Consider Package Source Mapping sources for services in `NuGet.PackageManagement.VisualStudio`

[donnie-msft]

NuGet Product(s) Affected

Visual Studio Package Management UI

Current Behavior

PM UI uses feeds which directly query sources for package metadata.
This effectively bypasses Package Source Mapping since it considers all enabled sources.

Example,
https://github.com/NuGet/NuGet.Client/blob/84ba85d08b27afaa38ad4ae4e7e1684c74e9567c/src/NuGet.Clients/NuGet.PackageManagement.VisualStudio/PackageFeeds/MultiSourcePackageMetadataProvider.cs#L65

Desired Behavior

Consider Package Source Mapping sources for services in NuGet.PackageManagement.VisualStudio.
Ideally, extract the concept to an interface to help with testability across PM UI. Right now, PM UI and services have duplicated logic to call directly into source objects and ask for metadata, making it hard to test.

Additional Context

License Dialog in PM UI was addressed in NuGet/NuGet.Client#5295. While working on this, I discovered the other services which directly interact with package sources.

[jebriede]

Team triage: Tagging @nkolev92 who thinks there might be a duplicate issue.

[donnie-msft]

This is the only issue I've found, and it's not a dupe, but seems related: #12173

[nkolev92]

I can't find the dup. I think that got lost, but the general idea is great.

Things like "Updates" should only show updates from the source mapped sources.

[donnie-msft]

Customer filed a bug which effectively is an upvote for this DCR: #13983

[Aldebaran91]

This should be a higher priority as it also affects Azure DevOps builds. When I build an app, it might use the wrong feed to restore the nuget. The build would therefore fail.

[nkolev92]

This should be a higher priority as it also affects Azure DevOps builds. When I build an app, it might use the wrong feed to restore the nuget. The build would therefore fail.

Build should be completely unaffected by this gap.

Build runs restore which uses the package source mapping config as defined, there should be no issue there.
Are you getting NU1101 when restoring?

[Aldebaran91]

Build should be completely unaffected by this gap.

i think we are not on the same page. I am referring to my bug #13983 I reported. And if you still think this would be unaffected.
Why should updating a nuget be different from restoring a nuget? Again I am refferring to my bug #13983