Adding 'TestCase' trait attribute (#13)

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src/Xunit.Categories/TestCaseAttribute.cs

@@ -0,0 +1,29 @@
+using System;
+using Xunit.Sdk;
+
+namespace Xunit.Categories
+{
+    /// <summary>
+    /// For annotating tests that relate to a specific Test Case
+    /// </summary>
+    [TraitDiscoverer(TestCaseDiscoverer.DiscovererTypeName, DiscovererUtil.AssemblyName)]
+    [AttributeUsage(AttributeTargets.Class | AttributeTargets.Method, AllowMultiple = true)]
+	public class TestCaseAttribute : Attribute, ITraitAttribute
+	{
+        public string TestCaseId { get; private set; }
+
+        public TestCaseAttribute(string testCaseId)
+		{
+			this.TestCaseId = testCaseId;
+		}
+
+		public TestCaseAttribute(long testCaseId)
+		{
+			this.TestCaseId = testCaseId.ToString();
+		}
+
+		public TestCaseAttribute()
+		{
+		}
+	}
+}

src/Xunit.Categories/TestCaseDiscoverer.cs

@@ -0,0 +1,28 @@
+using System.Collections.Generic;
+using Xunit.Abstractions;
+using Xunit.Sdk;
+
+namespace Xunit.Categories
+{
+    public class TestCaseDiscoverer : ITraitDiscoverer
+	{
+		internal const string DiscovererTypeName = DiscovererUtil.AssemblyName + "." + nameof(TestCaseDiscoverer);
+
+        /// <summary>
+        /// Gets the trait values from the trait attribute.
+        /// </summary>
+        /// <param name="traitAttribute"></param>
+        /// <returns></returns>
+		public IEnumerable<KeyValuePair<string, string>> GetTraits(IAttributeInfo traitAttribute)
+		{
+			var testCaseId = traitAttribute.GetNamedArgument<string>("TestCaseId");
+
+
+			yield return new KeyValuePair<string, string>("Category", "TestCase");
+
+			if (!string.IsNullOrWhiteSpace(testCaseId))
+				yield return new KeyValuePair<string, string>("TestCase", testCaseId);
+
+		}
+	}
+}

test/Xunit.Categories.Test/Scratch.cs

@@ -83,5 +83,14 @@ public void TestSystemTest()
         {
             throw new NotImplementedException("request #8 - This is more black box, high level, and stress testing of a complete running application different to an IntegrationTest");
         }
+
+        [Fact]
+        [WorkItem]
+        [WorkItem(999)]
+        [WorkItem("999")]
+        public void TestTestCase()
+        {
+            throw new NotImplementedException("I'm not that important, all the world knows about me, I'll be fixed in 2030");
+        }
     }
 }