deps: update x/tools and gopls to db4c57db (#1021)

* gopls/internal/regtest: split regtests up into multiple packages db4c57db
* internal/lsp/cache: lock in snapshot.knownFilesInDir f871472f
* internal/lsp/source: make it an error to rename embedded fields c2bea79d
* gopls/internal/hooks: improve license file test 514964b7
* internal/lsp/cmd: improve help output of gopls subcommands 68bf78a6
* go/analysis/passes/fieldalignment: delete doc style comments in fix 4922717d
* gopls/internal/regtest: automate counting of editor notifications to await 917f61df
* internal/lsp: correct links provided in critical error pop-ups 2972602e
* internal/lsp: display current diagnostics in the debug server e13398c8
* gopls: factor out advanced documentation from the README cf1022a4
* gopls: mention workspaces and build systems in the README 87bc10f2
* internal/lsp: don't show context cancellation in the progress bar ce34e269
* gopls: merge README and user.md bec622c3
* gopls/internal/regtest: re-enable android builder 7e51fbd4

cmd/govim/internal/golang_org_x_tools/lsp/cache/load.go

@@ -203,8 +203,8 @@ func (s *snapshot) workspaceLayoutError(ctx context.Context) *source.CriticalErr
 	if !s.ValidBuildConfiguration() {
 		msg := `gopls requires a module at the root of your workspace.
 You can work with multiple modules by opening each one as a workspace folder.
-Improvements to this workflow will be coming soon (https://github.com/golang/go/issues/32394),
-and you can learn more here: https://github.com/golang/go/issues/36899.`
+Improvements to this workflow will be coming soon, and you can learn more here:
+https://github.com/golang/tools/blob/master/gopls/doc/workspace.md.`
 		return &source.CriticalError{
 			MainError: errors.Errorf(msg),
 			ErrorList: s.applyCriticalErrorToFiles(ctx, msg, openFiles),
@@ -236,13 +236,15 @@ and you can learn more here: https://github.com/golang/go/issues/36899.`
 			msg := fmt.Sprintf(`This file is in %s, which is a nested module in the %s module.
 gopls currently requires one module per workspace folder.
 Please open %s as a separate workspace folder.
-You can learn more here: https://github.com/golang/go/issues/36899.
+You can learn more here: https://github.com/golang/tools/blob/master/gopls/doc/workspace.md.
 `, modDir, filepath.Dir(rootModURI.Filename()), modDir)
 			srcErrs = append(srcErrs, s.applyCriticalErrorToFiles(ctx, msg, uris)...)
 		}
 		if len(srcErrs) != 0 {
 			return &source.CriticalError{
-				MainError: errors.Errorf(`You are working in a nested module. Please open it as a separate workspace folder.`),
+				MainError: errors.Errorf(`You are working in a nested module.
+Please open it as a separate workspace folder. Learn more:
+https://github.com/golang/tools/blob/master/gopls/doc/workspace.md.`),
 				ErrorList: srcErrs,
 			}
 		}

cmd/govim/internal/golang_org_x_tools/lsp/cache/snapshot.go

@@ -717,6 +717,9 @@ func (s *snapshot) allKnownSubdirs(ctx context.Context) map[span.URI]struct{} {
 // the given directory. It does not respect symlinks.
 func (s *snapshot) knownFilesInDir(ctx context.Context, dir span.URI) []span.URI {
 	var files []span.URI
+	s.mu.Lock()
+	defer s.mu.Unlock()
+
 	for uri := range s.files {
 		if source.InDir(dir.Filename(), uri.Filename()) {
 			files = append(files, uri)
@@ -1009,6 +1012,9 @@ func (s *snapshot) awaitLoaded(ctx context.Context) error {
 
 func (s *snapshot) GetCriticalError(ctx context.Context) *source.CriticalError {
 	loadErr := s.awaitLoadedAllErrors(ctx)
+	if errors.Is(loadErr, context.Canceled) {
+		return nil
+	}
 
 	// Even if packages didn't fail to load, we still may want to show
 	// additional warnings.
@@ -1075,6 +1081,10 @@ func (s *snapshot) awaitLoadedAllErrors(ctx context.Context) error {
 	// Do not return results until the snapshot's view has been initialized.
 	s.AwaitInitialized(ctx)
 
