perf: replace redundant allocations with Linq (#4172)

Author: TimothyMakkison

TUnit.Engine/Discovery/ReflectionTestDataCollector.cs

@@ -503,7 +503,7 @@ private static async IAsyncEnumerable<TestMetadata> DiscoverTestsInAssemblyStrea
                 continue;
             }
 
-            MethodInfo[] testMethods;
+            IEnumerable<MethodInfo> testMethods;
             try
             {
                 // Check if this class inherits tests from base classes
@@ -513,15 +513,14 @@ private static async IAsyncEnumerable<TestMetadata> DiscoverTestsInAssemblyStrea
                 {
                     // Get all test methods including inherited ones
                     testMethods = GetAllTestMethods(type)
-                        .Where(static m => m.IsDefined(typeof(TestAttribute), inherit: false) && !m.IsAbstract)
-                        .ToArray();
+                        .Where(static m => m.IsDefined(typeof(TestAttribute), inherit: false) && !m.IsAbstract);
                 }
                 else
                 {
                     // Only get declared test methods
-                    testMethods = type.GetMethods(BindingFlags.Public | BindingFlags.Instance | BindingFlags.Static | BindingFlags.DeclaredOnly)
-                        .Where(static m => m.IsDefined(typeof(TestAttribute), inherit: false) && !m.IsAbstract)
-                        .ToArray();
+                    testMethods = type.GetMethods(BindingFlags.Public | BindingFlags.Instance | BindingFlags.Static |
+                                                  BindingFlags.DeclaredOnly)
+                        .Where(static m => m.IsDefined(typeof(TestAttribute), inherit: false) && !m.IsAbstract);
                 }
             }
             catch (Exception)

TUnit.Engine/Services/TestRegistry.cs

@@ -261,7 +261,9 @@ private async Task<TestMetadata> CreateMetadataFromDynamicDiscoveryResult(Dynami
             TestName = testName,
             TestClassType = result.TestClassType,
             TestMethodName = methodInfo.Name,
-            Dependencies = GetDependenciesOptimized(result.Attributes),
+            Dependencies = result.Attributes.OfType<DependsOnAttribute>()
+                .Select(x => x.ToTestDependency())
+                .ToArray(),
             DataSources = [],
             ClassDataSources = [],
             PropertyDataSources = [],
@@ -339,25 +341,6 @@ private sealed class PendingDynamicTest
         public required Type TestClassType { get; init; }
     }
 
-
-    /// <summary>
-    /// Optimized method to get dependencies without LINQ allocations
-    /// </summary>
-    private static TestDependency[] GetDependenciesOptimized(ICollection<Attribute> attributes)
-    {
-        var dependencies = new List<TestDependency>(attributes.Count);
-        foreach (var attr in attributes)
-        {
-            if (attr is DependsOnAttribute dependsOn)
-            {
-                dependencies.Add(dependsOn.ToTestDependency());
-            }
-        }
-        return dependencies.ToArray();
-    }
-
-
-
     /// <summary>
     /// Optimized method to convert attributes to array without LINQ allocations
     /// </summary>