Installing NuGet package with dependencies on multiple sources - visual-studio

Question

My job has a private NuGet repo. I'm able to install packages from it and from nuget.org. I'm running into problems when there's a package stored on the private repo that has a dependency on a package hosted on nuget.org.
For instance, my private repo hosts a package, P1. P1 has a dependency on P2 which is hosted on nuget.org. If do an "install-package P1" with my private repo set as the source i'll get an error saying it couldn't find the dependency P2. This makes sense since it's looking for P2 in the private repo but it's hosted on nuget.org. So far the workaround has been installing P2 from nuget.org then installing P1 from the private repo. While this technically works it's tedious and going to make selling NuGet to the rest of the team difficult.
Is there anyway I can run install-package with multiple sources? I've tried passing a list into the -Source parameter but so far have gotten
The NuGet.config is being managed by visual studio so any changes I make to it are being wiped out every time a run a nuget command in Visual Studio. I tried adding an additional nuget.config file at the solution level but as far as I can tell it was being ignored. I've tried several visitations of the install=package command but they generally look something like this:
Install-Package P1 -Source https://api.nuget.org/v3/index.json,http://privatefeed.com
For reference here is the NuGet.config file but changing it seems futile.
<?xml version="1.0" encoding="utf-8"?>
<configuration>
<packageRestore>
<add key="enabled" value="True" />
<add key="automatic" value="True" />
</packageRestore>
<packageSources>
<add key="nuget.org" value="https://api.nuget.org/v3/index.json" protocolVersion="3" />
<add key="Private Nuget" value="http://privatefeed.com" />
</packageSources>
<disabledPackageSources>
<add key="Microsoft and .NET" value="true" />
</disabledPackageSources>
<activePackageSource>
<add key="nuget.org" value="https://api.nuget.org/v3/index.json" />
</activePackageSource>
</configuration>

Answer 1

Using NuGet.exe, you can repeat the -Source option to specify multiple package sources.
Example:
nuget install P1 -Source https://api.nuget.org/v3/index.json -Source http://privatefeed.com
It appears that it's impossible to specify multiple sources using the Package Manage Console (PowerShell). However, if no -Source is specified then a NuGet.Config file is used. The config file can have multiple package sources and the file itself can be shared with a team.
<?xml version="1.0" encoding="utf-8"?>
<configuration>
<packageSources>
<add key="nuget.org" value="https://api.nuget.org/v3/index.json" protocolVersion="3" />
<add key="Private Nuget" value="http://privatefeed.com" />
</packageSources>
</configuration>
Save as NuGet.Config in the same directory as your solution and add it to version control.
Note that you might have to reload visual studio for the config changes to take effect.
Now you can install packages without configuring -Source.
Example:
Install-Package P1