Add missing Arrange/Act/Assert comments and improve exception specificity in SkittleTests

[Copilot]

Applies consistency fixes to test methods in SkittleTests.cs by adding missing AAA pattern comments and improving exception type specificity.

Changes

• Test comments: Added //Arrange, //Act, and //Assert comments to CountSkittlesInA1CubicNullUnitTest() and CountSkittlesInACylinderWithNullUnitTest() for consistency with other tests in the class

• Exception specificity: Changed Assert.Throws<Exception> to Assert.Throws<ArgumentNullException> in CountSkittlesInANullUnitTest() and updated Calculator.GetCubicCmForVolume() to throw ArgumentNullException when unit is null/empty:

if (string.IsNullOrEmpty(unit))
{
    throw new ArgumentNullException(nameof(unit), "Unit cannot be null or empty.");
}

Original prompt

Please apply the following diffs and create a pull request.
Once the PR is ready, give it a title based on the messages of the fixes being applied.

[{"message":"Missing //Arrange comment for consistency with other test methods in the same class.","fixFiles":[{"filePath":"src/MandMCounter.Tests/SkittleTests.cs","diff":"diff --git a/src/MandMCounter.Tests/SkittleTests.cs b/src/MandMCounter.Tests/SkittleTests.cs\n--- a/src/MandMCounter.Tests/SkittleTests.cs\n+++ b/src/MandMCounter.Tests/SkittleTests.cs\n@@ -169,6 +169,7 @@\n         [TestMethod]\n         public void CountSkittlesInA1CubicNullUnitTest()\n         {\n+            //Arrange\n             string unit = null;\n             float height = 1;\n             float width = 1;\n"}]},{"message":"Missing //Act & Assert comment for consistency with other test methods in the same class.","fixFiles":[{"filePath":"src/MandMCounter.Tests/SkittleTests.cs","diff":"diff --git a/src/MandMCounter.Tests/SkittleTests.cs b/src/MandMCounter.Tests/SkittleTests.cs\n--- a/src/MandMCounter.Tests/SkittleTests.cs\n+++ b/src/MandMCounter.Tests/SkittleTests.cs\n@@ -174,6 +174,9 @@\n             float width = 1;\n             float length = 1;\n \n+            //Act\n+\n+            //Assert\n             Assert.Throws<Exception>(() => Calculator.CountSkittles(unit, height, width, length));\n         }\n \n"}]},{"message":"Missing //Arrange comment for consistency with other test methods in the same class.","fixFiles":[{"filePath":"src/MandMCounter.Tests/SkittleTests.cs","diff":"diff --git a/src/MandMCounter.Tests/SkittleTests.cs b/src/MandMCounter.Tests/SkittleTests.cs\n--- a/src/MandMCounter.Tests/SkittleTests.cs\n+++ b/src/MandMCounter.Tests/SkittleTests.cs\n@@ -216,6 +216,7 @@\n         [TestMethod]\n         public void CountSkittlesInACylinderWithNullUnitTest()\n         {\n+            //Arrange\n             string unit = null;\n             float height = 10;\n             float radius = 5;\n"}]},{"message":"Missing //Act & Assert comment for consistency with other test methods in the same class.","fixFiles":[{"filePath":"src/MandMCounter.Tests/SkittleTests.cs","diff":"diff --git a/src/MandMCounter.Tests/SkittleTests.cs b/src/MandMCounter.Tests/SkittleTests.cs\n--- a/src/MandMCounter.Tests/SkittleTests.cs\n+++ b/src/MandMCounter.Tests/SkittleTests.cs\n@@ -216,10 +216,12 @@\n         [TestMethod]\n         public void CountSkittlesInACylinderWithNullUnitTest()\n         {\n+            //Arrange\n             string unit = null;\n             float height = 10;\n             float radius = 5;\n \n+            //Act & Assert\n             Assert.Throws<Exception>(() => Calculator.CountSkittles(unit, height, radius));\n         }\n \n"}]},{"message":"Using generic Exception type in assertion is too broad. Consider asserting for a more specific exception type like ArgumentNullException or ArgumentException.","fixFiles":[{"filePath":"src/MandMCounter.Tests/SkittleTests.cs","diff":"diff --git a/src/MandMCounter.Tests/SkittleTests.cs b/src/MandMCounter.Tests/SkittleTests.cs\n--- a/src/MandMCounter.Tests/SkittleTests.cs\n+++ b/src/MandMCounter.Tests/SkittleTests.cs\n@@ -109,7 +109,7 @@\n             float quantity = 1;\n \n             //Act & Assert\n-            Assert.Throws<Exception>(() => Calculator.CountSkittles(unit, quantity));\n+            Assert.Throws<ArgumentNullException>(() => Calculator.CountSkittles(unit, quantity));\n         }\n \n         [TestMethod]\n"}]}]

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[github-actions]

Pull Request Test Coverage Report for Build 19936861958

Details

• 1 of 1 (100.0%) changed or added relevant line in 1 file are covered.
• 1 unchanged line in 1 file lost coverage.
• Overall coverage decreased (-10.4%) to 81.992%

---

Files with Coverage Reduction	New Missed Lines	%
src/MandMCounter.Core/Calculator.cs	1	80.17%

Totals
Change from base Build 19936563282:	-10.4%
Covered Lines:	100
Relevant Lines:	101

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💛 - Coveralls