Restoring in-memory projects

[jjonescz]

NuGet Product Used

dotnet.exe

Product Version

.net 9

Worked before?

don't think so

Impact

It's more difficult to complete my work

Repro Steps & Context

MSBuild allows building projects in-memory. We want to use that for dotnet run file.cs effort, see dotnet/sdk#46915. However, some restore targets fail when they don't find the project file on disk.

We currently resort to hacks to avoid these targets failing. See https://github.com/dotnet/sdk/blob/fcd9a9224c91132226206ebd15922e42fb3ed483/src/Cli/dotnet/commands/VirtualProjectBuildingCommand.cs#L157-L179

It would be nice if NuGet targets handled in-memory builds gracefully.

Minimal example of in-memory build setup:

• Without the workaround (run that to see the failures): https://github.com/jjonescz/MSBuildInMemory/tree/d8c3f033faed37bd40e7024a2db20bca79545ed2
• With the workaround: https://github.com/jjonescz/MSBuildInMemory/tree/f32f90c88452868dc3dd124e54e23ce6eda67bb8