How can one have TFS source control ignore content files from packages?

[hugoqribeiro]

Hi.

We're having this tricky problem with a package that is used to share a common .editorconfig (named global.editorconfig).

That package (Primavera.Hydrogen.DesignTime.Configuration) adds .props file and the global.editorconfig like this:

<package xmlns="http://schemas.microsoft.com/packaging/2011/08/nuspec.xsd">
    <metadata>
        (...)
    </metadata>
    <files>
        <file src="Props\Primavera.Hydrogen.DesignTime.Configuration.Source.props" target="build\Primavera.Hydrogen.DesignTime.Configuration.props" />
        <file src="Files\global.editorconfig" target="build\global.editorconfig" />
        (...)
    </files>
</package>

The .props file itself configures the target project to use the global.editorconfig:

<Project>
    (...)
    <ItemGroup Condition="Exists('$(MSBuildThisFileDirectory)\global.editorconfig')" >
        <EditorConfigFiles Include="$(MSBuildThisFileDirectory)\global.editorconfig" />
    </ItemGroup>
</Project>

Now this where it gets tricky.

This package is added to the targets projects like this:

<Project Sdk="Microsoft.NET.Sdk">
  (...)
  <ItemGroup>
    <PackageReference Include="Primavera.Hydrogen.DesignTime.Configuration">
      <Version>4.0.*</Version>
      <PrivateAssets>all</PrivateAssets>
    </PackageReference>
  </ItemGroup>
  (...)
</Project>

The problem is that when we open a solution with this package and the package is restored the first time, TFS source control complains with the following message:

global.editorconfig

You are attempting to add an item to a source-controlled project, but the item's path has no mapping.  If you continue with the add, this item will not be added to source control.  Do you wish to proceed with the add?

NOTE:
The solution is here in on path D:\PrjNET\(...) and the packages are being restored to %UserProfile%\.nuget\packages.

Question

Anyone knows what can be done to have TFS ignore this kind of content files that are not actually in the project but instead are content files in design-time packages?