Add special character tests

src/ConfigCat.Client.Tests/BasicConfigCatClientIntegrationTests.cs

@@ -460,4 +460,31 @@ public void Ensure_Multiple_Requests_Doesnt_Interfere_In_ValueTasks()
             manualPollClient.ForceRefresh();
         });
     }
+
+    // https://app.configcat.com/v2/e7a75611-4256-49a5-9320-ce158755e3ba/08d5a03c-feb7-af1e-a1fa-40b3329f8bed/08dc016a-675e-4aa2-8492-6f572ad98037/244cf8b0-f604-11e8-b543-f23c917f9d8d
+    private const string SpecialCharactersSdkKey = "configcat-sdk-1/PKDVCLf-Hq-h-kCzMp-L7Q/u28_1qNyZ0Wz-ldYHIU7-g";
+
+    [TestMethod]
+    public async Task SpecialCharacters_Works_Cleartext()
+    {
+        using var client = ConfigCatClient.Get(SpecialCharactersSdkKey, options =>
+        {
+            options.PollingMode = PollingModes.LazyLoad();
+        });
+
+        var actual = await client.GetValueAsync("specialCharacters", "NOT_CAT", new User("äöüÄÖÜçéèñışğ⢙✓😀"));
+        Assert.AreEqual("äöüÄÖÜçéèñışğ⢙✓😀", actual);
+    }
+
+    [TestMethod]
+    public async Task SpecialCharacters_Works_Hashed()
+    {
+        using var client = ConfigCatClient.Get(SpecialCharactersSdkKey, options =>
+        {
+            options.PollingMode = PollingModes.LazyLoad();
+        });
+
+        var actual = await client.GetValueAsync("specialCharactersHashed", "NOT_CAT", new User("äöüÄÖÜçéèñışğ⢙✓😀"));
+        Assert.AreEqual("äöüÄÖÜçéèñışğ⢙✓😀", actual);
+    }
 }