add ConcurrentCacheTest

Author: xljiulang

WebApiClientTest/Internal/ConcurrentCacheTest.cs

@@ -0,0 +1,34 @@
+using System;
+using System.Collections.Generic;
+using System.Text;
+using WebApiClient;
+using Xunit;
+using System.Threading;
+using System.Threading.Tasks;
+
+namespace WebApiClientTest.Internal
+{
+    public class ConcurrentCacheTest
+    {
+        private int count = 0;
+
+        [Fact]
+        public void GetOrAddGet()
+        {
+            var key = "WebApiClient";
+            var cache = new ConcurrentCache<string, int>();
+
+            Parallel.For(0, 1000, (i) =>
+            {
+                var value = cache.GetOrAdd(key, k =>
+                {
+                    Interlocked.Increment(ref this.count);
+                    return 1;
+                });
+
+                Assert.True(value == 1);
+                Assert.True(count == 1);
+            });
+        }
+    }
+}