Cohosting - Support LSP endpoints

[davidwengier]

Display

Endpoint	Cohosting	Calls Roslyn	Calls Web Tools	Notes
Diagnostics	✅ #10696 / #10882	Y: dotnet/roslyn#75102	Y	Roslyn dependencies are problematic
WorkspaceDiagnostics	✔️ N/A	N	N	Not supported by us
DocumentColor	✅ #10740	N	Y	Not in platform. See AB#2032948 Fixed with AB#570071
ColorPresentation	✅ #10740	N	Y	Not in platform. See AB#2032948 Fixed with AB#570071. Not supported in VS
DocumentSymbol	✅ #10689 / #10728	Y: dotnet/roslyn#74730	N
FoldingRange	✅#10447 / #10638	Y: dotnet/roslyn#73609	Y
InlayHints	✅ AB#567229 / #10672	Y: dotnet/roslyn#74548	N
ProjectContext	✔️ N/A	N	N	Roslyn handles this for us
SemanticTokensRange	✅ #10097 / #10619	Y: dotnet/roslyn#72495	N
SemanticTokensRefresh	✔️ N/A	N	N	Called from an interceptor now. Handled by Roslyn in cohosting
DocumentSpellCheck	✅ #10746 / #10825	Y: dotnet/roslyn#74978	N
WorkspaceSpellCheck	✔️ N/A	N	N	Not supported by us

Edit

Endpoint	Cohosting	Calls Roslyn	Calls Web Tools	Notes
OnAutoInsert	✅ #10630 / #10674	Y: dotnet/roslyn#73781	Y	No IBraceCompletionServices in OOP? Fixed in dotnet/roslyn#73756
CodeAction	🔜 #10742	Y	Y
Completion	🔜 #10697	Y	Y	Has dependency on CompletionListCache from LSP Services
TextPresentation	✅ #10740	Y	Y	Not supported in Roslyn
UriPresentation	✅ #10336 / #10642	Y	Y	Not supported in Roslyn
DocumentSync	✔️ N/A	N	N	Roslyn handles this for us
Formatting	✅ #10743 /#10822	N	Y	Calls Roslyn API
InlineCompletion	🔜 #10744	Y	N
LinkedEditingRange	✅ #10349 / #10596	N	N
MapCode	🔜 #10745	Y	N
Rename	✅ #10688 / #10721	Y: dotnet/roslyn#73781	Y
PrepareRename		dotnet/roslyn#73781	?	We don't suport this at the moment
WrapWithTag		N	Y	Not in platform
BreakpointSpan		N	N	Calls Roslyn API, but probably needs a re-think in a cohosted world
ProximityExpression		N	N	Calls Roslyn API, but probably needs a re-think in a cohosted world
ValidateBreakpointRange		Y	N

Navigate

Endpoint	Cohosting	Calls Roslyn	Calls Web Tools	Notes
CodeLens		Y	N	We don't support this at the moment. VS doesn't either.
Definition	✅ #10631 / #10750	Y: dotnet/roslyn#73781	Y	Needs MetadataAsFileService which needs Workspace Fixed in dotnet/roslyn#73781
DocumentHighlight	✅ #10656	Y	Y	Roslyn side isn't in OOP No idea why I wrote that.
FindAllReferences		Y	N	Roslyn side has WPF/problematic dependencies
Hover	🔜 #10839	Y	Y	Roslyn side has WPF dependencies
Implementation	✅ #10695 / #10824	Y: dotnet/roslyn#74978	Y
SignatureHelp	✅ #10595	Y: dotnet/roslyn#73781	Y	OOP service uses STJ (see: dotnet/roslyn#74280)

Other

Endpoint	Cohosting	Calls Roslyn	Calls Web Tools	Notes
RazorLanguageQuery		N	N	VS Code only. Hopefully unnecessary
RazorMapToDocumentRange		N	N	VS Code only. Hopefully unnecessary
MonitorConfigurationFilePath	✔️ N/A	N	N	Doesn't exist in Razor any more
ProjectInfo	✔️ N/A	N	N	Doesn't exist in Razor any more

[ryzngard]

❓are there any quick and easy ones for those not directly working on cohosting to fill a few hours and get used to the new design?

[davidwengier]

"Quick and easy" is a funny expression. I would say there is a heirachy of ease:

1. Razor only: Things that have "N" in both Roslyn and Web Tools columns, and therefore have no dependencies outside our repo. Sadly the only two of these left are outside of LSP, so might have other unknown hurdles.
2. Web Tools only: Things have an "N" in the Roslyn column, but "Y" in Web Tools, means all of the code changes are confined to our repo, since our method of communcation with Web Tools hasn't changed
3. "Easy" Roslyn: Things have a "Y*" in the Roslyn column, from a cursory look, use only workspace services in Roslyn, so should "just" be a matter of exposing helper methods through our EA, and calling them
4. Everything else: Things that have a "Y" in the Roslyn column potentially require rework or rearchitecting on the Roslyn side (modulo my understanding of MEF)

Worth noting that 3 and 4 are somewhat blocked on Roslyn LSP types being available to us, too