// ...channels configuration...
tb.WithTestData(new MyTestData());
var tecture = tb.Build();

That's all. All the queries done through this tecture instace will be redirected to test data.

Customization

You can substitute values form particular query result that test generator will embed into resulting code. Like this:

Trace t = _tecture.EndTrace();

var output = t.GenerateTestData("ClassWithTestData", "Namespace.Of.My.Tests",
                x => x.WithHijack(d =>
                  {
                      d.For<Product>().Hijack(x => x.Name, x => "Fake product name");
                  }));
				  
output.ToFile(@"Full\Path\To\Code\File.cs");

This will make test generator to embed "Fake product name" instead of actual data in Name property for every Product that appears in query results.