[Bug]: nuget.exe install packages.config does not honor -PackageSaveMode nuspec

[huangqinjin]

NuGet Product Used

NuGet.exe

Product Version

5.10.0.7240

Worked before?

No response

Impact

It bothers me. A fix would be nice

Repro Steps & Context

packages.config:

<?xml version="1.0" encoding="utf-8"?>
<packages>
  <package id="Newtonsoft.Json" version="13.0.1" />
</packages>

1. nuget install packages.config -PackageSaveMode nuspec

What I expected:

Newtonsoft.Json.nuspec in folder Newtonsoft.Json.13.0.1.

What I got:

Newtonsoft.Json.13.0.1.nupkg in folder Newtonsoft.Json.13.0.1.

Verbose Logs

PS C:\Users\huangqinjin\Projects\test> nuget install packages.config -PackageSaveMode nuspec
Feeds used:
  C:\Users\huangqinjin\.nuget\packages\
  https://api.nuget.org/v3/index.json
  https://pkgs.dev.azure.com/dnceng/public/_packaging/dotnet-tools/nuget/v3/index.json
  C:\Program Files (x86)\Microsoft SDKs\NuGetPackages\
  C:\Users\huangqinjin\Projects\NuGet

Restoring NuGet package Newtonsoft.Json.13.0.1.
Adding package 'Newtonsoft.Json.13.0.1' to folder 'C:\Users\huangqinjin\Projects\test'
Added package 'Newtonsoft.Json.13.0.1' to folder 'C:\Users\huangqinjin\Projects\test'
PS C:\Users\huangqinjin\Projects\test> Get-ChildItem Newtonsoft.Json.13.0.1 -Name
lib
.signature.p7s
LICENSE.md
Newtonsoft.Json.13.0.1.nupkg
packageIcon.png
PS C:\Users\huangqinjin\Projects\test> Remove-Item -Recurse Newtonsoft.Json.13.0.1
PS C:\Users\huangqinjin\Projects\test> nuget install Newtonsoft.Json -Version 13.0.1 -PackageSaveMode nuspec
Feeds used:
  C:\Users\huangqinjin\.nuget\packages\
  https://api.nuget.org/v3/index.json
  https://pkgs.dev.azure.com/dnceng/public/_packaging/dotnet-tools/nuget/v3/index.json
  C:\Program Files (x86)\Microsoft SDKs\NuGetPackages\
  C:\Users\huangqinjin\Projects\NuGet



Attempting to gather dependency information for package 'Newtonsoft.Json.13.0.1' with respect to project 'C:\Users\huangqinjin\Projects\test', targeting 'Any,Version=v0.0'
Gathering dependency information took 2.32 sec
Attempting to resolve dependencies for package 'Newtonsoft.Json.13.0.1' with DependencyBehavior 'Lowest'
Resolving dependency information took 0 ms
Resolving actions to install package 'Newtonsoft.Json.13.0.1'
Resolved actions to install package 'Newtonsoft.Json.13.0.1'
Retrieving package 'Newtonsoft.Json 13.0.1' from 'C:\Users\huangqinjin\.nuget\packages\'.
Adding package 'Newtonsoft.Json.13.0.1' to folder 'C:\Users\huangqinjin\Projects\test'
Added package 'Newtonsoft.Json.13.0.1' to folder 'C:\Users\huangqinjin\Projects\test'
Successfully installed 'Newtonsoft.Json 13.0.1' to C:\Users\huangqinjin\Projects\test
Executing nuget actions took 329 ms
PS C:\Users\huangqinjin\Projects\test> Get-ChildItem Newtonsoft.Json.13.0.1 -Name
lib
.signature.p7s
LICENSE.md
Newtonsoft.Json.nuspec
packageIcon.png