Added tests for StandardDeviationCalculationHandler.cs

Raccoon.Ninja.Domain.Core.Tests/Calculators/Handlers/StandardDeviationCalculatorHandlerTests.cs

@@ -0,0 +1,94 @@
+using Raccoon.Ninja.Domain.Core.Calculators;
+using Raccoon.Ninja.Domain.Core.Calculators.Handlers;
+
+namespace Raccoon.Ninja.Domain.Core.Tests.Calculators.Handlers;
+
+public class StandardDeviationCalculatorHandlerTests
+{
+    private readonly StandardDeviationCalculatorHandler _sut = new ();
+
+    [Fact]
+    public void RunCalculation_ShouldReturnCorrectStandardDeviation_WithValidData()
+    {
+        // Arrange
+        var data = new CalculationData
+        {
+            GlucoseValues = new List<float> { 1, 2, 3, 4, 5 },
+            Average = 3
+        };
+
+        // Act
+        var result = _sut.Handle(data);
+
+        // Assert
+        result.StandardDeviation.Should().BeApproximately(1.4142f, 0.0001f);
+    }
+
+    [Fact]
+    public void RunCalculation_ShouldHandleSingleValue()
+    {
+        // Arrange
+        var data = new CalculationData
+        {
+            GlucoseValues = new List<float> { 10 },
+            Average = 10
+        };
+
+        // Act
+        var result = _sut.Handle(data);
+
+        // Assert
+        result.StandardDeviation.Should().Be(0);
+    }
+
+    [Fact]
+    public void RunCalculation_ShouldHandleNegativeValues()
+    {
+        // Arrange
+        var data = new CalculationData
+        {
+            GlucoseValues = new List<float> { -10, -20, 0, 5, 10 },
+            Average = -3
+        };
+
+        // Act
+        var result = _sut.Handle(data);
+
+        // Assert
+        result.StandardDeviation.Should().BeApproximately(10.7703f, 0.0001f);
+    }
+
+    [Fact]
+    public void RunCalculation_ShouldHandleMixedValues()
+    {
+        // Arrange
+        var data = new CalculationData
+        {
+            GlucoseValues = new List<float> { 5, 7, -3, 2, 8, -1 },
+            Average = 3
+        };
+
+        // Act
+        var result = _sut.Handle(data);
+
+        // Assert
+        result.StandardDeviation.Should().BeApproximately(4.0414f, 0.0001f);
+    }
+
+    [Fact]
+    public void RunCalculation_ShouldHandleSameValues()
+    {
+        // Arrange
+        var data = new CalculationData
+        {
+            GlucoseValues = new List<float> { 5, 5, 5, 5, 5 },
+            Average = 5
+        };
+
+        // Act
+        var result = _sut.Handle(data);
+
+        // Assert
+        result.StandardDeviation.Should().Be(0);
+    }
+}