Fix Nunit1029 for generic test method (nunit#832)

cbersch · Jan 13, 2025 · c87166b · c87166b
1 parent f4a5549
commit c87166b
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Showing 2 changed files with 27 additions and 3 deletions.
diff --git a/src/nunit.analyzers.tests/TestCaseSourceUsage/TestCaseSourceUsesStringAnalyzerTests.cs b/src/nunit.analyzers.tests/TestCaseSourceUsage/TestCaseSourceUsesStringAnalyzerTests.cs
@@ -659,6 +659,30 @@ static IEnumerable<object> TestData()
             RoslynAssert.Valid(analyzer, testCode);
         }
 
+#if NUNIT4
+        [Test]
+        public void AnalyzeWhenNumberOfParametersOfGenericTestIsNotEvidentFromTestSource()
+        {
+            var testCode = TestUtility.WrapClassInNamespaceAndAddUsing(@"
+    [TestFixture]
+    public class AnalyzeWhenTestSourceProvidesDataWithSingleTypeArgs
+    {
+        [TestCaseSource(nameof(TestData))]
+        public void Method<T>()
+        {
+            Assert.That(typeof(T).IsValueType, Is.True);
+        }
+
+        static IEnumerable<TestCaseData> TestData()
+        {
+            yield return new TestCaseData { TypeArgs = new Type[] { typeof(int) } };
+        }
+    }", additionalUsings: "using System.Collections.Generic;");
+
+            RoslynAssert.Valid(analyzer, testCode);
+        }
+#endif
+
         [TestCase("IEnumerable", "object", "System.Collections")]
         [TestCase("IEnumerable<object>", "object", "System.Collections.Generic")]
         [TestCase("IEnumerable<TestCaseData>", "TestCaseData", "System.Collections.Generic")]

diff --git a/src/nunit.analyzers/TestCaseSourceUsage/TestCaseSourceUsesStringAnalyzer.cs b/src/nunit.analyzers/TestCaseSourceUsage/TestCaseSourceUsesStringAnalyzer.cs
@@ -248,16 +248,16 @@ private static void AnalyzeAttribute(
                             var hasCancelAfterAttribute = testMethod.GetAttributes().Any(a => SymbolEqualityComparer.Default.Equals(a.AttributeClass, cancelAfterType)) ||
                                 testMethod.ContainingType.GetAttributes().Any(a => SymbolEqualityComparer.Default.Equals(a.AttributeClass, cancelAfterType));
 
-                            var (methodRequiredParameters, methodOptionalParameters, methodParamsParameters) = testMethod.GetParameterCounts(hasCancelAfterAttribute, cancellationTokenType);
+                            var (methodRequiredParameters, methodOptionalParameters, _) = testMethod.GetParameterCounts(hasCancelAfterAttribute, cancellationTokenType);
 
                             if (elementType.SpecialType != SpecialType.System_String && (elementType.SpecialType == SpecialType.System_Object || elementType.IsIEnumerable(out _) ||
                                 IsOrDerivesFrom(elementType, context.SemanticModel.Compilation.GetTypeByMetadataName(NUnitFrameworkConstants.FullNameOfTypeTestCaseParameters))))
                             {
-                                // We only know that there is 1 or (likely) more parameters.
+                                // For non-generic methods we only know that there is 1 or (likely) more parameters, for generic methods we even don't know this for sure.
                                 // The object could hide an array, possibly with a variable number of elements: TestCaseData.Argument.
                                 // Potentially we could examine the body of the TestCaseSource to see if we can determine the exact amount.
                                 // For complex method that is certainly beyond the scope of this.
-                                if (methodRequiredParameters + methodOptionalParameters < 1)
+                                if (methodRequiredParameters + methodOptionalParameters < 1 && !testMethod.IsGenericMethod)
                                 {
                                     context.ReportDiagnostic(Diagnostic.Create(
                                             mismatchInNumberOfTestMethodParameters,