feat: add option to require exact exception type in ExceptionParameterNameAssertion

TUnit.Assertions.Tests/Assertions/Delegates/Throws.WithParameterNameTests.cs

@@ -11,7 +11,7 @@ public async Task Fails_For_Different_Parameter_Name()
             var paramName1 = "foo";
             var paramName2 = "bar";
             var expectedMessage = """
-                                  Expected ArgumentException to have parameter name "bar"
+                                  Expected ArgumentException to have parameter name "bar" (exact type)
                                   but ArgumentException parameter name was "foo"
 
                                   at Assert.That(action).ThrowsExactly<ArgumentException>().WithParameterName("bar")

TUnit.Assertions/Conditions/ExceptionPropertyAssertions.cs

@@ -267,13 +267,16 @@ public class ExceptionParameterNameAssertion<TException> : Assertion<TException>
     where TException : Exception
 {
     private readonly string _expectedParameterName;
+    private readonly bool _requireExactType;
 
     public ExceptionParameterNameAssertion(
         AssertionContext<TException> context,
-        string expectedParameterName)
+        string expectedParameterName,
+        bool requireExactType = false)
         : base(context)
     {
         _expectedParameterName = expectedParameterName;
+        _requireExactType = requireExactType;
     }
 
     protected override Task<AssertionResult> CheckAsync(EvaluationMetadata<TException> metadata)
@@ -291,6 +294,13 @@ protected override Task<AssertionResult> CheckAsync(EvaluationMetadata<TExceptio
             return Task.FromResult(AssertionResult.Failed("no exception was thrown"));
         }
 
+        // If exact type is required, check that first
+        if (_requireExactType && exception.GetType() != typeof(TException))
+        {
+            return Task.FromResult(AssertionResult.Failed(
+                $"wrong exception type: {exception.GetType().Name} instead of exactly {typeof(TException).Name}"));
+        }
+
         if (exception is ArgumentException argumentException)
         {
             if (argumentException.ParamName == _expectedParameterName)
@@ -307,5 +317,7 @@ protected override Task<AssertionResult> CheckAsync(EvaluationMetadata<TExceptio
     }
 
     protected override string GetExpectation() =>
-        $"ArgumentException to have parameter name \"{_expectedParameterName}\"";
+        _requireExactType
+            ? $"{typeof(TException).Name} to have parameter name \"{_expectedParameterName}\" (exact type)"
+            : $"ArgumentException to have parameter name \"{_expectedParameterName}\"";
 }

TUnit.Assertions/Conditions/ThrowsAssertion.cs

@@ -339,7 +339,7 @@ public ExceptionMessageMatchesAssertion<TException> WithMessageMatching(StringMa
     public ExceptionParameterNameAssertion<TException> WithParameterName(string expectedParameterName)
     {
         Context.ExpressionBuilder.Append($".WithParameterName(\"{expectedParameterName}\")");
-        return new ExceptionParameterNameAssertion<TException>(Context, expectedParameterName);
+        return new ExceptionParameterNameAssertion<TException>(Context, expectedParameterName, requireExactType: true);
     }
 }
 

TUnit.PublicAPI/Tests.Assertions_Library_Has_No_API_Changes.DotNet10_0.verified.txt

@@ -669,7 +669,7 @@ namespace .Conditions
     public class ExceptionParameterNameAssertion<TException> : .<TException>
         where TException : 
     {
-        public ExceptionParameterNameAssertion(.<TException> context, string expectedParameterName) { }
+        public ExceptionParameterNameAssertion(.<TException> context, string expectedParameterName, bool requireExactType = false) { }
         protected override .<.> CheckAsync(.<TException> metadata) { }
         protected override string GetExpectation() { }
     }

TUnit.PublicAPI/Tests.Assertions_Library_Has_No_API_Changes.DotNet8_0.verified.txt

@@ -666,7 +666,7 @@ namespace .Conditions
     public class ExceptionParameterNameAssertion<TException> : .<TException>
         where TException : 
     {
-        public ExceptionParameterNameAssertion(.<TException> context, string expectedParameterName) { }
+        public ExceptionParameterNameAssertion(.<TException> context, string expectedParameterName, bool requireExactType = false) { }
         protected override .<.> CheckAsync(.<TException> metadata) { }
         protected override string GetExpectation() { }
     }

TUnit.PublicAPI/Tests.Assertions_Library_Has_No_API_Changes.DotNet9_0.verified.txt

@@ -669,7 +669,7 @@ namespace .Conditions
     public class ExceptionParameterNameAssertion<TException> : .<TException>
         where TException : 
     {
-        public ExceptionParameterNameAssertion(.<TException> context, string expectedParameterName) { }
+        public ExceptionParameterNameAssertion(.<TException> context, string expectedParameterName, bool requireExactType = false) { }
         protected override .<.> CheckAsync(.<TException> metadata) { }
         protected override string GetExpectation() { }
     }

TUnit.PublicAPI/Tests.Assertions_Library_Has_No_API_Changes.Net4_7.verified.txt

@@ -644,7 +644,7 @@ namespace .Conditions
     public class ExceptionParameterNameAssertion<TException> : .<TException>
         where TException : 
     {
-        public ExceptionParameterNameAssertion(.<TException> context, string expectedParameterName) { }
+        public ExceptionParameterNameAssertion(.<TException> context, string expectedParameterName, bool requireExactType = false) { }
         protected override .<.> CheckAsync(.<TException> metadata) { }
         protected override string GetExpectation() { }
     }