internal/lsp: remove the Context argument from NewSession

The passed-in Context is not used, and creates the illusion of a startup
dependency problem: existing code is careful to pass in the context
containing the correct Client instance.

This allows passing in a source.Session, rather than a source.Cache,
into lsp server constructors.

Updates golang/go#34111

Change-Id: I081ad6fa800b846b63e04d7164577e3a32966704
Reviewed-on: https://go-review.googlesource.com/c/tools/+/215740
Run-TryBot: Robert Findley <rfindley@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Rebecca Stambler <rstambler@golang.org>
Reviewed-by: Ian Cottrell <iancottrell@google.com>

Author: findleyr

internal/lsp/cache/cache.go

@@ -73,7 +73,7 @@ func (c *cache) GetFile(uri span.URI) source.FileHandle {
 	}
 }
 
-func (c *cache) NewSession(ctx context.Context) source.Session {
+func (c *cache) NewSession() source.Session {
 	index := atomic.AddInt64(&sessionIndex, 1)
 	s := &session{
 		cache:    c,

internal/lsp/cmd/capabilities_test.go

@@ -40,7 +40,7 @@ func TestCapabilities(t *testing.T) {
 	params.Capabilities.Workspace.Configuration = true
 
 	// Send an initialize request to the server.
-	ctx, c.Server = lsp.NewClientServer(ctx, cache.New(app.options), c.Client)
+	ctx, c.Server = lsp.NewClientServer(ctx, cache.New(app.options).NewSession(), c.Client)
 	result, err := c.Server.Initialize(ctx, params)
 	if err != nil {
 		t.Fatal(err)

internal/lsp/cmd/cmd.go

@@ -192,7 +192,7 @@ func (app *Application) connect(ctx context.Context) (*connection, error) {
 	switch app.Remote {
 	case "":
 		connection := newConnection(app)
-		ctx, connection.Server = lsp.NewClientServer(ctx, cache.New(app.options), connection.Client)
+		ctx, connection.Server = lsp.NewClientServer(ctx, cache.New(app.options).NewSession(), connection.Client)
 		return connection, connection.initialize(ctx, app.options)
 	case "internal":
 		internalMu.Lock()
@@ -208,7 +208,7 @@ func (app *Application) connect(ctx context.Context) (*connection, error) {
 		ctx, jc, connection.Server = protocol.NewClient(ctx, jsonrpc2.NewHeaderStream(cr, cw), connection.Client)
 		go jc.Run(ctx)
 		go func() {
-			ctx, srv := lsp.NewServer(ctx, cache.New(app.options), jsonrpc2.NewHeaderStream(sr, sw))
+			ctx, srv := lsp.NewServer(ctx, cache.New(app.options).NewSession(), jsonrpc2.NewHeaderStream(sr, sw))
 			srv.Run(ctx)
 		}()
 		if err := connection.initialize(ctx, app.options); err != nil {

internal/lsp/cmd/serve.go

@@ -97,7 +97,7 @@ func (s *Serve) Run(ctx context.Context, args ...string) error {
 	if s.Trace {
 		stream = protocol.LoggingStream(stream, out)
 	}
-	ctx, srv := lsp.NewServer(ctx, cache.New(s.app.options), stream)
+	ctx, srv := lsp.NewServer(ctx, cache.New(s.app.options).NewSession(), stream)
 	return prepare(ctx, srv).Run(ctx)
 }
 

internal/lsp/cmd/test/cmdtest.go

@@ -140,6 +140,7 @@ func (r *runner) RunGoplsCmd(t testing.TB, args ...string) (string, string) {
 	return string(stdout), string(stderr)
 }
 
