Test refactoring

TestHelper.cs

// This class helps reduce the amount of code in each test.

private class TestHelper
{
	private DateTime StartTime;
	private Enums.MetricStorageInterval DataGranularity;
	private List<ceQryDashboardGadgetDataBO> Data1;
	private List<ceQryDashboardGadgetDataBO> Data2;
	private List<ExpectedResult> ExpectedResults;

	public TestHelper(string startTime, Enums.MetricStorageInterval dataGranularity)
	{
		this.StartTime = DateTime.Parse(startTime);
		this.DataGranularity = dataGranularity;
		this.Data1 = new List<ceQryDashboardGadgetDataBO>();
		this.Data2 = new List<ceQryDashboardGadgetDataBO>();
		this.ExpectedResults = new List<ExpectedResult>();
	}

	public void AddToSeries1(decimal value, double minutesFromStartTime)
	{
		this.Data1.Add(this.CreateData(value, minutesFromStartTime));
	}

	public void AddToSeries2(decimal value, double minutesFromStartTime)
	{
		this.Data2.Add(this.CreateData(value, minutesFromStartTime));
	}

	public void AddExpectedResult(decimal? value1, decimal? value2, double minutesFromStartTime)
	{
		this.ExpectedResults.Add(new ExpectedResult
			{
				Time = this.StartTime.AddMinutes(minutesFromStartTime),
				Value1 = value1,
				Value2 = value2
			});
	}

	public void RunTest(string time)
	{
		var test = new InteractiveBarChartGadget.PartialHoursProvider(
			new InteractiveBarChartGadget.DataSeries { Data = this.Data1.ToArray() },
			new InteractiveBarChartGadget.DataSeries { Data = this.Data2.ToArray() },
			this.DataGranularity,
			this.StartTime);

		var results = test.GetDataFor(DateTime.Parse(time)).ToArray();

		results.Length.ShouldEqual(this.ExpectedResults.Count, "Wrong number of results");

		int index = 0;
		this.ExpectedResults
			.Zip(results, (e, a) => new { Expected = e, Actual = a, Index = index++ })
			.ForEach(x => this.VerifyResult(x.Expected, x.Actual, x.Index));
	}

	private ceQryDashboardGadgetDataBO CreateData(decimal value, double minutesFromStartTime)
	{
		return new ceQryDashboardGadgetDataBO(
			value: value,
			storetime: this.StartTime.AddMinutes(minutesFromStartTime));
	}

	private void VerifyResult(ExpectedResult expected, InteractiveBarChartGadget.PartialHourDataItem actual, int index)
	{
		actual.Time.ShouldEqual(expected.Time, String.Format("Wrong time at index {0}", index));
		actual.Value1.ShouldEqual(expected.Value1, String.Format("Wrong value 1 at index {0}", index));
		actual.Value2.ShouldEqual(expected.Value2, String.Format("Wrong value 2 at index {0}", index));
	}

	private class ExpectedResult
	{
		public DateTime Time { get; set; }
		public decimal? Value1 { get; set; }
		public decimal? Value2 { get; set; }
	}
}

TestVersion1.cs

[TestClass]
public class PartialHoursProviderTests
{
	// This test has a lot of code in it. I don't want to start copying this around
	// to all the other tests.

	[TestMethod]
	public void BarChart_PartialHours_Half_Value1Only()
	{
		var startTime = DateTime.Parse("7/2/2013 15:00");
		var dataSeries = new InteractiveBarChartGadget.DataSeries
		{
			Data = new[]
			{
				new ceQryDashboardGadgetDataBO(value: 10, storetime: startTime),
				new ceQryDashboardGadgetDataBO(value: 20, storetime: startTime.AddMinutes(30)),
				new ceQryDashboardGadgetDataBO(value: 30, storetime: startTime.AddMinutes(60)),
				new ceQryDashboardGadgetDataBO(value: 40, storetime: startTime.AddMinutes(90))
			}
		};

		var test = new InteractiveBarChartGadget.PartialHoursProvider(
			dataSeries,
			null,
			Enums.MetricStorageInterval.HalfHourly,
			startTime);

		var results = test.GetDataFor(startTime).ToArray();

		results.Length.ShouldEqual(2, "Wrong number of results");
		this.VerifyResult(0, startTime, 10, null, results);
		this.VerifyResult(1, startTime.AddMinutes(30), 20, null, results);
	}
}

TestVersion2.cs

[TestClass]
public class PartialHoursProviderTests
{
	// This test uses TestHelper and therefore contains less code.
	// I could have omitted all the parameter names, but I think it's more understandable this way.

	[TestMethod]
	public void BarChart_PartialHours_Half_Value1Only()
	{
		var helper = new TestHelper("7/2/2013 15:00", Enums.MetricStorageInterval.HalfHourly);

		helper.AddToSeries1(value: 10, minutesFromStartTime: 0);
		helper.AddToSeries1(value: 20, minutesFromStartTime: 30);
		helper.AddToSeries1(value: 30, minutesFromStartTime: 60);
		helper.AddToSeries1(value: 40, minutesFromStartTime: 90);

		helper.AddExpectedResult(value1: 10, value2: null, minutesFromStartTime: 0);
		helper.AddExpectedResult(value1: 20, value2: null, minutesFromStartTime: 30);

		helper.RunTest("7/2/2013 15:00");
	}
}