问Team Foundation Server 2015 TestCategory不工作

EN

[TestMethod]        
[TestCategory("Dev")]
public void AllOrderItems() {
    //Assertions here.....
}

2016-05-17T18:11:07.5722452Z ##[debug]Entering script VSTest.ps1
2016-05-17T18:11:07.5732446Z ##[debug]vsTestVersion = 14.0
2016-05-17T18:11:07.5732446Z ##[debug]testAssembly = **\*tests*.dll;-:**\obj\**
2016-05-17T18:11:07.5742465Z ##[debug]testFiltercriteria = TestCategory=Dev
...
2016-05-17T18:11:08.1743177Z Executing C:\Program Files (x86)\Microsoft Visual Studio 14.0\Common7\IDE\CommonExtensions\Microsoft\TestWindow\vstest.console.exe "C:\TestAgentWork\35\s\APP.Business.Tests\bin\APP.Business.Tests.dll" "C:\TestAgentWork\35\s\APP.Business.Tests\bin\Test\APP.Business.Tests.dll" "C:\TestAgentWork\35\s\APP.Models.Tests\bin\Debug\APP.Models.Tests.dll" "C:\TestAgentWork\35\s\APP.Models.Tests\bin\APP.Models.Tests.dll" "C:\TestAgentWork\35\s\APP.Models.Tests\bin\Test\APP.Models.Tests.dll" "C:\TestAgentWork\35\s\APP.Web.Tests\bin\APP.Web.Tests.dll" "C:\TestAgentWork\35\s\APP.Web.Tests\bin\Test\APP.Web.Tests.dll"  /TestCaseFilter:"TestCategory=Dev" /logger:trx
...
2016-05-17T18:11:10.6976251Z ##[error]Error Message:
2016-05-17T18:11:10.6976251Z ##[error]   Assert.IsTrue failed. 
2016-05-17T18:11:10.6986243Z ##[error]Stack Trace:
2016-05-17T18:11:10.6996235Z ##[error]   at APP.Business.Tests.BusinessLayerTests.CheckIfCertifierSignatureOnFile() in C:\TestAgentWork\35\s\APP.Business.Tests\BusinessLayerTests.cs:line 516
2016-05-17T18:11:10.6996235Z Failed   CheckIfCertifierSignatureOnFile