+// NormalizeGoplsCmd runs the gopls command and normalizes its output.
 func (r *runner) NormalizeGoplsCmd(t testing.TB, args ...string) (string, string) {
 	stdout, stderr := r.RunGoplsCmd(t, args...)
 	return r.Normalize(stdout), r.Normalize(stderr)

internal/lsp/lsp_test.go

@@ -52,7 +52,7 @@ func testLSP(t *testing.T, exporter packagestest.Exporter) {
 	defer data.Exported.Cleanup()
 
 	cache := cache.New(nil)
-	session := cache.NewSession(ctx)
+	session := cache.NewSession()
 	options := tests.DefaultOptions()
 	session.SetOptions(options)
 	options.Env = data.Config.Env
@@ -928,7 +928,7 @@ func TestModfileSuggestedFixes(t *testing.T) {
 
 	ctx := tests.Context(t)
 	cache := cache.New(nil)
-	session := cache.NewSession(ctx)
+	session := cache.NewSession()
 	options := tests.DefaultOptions()
 	options.TempModfile = true
 	options.Env = append(os.Environ(), "GOPACKAGESDRIVER=off", "GOROOT=")

internal/lsp/mod/mod_test.go

@@ -29,7 +29,7 @@ func TestMain(m *testing.M) {
 func TestModfileRemainsUnchanged(t *testing.T) {
 	ctx := tests.Context(t)
 	cache := cache.New(nil)
-	session := cache.NewSession(ctx)
+	session := cache.NewSession()
 	options := tests.DefaultOptions()
 	options.TempModfile = true
 	options.Env = append(os.Environ(), "GOPACKAGESDRIVER=off", "GOROOT=")
@@ -67,7 +67,7 @@ func TestModfileRemainsUnchanged(t *testing.T) {
 func TestDiagnostics(t *testing.T) {
 	ctx := tests.Context(t)
 	cache := cache.New(nil)
-	session := cache.NewSession(ctx)
+	session := cache.NewSession()
 	options := tests.DefaultOptions()
 	options.TempModfile = true
 	options.Env = append(os.Environ(), "GOPACKAGESDRIVER=off", "GOROOT=")

internal/lsp/server.go

@@ -18,23 +18,23 @@ import (
 )
 
 // NewClientServer
-func NewClientServer(ctx context.Context, cache source.Cache, client protocol.Client) (context.Context, *Server) {
+func NewClientServer(ctx context.Context, session source.Session, client protocol.Client) (context.Context, *Server) {
 	ctx = protocol.WithClient(ctx, client)
 	return ctx, &Server{
 		client:    client,
-		session:   cache.NewSession(ctx),
+		session:   session,
 		delivered: make(map[span.URI]sentDiagnostics),
 	}
 }
 
-// NewServer starts an LSP server on the supplied stream, and waits until the
-// stream is closed.
-func NewServer(ctx context.Context, cache source.Cache, stream jsonrpc2.Stream) (context.Context, *Server) {
+// NewServer creates an LSP server and binds it to handle incoming client
+// messages on on the supplied stream.
+func NewServer(ctx context.Context, session source.Session, stream jsonrpc2.Stream) (context.Context, *Server) {
 	s := &Server{
 		delivered: make(map[span.URI]sentDiagnostics),
+		session:   session,
 	}
 	ctx, s.Conn, s.client = protocol.NewServer(ctx, stream, s)
-	s.session = cache.NewSession(ctx)
 	return ctx, s
 }
 
@@ -56,7 +56,7 @@ func RunServerOnAddress(ctx context.Context, cache source.Cache, addr string, h
 		if err != nil {
 			return err
 		}
-		h(NewServer(ctx, cache, jsonrpc2.NewHeaderStream(conn, conn)))
+		h(NewServer(ctx, cache.NewSession(), jsonrpc2.NewHeaderStream(conn, conn)))
 	}
 }
 

internal/lsp/source/source_test.go

@@ -48,7 +48,7 @@ func testSource(t *testing.T, exporter packagestest.Exporter) {
 	defer data.Exported.Cleanup()
 
 	cache := cache.New(nil)
-	session := cache.NewSession(ctx)
+	session := cache.NewSession()
 	options := tests.DefaultOptions()
 	options.Env = data.Config.Env
 	view, _, err := session.NewView(ctx, "source_test", span.FileURI(data.Config.Dir), options)

internal/lsp/source/view.go

@@ -215,7 +215,7 @@ type Cache interface {
 	FileSystem
 
 	// NewSession creates a new Session manager and returns it.
-	NewSession(ctx context.Context) Session
+	NewSession() Session
 
 	// FileSet returns the shared fileset used by all files in the system.
 	FileSet() *token.FileSet