Improve test assertions and exception types for null unit validation

[Copilot]

Apply code review feedback: use specific exception types and cleaner assertions in tests.

Test Improvements

SkittleTests.cs:

• Replace Assert.Throws<Exception> with Assert.Throws<ArgumentNullException> for null unit tests
• Remove empty lines after //Act comments

UnitsTests.cs:

• Rename UnitsTests → UnitTests (standard naming)
• Assert.IsTrue(results != null) → Assert.IsNotNull(results)
• Assert.IsTrue(string.IsNullOrEmpty(x) == false) → Assert.IsFalse(string.IsNullOrEmpty(x))

Core Code Fix

Updated GetCubicCmForRectangle and GetCubicCmForCylinder to throw ArgumentNullException on null/empty unit, matching existing pattern in GetCubicCmForVolume:

// Before: silent empty string assignment, falls through to generic Exception
if (string.IsNullOrEmpty(unit))
    unit = "";

// After: explicit ArgumentNullException
if (string.IsNullOrEmpty(unit))
    throw new ArgumentNullException(nameof(unit), "Unit cannot be null or empty.");

Note: CollectionAssert.IsNotEmpty from diff was skipped—not available in MSTest.

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":"Catching the generic Exception type is too broad. Consider asserting for a more specific exception type like ArgumentNullException to match the pattern used in line 112.","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@@ -178,7 +178,7 @@\n             //Act\n \n             //Assert\n-            Assert.Throws<Exception>(() => Calculator.CountSkittles(unit, height, width, length));\n+            Assert.Throws<ArgumentNullException>(() => Calculator.CountSkittles(unit, height, width, length));\n         }\n \n         #endregion\n"}]},{"message":"Catching the generic Exception type is too broad. Consider asserting for a more specific exception type like ArgumentNullException to match the pattern used in line 112.","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@@ -226,7 +226,7 @@\n             float radius = 5;\n \n             //Act & Assert\n-            Assert.Throws<Exception>(() => Calculator.CountSkittles(unit, height, radius));\n+            Assert.Throws<ArgumentNullException>(() => Calculator.CountSkittles(unit, height, radius));\n         }\n \n         #endregion\n"}]},{"message":"[nitpick] Empty line after //Act comment is unnecessary and appears consistently throughout the test file, creating visual clutter.","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@@ -18,7 +18,6 @@\n             float quantity = 1f;\n \n             //Act\n-            \n             float result = Calculator.CountSkittles(unit, quantity);\n \n             //Assert\n@@ -33,7 +32,6 @@\n             float quantity = 1f;\n \n             //Act\n-            \n             float result = Calculator.CountSkittles(unit, quantity);\n \n             //Assert\n@@ -48,7 +46,6 @@\n             float quantity = 1f;\n \n             //Act\n-            \n             float result = Calculator.CountSkittles(unit, quantity);\n \n             //Assert\n"}]},{"message":"The class name 'UnitsTests' should be 'UnitTests' to follow standard naming conventions for test classes.","fixFiles":[{"filePath":"src/MandMCounter.Tests/UnitsTests.cs","diff":"diff --git a/src/MandMCounter.Tests/UnitsTests.cs b/src/MandMCounter.Tests/UnitsTests.cs\n--- a/src/MandMCounter.Tests/UnitsTests.cs\n+++ b/src/MandMCounter.Tests/UnitsTests.cs\n@@ -7,7 +7,7 @@\n {\n     [System.Diagnostics.CodeAnalysis.ExcludeFromCodeCoverage]\n     [TestClass]\n-    public class UnitsTests\n+    public class UnitTests\n     {\n         [TestMethod]\n         public void GetUnitsForVolumeTest()\n"}]},{"message":"Use Assert.IsNotNull(results) instead of Assert.IsTrue(results != null) for clearer intent and better error messages.","fixFiles":[{"filePath":"src/MandMCounter.Tests/UnitsTests.cs","diff":"diff --git a/src/MandMCounter.Tests/UnitsTests.cs b/src/MandMCounter.Tests/UnitsTests.cs\n--- a/src/MandMCounter.Tests/UnitsTests.cs\n+++ b/src/MandMCounter.Tests/UnitsTests.cs\n@@ -18,7 +18,7 @@\n             List<string> results = Units.GetUnitsForVolume();\n \n             //Assert\n-            Assert.IsTrue(results != null);\n+            Assert.IsNotNull(results);\n             Assert.IsTrue(results.Count > 0);\n             Assert.IsTrue(string.IsNullOrEmpty(results[0]) == false);\n         }\n@@ -32,7 +32,7 @@\n             List<string> results = Units.GetUnitsForContainer();\n \n             //Assert\n-            Assert.IsTrue(results != null);\n+            Assert.IsNotNull(results);\n             Assert.IsTrue(results.Count > 0);\n             Assert.IsTrue(string.IsNullOrEmpty(results[0]) == false);\n         }\n"}]},{"message":"[nitpick] Consider using CollectionAssert.IsNotEmpty(results) or Assert.IsTrue(results.Any()) for more descriptive collection assertions.","fixFiles":[{"filePath":"src/MandMCounter.Tests/UnitsTests.cs","diff":"diff --git a/src/MandMCounter.Tests/UnitsTests.cs b/src/MandMCounter.Tests/UnitsTests.cs\n--- a/src/MandMCounter.Tests/UnitsTests.cs\n+++ b/src/MandMCounter.Tests/UnitsTests.cs\n@@ -19,7 +19,7 @@\n \n             //Assert\n             Assert.IsTrue(results != null);\n-            Assert.IsTrue(results.Count > 0);\n+            CollectionAssert.IsNotEmpty(results);\n             Assert.IsTrue(string.IsNullOrEmpty(results[0]) == false);\n       ...

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[github-actions]

Pull Request Test Coverage Report for Build 19940932922

Details

• 2 of 2 (100.0%) changed or added relevant lines in 1 file are covered.
• 2 unchanged lines in 1 file lost coverage.
• Overall coverage decreased (-10.2%) to 71.815%

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Files with Coverage Reduction	New Missed Lines	%
src/MandMCounter.Core/Calculator.cs	2	68.94%

Totals
Change from base Build 19940648005:	-10.2%
Covered Lines:	96
Relevant Lines:	99

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💛 - Coveralls