Refactor Roslyn helpers and conversions (#282)

* Add CSharpLanguageServer.Roslyn.WorkspaceServices

* Extract solution functions to CSharpLanguageServer.Roslyn.Solution

* Extract CSharpLanguageServer.Roslyn.Symbol functions

* CSharpLanguageServer.Conversions: move CompletionContext.toCompletionTrigger inside CSharpLanguageServer.Handlers.Completion.handle

* Move CSharpLanguageServer.Conversions -> CSharpLanguageServer.Roslyn.Conversions ->

* Move CSharpLanguageServer.FormatUtil -> CSharpLanguageServer.Roslyn.Document

* CSharpLanguageServer.Handlers.Hover: rewrite in a more functional approach

* CSharpLanguageServer.Handlers.DocumentFormatting: rewrite in a more functional approach

* CSharpLanguageServer.Handlers.Implementation: rewrite in a more functional approach

* Apply fantomas

* Move documentFromMetadata to CSharpLanguageServer.Roslyn.Document

* src/CSharpLanguageServer/ProgressReporter.fs -> src/CSharpLanguageServer/Lsp/ProgressReporter.fs

Author: razzmatazz

src/CSharpLanguageServer/CSharpLanguageServer.fsproj

@@ -23,11 +23,13 @@
   <ItemGroup>
     <Compile Include="Logging.fs" />
     <Compile Include="Util.fs" />
-    <Compile Include="Conversions.fs" />
     <Compile Include="Types.fs" />
-    <Compile Include="FormatUtil.fs" />
-    <Compile Include="ProgressReporter.fs" />
-    <Compile Include="RoslynHelpers.fs" />
+    <Compile Include="Lsp/ProgressReporter.fs" />
+    <Compile Include="Roslyn/Conversions.fs" />
+    <Compile Include="Roslyn/WorkspaceServices.fs" />
+    <Compile Include="Roslyn/Solution.fs" />
+    <Compile Include="Roslyn/Document.fs" />
+    <Compile Include="Roslyn/Symbol.fs" />
     <Compile Include="DocumentationUtil.fs" />
     <Compile Include="Diagnostics.fs" />
     <Compile Include="Lsp/Client.fs" />

src/CSharpLanguageServer/Diagnostics.fs

@@ -8,7 +8,7 @@ open Ionide.LanguageServerProtocol.JsonRpc
 
 open CSharpLanguageServer.Types
 open CSharpLanguageServer.Logging
-open CSharpLanguageServer.RoslynHelpers
+open CSharpLanguageServer.Roslyn.Solution
 
 module Diagnostics =
     let private logger = Logging.getLoggerByName "Diagnostics"
@@ -58,13 +58,13 @@ module Diagnostics =
     let diagnose (settings: ServerSettings) : Async<int> = async {
         logger.LogDebug("diagnose: settings={settings}", settings)
 
-        initializeMSBuild logger
+        initializeMSBuild ()
 
         logger.LogDebug("diagnose: loading solution..")
 
         let lspClient = new LspClientStub()
         let cwd = string (Directory.GetCurrentDirectory())
-        let! _sln = loadSolutionOnSolutionPathOrDir lspClient logger None cwd
+        let! _sln = solutionLoadSolutionWithPathOrOnCwd lspClient None cwd
 
         logger.LogDebug("diagnose: done")
 

src/CSharpLanguageServer/DocumentationUtil.fs

@@ -5,7 +5,7 @@ open System.Xml.Linq
 
 open Microsoft.CodeAnalysis
 
-open CSharpLanguageServer.Conversions
+open CSharpLanguageServer.Roslyn.Conversions
 
 module DocumentationUtil =
     type TripleSlashComment =

src/CSharpLanguageServer/FormatUtil.fs

@@ -6,7 +6,7 @@ open Ionide.LanguageServerProtocol.Types
 open Ionide.LanguageServerProtocol.JsonRpc
 
 open CSharpLanguageServer.State
-open CSharpLanguageServer.Conversions
+open CSharpLanguageServer.Roslyn.Conversions
 
