Add LanguageID configuration

Update #37

README.md

@@ -77,8 +77,19 @@ CodeActionsOnPut = ["source.organizeImports"]
 		hoverKind = "FullDocumentation"
 
 [[FilenameHandlers]]
-Pattern = '([/\\]go\.mod)|([/\\]go\.sum)|(\.go)$'
-ServerKey = "gopls"
+  Pattern = "[/\\\\]go\\.mod$"
+  LanguageID = "go.mod"
+  ServerKey = "gopls"
+
+[[FilenameHandlers]]
+  Pattern = "[/\\\\]go\\.sum$"
+  LanguageID = "go.sum"
+  ServerKey = "gopls"
+
+[[FilenameHandlers]]
+  Pattern = "\\.go$"
+  LanguageID = "go"
+  ServerKey = "gopls"
 ```
 
 ## Hints & Tips

internal/lsp/acmelsp/client.go

@@ -91,6 +91,7 @@ func (h *clientHandler) ApplyEdit(ctx context.Context, params *protocol.ApplyWor
 // ClientConfig contains LSP client configuration values.
 type ClientConfig struct {
 	*config.Server
+	*config.FilenameHandler
 	RootDirectory string                     // used to compute RootURI in initialization
 	HideDiag      bool                       // don't write diagnostics to DiagWriter
 	RPCTrace      bool                       // print LSP rpc trace to stderr
@@ -103,10 +104,11 @@ type ClientConfig struct {
 type Client struct {
 	protocol.Server
 	initializeResult *protocol.InitializeResult
+	cfg              *ClientConfig
 }
 
 func NewClient(conn net.Conn, cfg *ClientConfig) (*Client, error) {
-	c := &Client{}
+	c := &Client{cfg: cfg}
 	if err := c.init(conn, cfg); err != nil {
 		return nil, err
 	}

internal/lsp/acmelsp/client_test.go

@@ -78,7 +78,7 @@ func testGoModule(t *testing.T, server string, src string, f func(t *testing.T,
 	defer srv.Close()
 
 	ctx := context.Background()
-	err = lsp.DidOpen(ctx, srv.Client, gofile, []byte(src))
+	err = lsp.DidOpen(ctx, srv.Client, gofile, "go", []byte(src))
 	if err != nil {
 		t.Fatalf("DidOpen failed: %v", err)
 	}
@@ -306,7 +306,7 @@ func main() {
 	defer srv.Close()
 
 	ctx := context.Background()
-	err = lsp.DidOpen(ctx, srv.Client, gofile, []byte(src))
+	err = lsp.DidOpen(ctx, srv.Client, gofile, "go", []byte(src))
 	if err != nil {
 		t.Fatalf("DidOpen failed: %v", err)
 	}
@@ -375,7 +375,7 @@ func testPython(t *testing.T, src string, f func(t *testing.T, c *Client, uri pr
 	defer srv.Close()
 
 	ctx := context.Background()
-	err = lsp.DidOpen(ctx, srv.Client, pyfile, []byte(src))
+	err = lsp.DidOpen(ctx, srv.Client, pyfile, "python", []byte(src))
 	if err != nil {
 		t.Fatalf("DidOpen failed: %v", err)
 	}

internal/lsp/acmelsp/config/config.go

@@ -59,10 +59,6 @@ type File struct {
 	// LSP servers keyed by a user provided name.
 	Servers map[string]*Server
 
-	// LanguageHandlers is a mapping from LSP language ID to server key.
-	// This might be nice to support later, since this will avoid having to use regexp.
-	//LanguageHandlers map[string]string
-
 	// Servers determined by regular expression match on filename,
 	// as supplied by -server and -dial flags.
 	FilenameHandlers []FilenameHandler
@@ -107,6 +103,11 @@ type FilenameHandler struct {
 	// Pattern is a regular expression that matches filename.
 	Pattern string
 
+	// Language identifier (e.g. "go" or "python")
