Is this a bug in Unity Test Framework 2.0.1 preivew ？

There are tesecases of both Editor mode and Play mode in my project.
Exception is thrown when switch to TestRunner widnow after finishing run all testcases in editor:

ArgumentException: An item with the same key has already been added. Key: TestAssetManagerLoadBundleAsync
UnityEditor.TestTools.TestRunner.GUI.TestListGUI.get_ResultsByKey () (at Packages/com.unity.test-framework/UnityEditor.TestRunner/GUI/Views/TestListGUIBase.cs:56)
UnityEditor.TestTools.TestRunner.GUI.TestListTreeViewDataSource.FetchData () (at Packages/com.unity.test-framework/UnityEditor.TestRunner/GUI/TestListTreeView/TestListTreeViewDataSource.cs:28)
UnityEditor.IMGUI.Controls.TreeViewDataSource.ReloadData () (at <c1da2d3b31364fe390649500fcb0efe5>:0)
UnityEditor.IMGUI.Controls.TreeViewController.ReloadData () (at <c1da2d3b31364fe390649500fcb0efe5>:0)
UnityEditor.TestTools.TestRunner.GUI.TestListGUI.Reload () (at Packages/com.unity.test-framework/UnityEditor.TestRunner/GUI/Views/TestListGUIBase.cs:301)
UnityEditor.TestTools.TestRunner.TestRunnerWindow.<StartRetrieveTestList>b__21_0 (UnityEditor.TestTools.TestRunner.Api.ITestAdaptor rootTest) (at Packages/com.unity.test-framework/UnityEditor.TestRunner/TestRunnerWindow.cs:128)
UnityEditor.TestTools.TestRunner.Api.TestRunnerApi+<>c__DisplayClass21_0.<RetrieveTestTree>b__1 (UnityEditor.TestTools.TestRunner.Api.ITestAdaptor testRoot) (at Packages/com.unity.test-framework/UnityEditor.TestRunner/Api/TestRunnerApi.cs:411)
UnityEditor.TestTools.TestRunner.TestListJob.EditorUpdate () (at Packages/com.unity.test-framework/UnityEditor.TestRunner/TestRunner/Utils/TestListJob.cs:32)
System.Reflection.MonoMethod.Invoke (System.Object obj, System.Reflection.BindingFlags invokeAttr, System.Reflection.Binder binder, System.Object[] parameters, System.Globalization.CultureInfo culture) (at <eae584ce26bc40229c1b1aa476bfa589>:0)
Rethrow as TargetInvocationException: Exception has been thrown by the target of an invocation.
System.Reflection.MonoMethod.Invoke (System.Object obj, System.Reflection.BindingFlags invokeAttr, System.Reflection.Binder binder, System.Object[] parameters, System.Globalization.CultureInfo culture) (at <eae584ce26bc40229c1b1aa476bfa589>:0)
System.Reflection.MethodBase.Invoke (System.Object obj, System.Object[] parameters) (at <eae584ce26bc40229c1b1aa476bfa589>:0)
System.Delegate.DynamicInvokeImpl (System.Object[] args) (at <eae584ce26bc40229c1b1aa476bfa589>:0)
System.MulticastDelegate.DynamicInvokeImpl (System.Object[] args) (at <eae584ce26bc40229c1b1aa476bfa589>:0)
System.Delegate.DynamicInvoke (System.Object[] args) (at <eae584ce26bc40229c1b1aa476bfa589>:0)
UnityEditor.EditorApplication.Internal_CallUpdateFunctions () (at <c1da2d3b31364fe390649500fcb0efe5>:0)

 

I figured out that by default if I run EditMode and PlayMode tests together, I'll get the same error on 2.*
If I deselect one of them or click on a subtree in the tests, then it works.

My test project only has 2 tests and they have different names, so that can't be the issue