Server.fs: load solution-in-sync when initializing

This will help "server initializing" notification work better for
clients that depend on `initialize` request not to complete until the
server/solution is properly loaded initialized.

should fix #40 (lsp-mode loading spinner no longer working)

src/CSharpLanguageServer/RoslynHelpers.fs

@@ -1,11 +1,9 @@
 module CSharpLanguageServer.RoslynHelpers
 
 open System
-open System.Linq
 open System.Collections.Generic
 open System.IO
 open System.Reflection
-open System.Threading
 open Ionide.LanguageServerProtocol.Types
 open Microsoft.CodeAnalysis
 open Microsoft.CodeAnalysis.CodeActions
@@ -574,6 +572,17 @@ let findAndLoadSolutionOnDir logMessage dir = async {
         return solution
 }
 
+let loadSolutionOnSolutionPathOrCwd logMessage solutionPathMaybe =
+    match solutionPathMaybe with
+    | Some solutionPath ->
+        logMessage (sprintf "loading specified solution file: %s.." solutionPath)
+        tryLoadSolutionOnPath logMessage solutionPath
+
+    | None ->
+        let cwd = Directory.GetCurrentDirectory()
+        logMessage (sprintf "attempting to find and load solution based on cwd: \"%s\".." cwd)
+        findAndLoadSolutionOnDir logMessage cwd
+
 let getRoslynCodeActions (doc: Document) (textSpan: TextSpan): Async<CodeAction list> = async {
     let! ct = Async.CancellationToken
 

src/CSharpLanguageServer/Server.fs

@@ -214,7 +214,12 @@ let setupServerHandlers options (lspClient: LspClient) =
                     }
               }
 
-      initializeResult |> success |> async.Return
+      async {
+          // load solution (on stateActor)
+          do! stateActor.PostAndAsyncReply(SolutionReloadInSync)
+
+          return initializeResult |> success
+      }
 
     let handleInitialized (scope: ServerRequestScope) (_p: InitializedParams): Async<LspResult<unit>> =
         logMessage "\"initialized\" notification received from client"
@@ -238,11 +243,6 @@ let setupServerHandlers options (lspClient: LspClient) =
             | Ok _ -> ()
             | Error error -> infoMessage (sprintf "  ...didChangeWatchedFiles registration has failed with %s" (error |> string))
 
-            //
-            // start solution loading (on stateActor)
-            //
-            scope.Emit(SolutionReload)
-
             return LspResult.Ok()
         }
 

src/CSharpLanguageServer/State.fs

@@ -107,6 +107,7 @@ type ServerStateEvent =
     | ProcessRequestQueue
     | SolutionReloadRequest
     | SolutionReload
+    | SolutionReloadInSync of AsyncReplyChannel<unit>
     | PeriodicTimerTick
 
 let getDocumentForUriOfType state docType (u: string) =
@@ -224,20 +225,13 @@ let processServerEvent logMessage state postMsg msg: Async<ServerState> = async
         return { state with SolutionReloadPending = DateTime.Now.AddSeconds(5) |> Some }
 
     | SolutionReload ->
-        let! solution =
-            match state.Options.SolutionPath with
-            | Some solutionPath -> async {
-                logMessage (sprintf "loading specified solution file: %s.." solutionPath)
-                return! tryLoadSolutionOnPath logMessage solutionPath
-              }
-
-            | None -> async {
-                let cwd = Directory.GetCurrentDirectory()
-                logMessage (sprintf "attempting to find and load solution based on cwd: \"%s\".." cwd)
-                return! findAndLoadSolutionOnDir logMessage cwd
-              }
-
-        return { state with Solution = solution }
+        let! newSolution = loadSolutionOnSolutionPathOrCwd logMessage state.Options.SolutionPath
+        return { state with Solution = newSolution }
+
+    | SolutionReloadInSync replyChannel ->
+        let! newSolution = loadSolutionOnSolutionPathOrCwd logMessage state.Options.SolutionPath
+        replyChannel.Reply(())
+        return { state with Solution = newSolution }
 
     | PeriodicTimerTick ->
         let solutionReloadTime = state.SolutionReloadPending