+	// See list of languages here:
+	// https://microsoft.github.io/language-server-protocol/specifications/specification-current/#textDocumentItem
+	LanguageID string
+
 	// ServerKey is the key in Config.File.Servers.
 	ServerKey string
 }

internal/lsp/acmelsp/exec.go

@@ -118,6 +118,7 @@ func dialServer(cs *config.Server, cfg *ClientConfig) (*Server, error) {
 // ServerInfo holds information about a LSP server and optionally a connection to it.
 type ServerInfo struct {
 	*config.Server
+	*config.FilenameHandler
 
 	Re     *regexp.Regexp // filename regular expression
 	Logger *log.Logger    // Logger for config.Server.LogFile
@@ -169,7 +170,7 @@ func NewServerSet(cfg *config.Config, diagWriter DiagnosticsWriter) (*ServerSet,
 	}
 
 	var data []*ServerInfo
-	for _, h := range cfg.FilenameHandlers {
+	for i, h := range cfg.FilenameHandlers {
 		cs, ok := cfg.Servers[h.ServerKey]
 		if !ok {
 			return nil, fmt.Errorf("server not found for key %q", h.ServerKey)
@@ -190,9 +191,10 @@ func NewServerSet(cfg *config.Config, diagWriter DiagnosticsWriter) (*ServerSet,
 			logger = log.New(f, "", log.LstdFlags)
 		}
 		data = append(data, &ServerInfo{
-			Server: cs,
-			Re:     re,
-			Logger: logger,
+			Server:          cs,
+			FilenameHandler: &cfg.FilenameHandlers[i],
+			Re:              re,
+			Logger:          logger,
 		})
 	}
 	return &ServerSet{
@@ -214,13 +216,14 @@ func (ss *ServerSet) MatchFile(filename string) *ServerInfo {
 
 func (ss *ServerSet) ClientConfig(info *ServerInfo) *ClientConfig {
 	return &ClientConfig{
-		Server:        info.Server,
-		RootDirectory: ss.cfg.RootDirectory,
-		HideDiag:      ss.cfg.HideDiagnostics,
-		RPCTrace:      ss.cfg.RPCTrace,
-		DiagWriter:    ss.diagWriter,
-		Workspaces:    ss.Workspaces(),
-		Logger:        info.Logger,
+		Server:          info.Server,
+		FilenameHandler: info.FilenameHandler,
+		RootDirectory:   ss.cfg.RootDirectory,
+		HideDiag:        ss.cfg.HideDiagnostics,
+		RPCTrace:        ss.cfg.RPCTrace,
+		DiagWriter:      ss.diagWriter,
+		Workspaces:      ss.Workspaces(),
+		Logger:          info.Logger,
 	}
 }
 

internal/lsp/acmelsp/files.go

@@ -126,7 +126,7 @@ func (fm *FileManager) didOpen(winid int, name string) error {
 		if err != nil {
 			return err
 		}
-		return lsp.DidOpen(context.Background(), c, name, b)
+		return lsp.DidOpen(context.Background(), c, name, c.cfg.FilenameHandler.LanguageID, b)
 	})
 }
 

internal/lsp/utils.go

@@ -70,11 +70,14 @@ func LocationLink(l *protocol.Location) string {
 		l.Range.End.Line+1, l.Range.End.Character+1)
 }
 
-func DidOpen(ctx context.Context, server protocol.Server, filename string, body []byte) error {
+func DidOpen(ctx context.Context, server protocol.Server, filename string, lang string, body []byte) error {
+	if lang == "" {
+		lang = DetectLanguage(filename)
+	}
 	return server.DidOpen(ctx, &protocol.DidOpenTextDocumentParams{
 		TextDocument: protocol.TextDocumentItem{
 			URI:        text.ToURI(filename),
-			LanguageID: DetectLanguage(filename),
+			LanguageID: lang,
 			Version:    0,
 			Text:       string(body),
 		},