Go to Definition fails over LSP for source generated files

[davidwengier]

Something is violating the expectations of the new Uri code:

Found while investigating #69732 and there is a link to a repro solution in there, but essentially execute a Go to Def via LSP to a source generated document.

/cc @tmat @jasonmalinowski

[dotnet-issue-labeler]

I couldn't figure out the best area label to add to this issue. If you have write-permissions please help me learn by adding exactly one area label.

[jasonmalinowski]

@davidwengier Nothing to do with the new URI code; this just isn't supported yet. The support is coming with #68771 and dotnet/vscode-csharp#5858.

[davidwengier]

Thanks, I was just about to comment that realisation, now that I've had time to think. I was so excited to get an exception investigating that competition issue, I just logged it right away :)

[davidwengier]

Feel free to close this as a dupe, though I have to ask - is that PR going to make things work in VS? Thats where I hit this, from a Razor file.

[jasonmalinowski]

Oh I thought that was VS Code. Uh, regular VS will require some different work, so let's keep this open then.

[dibarbet]

This still applies in VS - the editor cannot open the results provided by LSP - it throws with

StreamJsonRpc.RemoteInvocationException: There is no file system provider registered for the "source-generated" scheme.
Parameter name: remoteUri ---> System.ArgumentException: There is no file system provider registered for the "source-generated" scheme.
Parameter name: remoteUri
   at Microsoft.VisualStudio.PlatformUI.Packages.FileSystem.FileSystem.<InvokeRemoteFileSystemProviderAsync>d__66`1.MoveNext()

[jasonmalinowski]

@dibarbet Does VS give us a middleware concept where we can change the request before the LSP client processes it?

[dibarbet]

@jasonmalinowski I believe they do - what were you thinking of doing in it? Pointing to a different file on disk?

[jasonmalinowski]

If we can act as middleware for a go to definition (or other navigation operation) we can intercept the request and replace the source-generated URI with the one we generate in %TEMP%; from there when the shell opens it we'll then fill out the content as expected.

(Even better of course would be if the platform can natively support virtual documents!)