fix: enhance enum exclusion handling in MatrixDataSourceAttribute and add related tests (#3322)

Author: thomhurst

TUnit.Core/Attributes/TestData/MatrixDataSourceAttribute.cs

@@ -66,12 +66,17 @@ private bool IsExcluded(object?[] exclusion, IEnumerable<object?> row)
             var exclusionValue = exclusion[i];
             var rowValue = rowArray[i];
 
-            // Handle enum to underlying type conversion
-            if (exclusionValue != null && exclusionValue.GetType().IsEnum && rowValue != null)
+            // Handle enum to underlying type conversion for both values
+            if (exclusionValue != null && exclusionValue.GetType().IsEnum)
             {
                 exclusionValue = Convert.ChangeType(exclusionValue, Enum.GetUnderlyingType(exclusionValue.GetType()));
             }
 
+            if (rowValue != null && rowValue.GetType().IsEnum)
+            {
+                rowValue = Convert.ChangeType(rowValue, Enum.GetUnderlyingType(rowValue.GetType()));
+            }
+
             if (!Equals(exclusionValue, rowValue))
             {
                 return false;

TUnit.TestProject/MatrixExclusionBugTest.cs

@@ -32,18 +32,65 @@ public async Task Should_Filter_By_Status(Status status)
         }
         await Task.CompletedTask;
     }
-    
+
     [Test]
     [MatrixDataSource]
     [MatrixExclusion(Status.Draft)]  // This should work with the base attribute
     public async Task Should_Filter_By_Status_Base(Status status)
     {
         // Should generate 4 tests (all statuses except Draft)
-        // If this test runs with Status.Draft, the bug is NOT fixed  
+        // If this test runs with Status.Draft, the bug is NOT fixed
         if (status == Status.Draft)
         {
             throw new InvalidOperationException("Draft status should have been excluded but was not!");
         }
         await Task.CompletedTask;
     }
+
+    // Issue #3320: Test Matrix attribute with explicit enum values + MatrixExclusion
+    [Test]
+    [MatrixDataSource]
+    [MatrixExclusion(Status.Draft)]
+    public async Task Matrix_With_Explicit_Enums_Should_Respect_Exclusion(
+        [Matrix(Status.Draft, Status.Pending, Status.Published)] Status status)
+    {
+        // Should generate 2 tests (Pending and Published only, Draft is excluded)
+        await Assert.That(status).IsNotEqualTo(Status.Draft);
+    }
+
+    // Issue #3320: Test with multiple enum parameters and exclusion
+    [Test]
+    [MatrixDataSource]
+    [MatrixExclusion(Status.Draft, Status.Pending)]
+    public async Task Multiple_Enum_Matrix_With_Exclusion(
+        [Matrix(Status.Draft, Status.Published)] Status status1,
+        [Matrix(Status.Pending, Status.Archived)] Status status2)
+    {
+        // Should exclude (Draft, Pending) combination
+        // Should generate 3 tests: (Draft,Archived), (Published,Pending), (Published,Archived)
+        await Assert.That((status1, status2)).IsNotEqualTo((Status.Draft, Status.Pending));
+    }
+
+    // Issue #3320: Test with int cast exclusion (this was already working)
+    [Test]
+    [MatrixDataSource]
+    [MatrixExclusion((int)Status.Draft)]
+    public async Task Matrix_Enum_With_Int_Exclusion(
+        [Matrix(Status.Draft, Status.Pending, Status.Published)] Status status)
+    {
+        // Should generate 2 tests (Pending and Published only)
+        await Assert.That(status).IsNotEqualTo(Status.Draft);
+    }
+
+    // Issue #3320: Test mixing auto-generated and explicit Matrix enums
+    [Test]
+    [MatrixDataSource]
+    [MatrixExclusion(Status.Draft, Status.Pending)]
+    public async Task Mixed_Auto_And_Explicit_Matrix_Enums(
+        Status autoGenerated,
+        [Matrix(Status.Pending, Status.Published)] Status explicitMatrix)
+    {
+        // Should exclude (Draft, Pending) combination
+        await Assert.That((autoGenerated, explicitMatrix)).IsNotEqualTo((Status.Draft, Status.Pending));
+    }
 }