After the release of .NET Core 3.0, tests can no longer be run on evergreen. We see this error:
Unable to find source-code formatter for language: shell. Available languages are: actionscript, ada, applescript, bash, c, c#, c++, cpp, css, erlang, go, groovy, haskell, html, java, javascript, js, json, lua, none, nyan, objc, perl, php, python, r, rainbow, ruby, scala, sh, sql, swift, visualbasic, xml, yaml
2019/09/24 00:06:33.685] ======================================== [2019/09/24 00:06:33.685] Test [2019/09/24 00:06:34.380] ======================================== [2019/09/24 00:06:34.380] Executing task: Test [2019/09/24 00:06:34.380] Test run for C:\data\mci\606beaca569b4482f3673e9611661a5b\mongo-csharp-driver\tests\MongoDB.Bson.Tests\bin\Release\netcoreapp2.1\MongoDB.Bson.Tests.dll(.NETCoreApp,Version=v2.1) [2019/09/24 00:06:34.465] Microsoft (R) Test Execution Command Line Tool Version 16.3.0 [2019/09/24 00:06:34.543] Copyright (c) Microsoft Corporation. All rights reserved. [2019/09/24 00:06:34.588] Starting test execution, please wait... [2019/09/24 00:06:34.753] Testhost process exited with error: It was not possible to find any compatible framework version [2019/09/24 00:06:34.753] The specified framework 'Microsoft.NETCore.App', version '2.1.0' was not found. [2019/09/24 00:06:34.753] - The following frameworks were found: [2019/09/24 00:06:34.753] 3.0.0 at [C:\data\mci\606beaca569b4482f3673e9611661a5b\mongo-csharp-driver\.dotnet\shared\Microsoft.NETCore.App] [2019/09/24 00:06:34.753] 3.0.0 at [C:\Program Files\dotnet\shared\Microsoft.NETCore.App] [2019/09/24 00:06:34.753] You can resolve the problem by installing the specified framework and/or SDK. [2019/09/24 00:06:34.753] The .NET Core frameworks can be found at: [2019/09/24 00:06:34.753] - https://aka.ms/dotnet-download [2019/09/24 00:06:34.753] . Please check the diagnostic logs for more information
My initial hypothesis is that this is due to the way we're downloading the dotnet sdk: it's related to a previous build issue that resulted in us targeting netcoreapp2.1 instead of netcoreapp1.0