[dotnet restore] --configfile is relative to project dir instead of the cmd dir

[phenixdotnet]

Initially reported at https://github.com/dotnet/cli/issues/2599

Steps to reproduce

Assume this solution structure:

• MySol
  • nuget.config
  • src
    • MyProject

Open a cmd prompt and move to MySol directory

Expected behavior

Relative path are evaluated from the current prompt directory and not from the project directory

Actual behavior

When running dotnet restore --configfile .\nuget.config from a cmd in MySol dir the command fail with this output:
error: File 'c:\dev\MySol\src\MyProject\.\nuget.config' does not exist.

Environment data

dotnet --info output:
.NET Command Line Tools (1.0.0-rc2-002439)

Product Information:
Version: 1.0.0-rc2-002439
Commit Sha: ef0c3b2cee

Runtime Environment:
OS Name: Windows
OS Version: 10.0.14316
OS Platform: Windows
RID: win10-x64

[emgarten]

It looks like the path is resolved against the project path because that is the root for settings. RestoreArgs should resolve the full path of the argument before passing it into settings.

https://github.com/NuGet/NuGet.Client/blob/dev/src/NuGet.Core/NuGet.Commands/RestoreCommand/RequestFactory/RestoreArgs.cs#L63