 [<RequireQualifiedAccess>]
 module CallHierarchy =

src/CSharpLanguageServer/Handlers/CallHierarchy.fs

@@ -18,7 +18,7 @@ open Ionide.LanguageServerProtocol.JsonRpc
 open Microsoft.Extensions.Logging
 
 open CSharpLanguageServer.Logging
-open CSharpLanguageServer.Conversions
+open CSharpLanguageServer.Roslyn.Conversions
 open CSharpLanguageServer.State
 open CSharpLanguageServer.Util
 

src/CSharpLanguageServer/Handlers/CodeAction.fs

@@ -9,7 +9,7 @@ open Ionide.LanguageServerProtocol.Types
 open Ionide.LanguageServerProtocol.JsonRpc
 
 open CSharpLanguageServer.State
-open CSharpLanguageServer.Conversions
+open CSharpLanguageServer.Roslyn.Conversions
 
 type private DocumentSymbolCollectorForCodeLens(semanticModel: SemanticModel) =
     inherit CSharpSyntaxWalker(SyntaxWalkerDepth.Token)

src/CSharpLanguageServer/Handlers/CodeLens.fs

@@ -10,7 +10,7 @@ open Ionide.LanguageServerProtocol.JsonRpc
 
 open CSharpLanguageServer.State
 open CSharpLanguageServer.Util
-open CSharpLanguageServer.Conversions
+open CSharpLanguageServer.Roslyn.Conversions
 open CSharpLanguageServer.Logging
 
 [<RequireQualifiedAccess>]
@@ -202,7 +202,19 @@ module Completion =
                     |> _.WithBool("ShowItemsFromUnimportedNamespaces", false)
                     |> _.WithBool("ShowNameSuggestions", false)
 
-                let completionTrigger = CompletionContext.toCompletionTrigger p.Context
+                let completionTrigger =
+                    p.Context
+                    |> Option.bind (fun ctx ->
+                        match ctx.TriggerKind with
+                        | CompletionTriggerKind.Invoked
+                        | CompletionTriggerKind.TriggerForIncompleteCompletions ->
+                            Some Microsoft.CodeAnalysis.Completion.CompletionTrigger.Invoke
+                        | CompletionTriggerKind.TriggerCharacter ->
+                            ctx.TriggerCharacter
+                            |> Option.map Seq.head
+                            |> Option.map Microsoft.CodeAnalysis.Completion.CompletionTrigger.CreateInsertionTrigger
+                        | _ -> None)
+                    |> Option.defaultValue Microsoft.CodeAnalysis.Completion.CompletionTrigger.Invoke
 
                 let shouldTriggerCompletion =
                     p.Context

src/CSharpLanguageServer/Handlers/Completion.fs

@@ -5,7 +5,7 @@ open Ionide.LanguageServerProtocol.Server
 open Ionide.LanguageServerProtocol.Types
 open Ionide.LanguageServerProtocol.JsonRpc
 
-open CSharpLanguageServer.Conversions
+open CSharpLanguageServer.Roslyn.Conversions
 open CSharpLanguageServer.State
 open CSharpLanguageServer.Types
 

src/CSharpLanguageServer/Handlers/Diagnostic.fs

@@ -4,21 +4,30 @@ open Microsoft.CodeAnalysis.Formatting
 open Ionide.LanguageServerProtocol.Types
 open Ionide.LanguageServerProtocol.JsonRpc
 
-open CSharpLanguageServer
 open CSharpLanguageServer.State
+open CSharpLanguageServer.Util
+open CSharpLanguageServer.Roslyn.Document
 
 [<RequireQualifiedAccess>]
+
 module DocumentFormatting =
-    let provider (clientCapabilities: ClientCapabilities) : U2<bool, DocumentFormattingOptions> option =
-        Some(U2.C1 true)
+    let provider (_cc: ClientCapabilities) : U2<bool, DocumentFormattingOptions> option = Some(U2.C1 true)
 
-    let handle (context: ServerRequestContext) (p: DocumentFormattingParams) : AsyncLspResult<TextEdit[] option> = async {
-        match context.GetUserDocument p.TextDocument.Uri with
-        | None -> return None |> LspResult.success
-        | Some doc ->
-            let! ct = Async.CancellationToken
-            let! options = FormatUtil.getFormattingOptions context.State.Settings doc p.Options
-            let! newDoc = Formatter.FormatAsync(doc, options, cancellationToken = ct) |> Async.AwaitTask
-            let! textEdits = FormatUtil.getChanges newDoc doc
-            return textEdits |> Some |> LspResult.success
+    let formatDocument lspFormattingOptions doc : Async<TextEdit array option> = async {
+        let! ct = Async.CancellationToken
+        let! options = getDocumentFormattingOptionSet doc lspFormattingOptions
+        let! newDoc = Formatter.FormatAsync(doc, options, cancellationToken = ct) |> Async.AwaitTask
+        let! textEdits = getDocumentDiffAsLspTextEdits newDoc doc
+        return textEdits |> Some
     }
+
+    let handle (context: ServerRequestContext) (p: DocumentFormattingParams) : AsyncLspResult<TextEdit[] option> =
+        let formatDocument =
+            p.Options
+            |> context.State.Settings.GetEffectiveFormattingOptions
+            |> formatDocument
+
+        context.GetUserDocument p.TextDocument.Uri
+        |> async.Return
+        |> Async.bindOption formatDocument
+        |> Async.map LspResult.success