Support NUnit TheoryAttribute

src/OmniSharp.DotNetTest/TestFrameworks/NUnitTestFramework.cs

@@ -10,7 +10,8 @@ protected override bool IsTestAttributeName(string typeName)
         {
             return typeName == "NUnit.Framework.TestAttribute"
                 || typeName == "NUnit.Framework.TestCaseAttribute"
-                || typeName == "NUnit.Framework.TestCaseSourceAttribute";
+                || typeName == "NUnit.Framework.TestCaseSourceAttribute"
+                || typeName == "NUnit.Framework.Theory";
         }
     }
 }

test-assets/test-projects/NUnitTestProject/TestProgram.cs

@@ -86,4 +86,17 @@ public void M()
 
         }
     }
+
+    [TestFixture(typeof(int))]
+    public class TheorySampleTestsGeneric<T>
+    {
+        [Datapoint]
+        public int[] ArrayInt = { 0, 1, 2, 3 };
+
+        [Theory]
+        public void TestGenericForArbitraryArray(T[] array)
+        {
+            Assert.That(array.Length, Is.EqualTo(4));
+        }
+    }
 }

tests/OmniSharp.DotNetTest.Tests/RunTestFacts.cs

@@ -222,6 +222,18 @@ public async Task RunNunitTypedTestRunsTwice()
             Assert.Equal(2, response.Results.Length);
         }
 
+        [Fact]
+        public async Task RunNunitTheoryTest()
+        {
+            var response = await RunDotNetTestAsync(
+                NUnitTestProject,
+                methodName: "Main.Test.TheorySampleTestsGeneric`1.TestGenericForArbitraryArray",
+                testFramework: "nunit",
+                shouldPass: true);
+
+            Assert.Single(response.Results);
+        }
+
         [Fact]
         public async Task RunMSTestTest()
         {