+	if ctx.Err() != nil {
+		return ctx.Err()
+	}
+
 	if err := s.reloadWorkspace(ctx); err != nil {
 		return err
 	}

cmd/govim/internal/golang_org_x_tools/lsp/cmd/call_hierarchy.go

@@ -30,8 +30,6 @@ Example:
   $ # 1-indexed location (:line:column or :#offset) of the target identifier
   $ gopls call_hierarchy helper/helper.go:8:6
   $ gopls call_hierarchy helper/helper.go:#53
-
-  gopls call_hierarchy flags are:
 `)
 	f.PrintDefaults()
 }

cmd/govim/internal/golang_org_x_tools/lsp/cmd/check.go

@@ -26,8 +26,6 @@ func (c *check) DetailedHelp(f *flag.FlagSet) {
 Example: show the diagnostic results of this file:
 
   $ gopls check internal/lsp/cmd/check.go
-
-	gopls check flags are:
 `)
 	f.PrintDefaults()
 }

cmd/govim/internal/golang_org_x_tools/lsp/cmd/highlight.go

@@ -30,8 +30,6 @@ Example:
   $ # 1-indexed location (:line:column or :#offset) of the target identifier
   $ gopls highlight helper/helper.go:8:6
   $ gopls highlight helper/helper.go:#53
-
-  gopls highlight flags are:
 `)
 	f.PrintDefaults()
 }

cmd/govim/internal/golang_org_x_tools/lsp/cmd/implementation.go

@@ -30,8 +30,6 @@ Example:
   $ # 1-indexed location (:line:column or :#offset) of the target identifier
   $ gopls implementation helper/helper.go:8:6
   $ gopls implementation helper/helper.go:#53
-
-  gopls implementation flags are:
 `)
 	f.PrintDefaults()
 }

cmd/govim/internal/golang_org_x_tools/lsp/cmd/prepare_rename.go

@@ -30,8 +30,6 @@ Example:
 	$ # 1-indexed location (:line:column or :#offset) of the target identifier
 	$ gopls prepare_rename helper/helper.go:8:6
 	$ gopls prepare_rename helper/helper.go:#53
-
-	gopls prepare_rename flags are:
 `)
 	f.PrintDefaults()
 }

cmd/govim/internal/golang_org_x_tools/lsp/cmd/semantictokens.go

@@ -67,8 +67,6 @@ func (c *semtok) DetailedHelp(f *flag.FlagSet) {
 Example: show the semantic tokens for this file:
 
   $ gopls semtok internal/lsp/cmd/semtok.go
-
-	gopls semtok flags are:
 `)
 	f.PrintDefaults()
 }

cmd/govim/internal/golang_org_x_tools/lsp/cmd/signature.go

@@ -29,8 +29,6 @@ Example:
   $ # 1-indexed location (:line:column or :#offset) of the target identifier
   $ gopls signature helper/helper.go:8:6
   $ gopls signature helper/helper.go:#53
-
-  gopls signature flags are:
 `)
 	f.PrintDefaults()
 }

cmd/govim/internal/golang_org_x_tools/lsp/debug/serve.go

@@ -181,6 +181,7 @@ type Client struct {
 	Logfile      string
 	GoplsPath    string
 	ServerID     string
+	Service      protocol.Server
 }
 
 // A Server is an outgoing connection to a remote LSP server.
@@ -314,6 +315,16 @@ func (i *Instance) getInfo(r *http.Request) interface{} {
 	return template.HTML(buf.String())
 }
 
+func (i *Instance) AddService(s protocol.Server, session *cache.Session) {
+	for _, c := range i.State.clients {
+		if c.Session == session {
+			c.Service = s
+			return
+		}
+	}
+	stdlog.Printf("unable to find a Client to add the protocol.Server to")
+}
+
 func getMemory(r *http.Request) interface{} {
 	var m runtime.MemStats
 	runtime.ReadMemStats(&m)
@@ -785,6 +796,29 @@ Using session: <b>{{template "sessionlink" .Session.ID}}</b><br>
 {{if .DebugAddress}}Debug this client at: <a href="http://{{localAddress .DebugAddress}}">{{localAddress .DebugAddress}}</a><br>{{end}}
 Logfile: {{.Logfile}}<br>
 Gopls Path: {{.GoplsPath}}<br>
+<h2>Diagnostics</h2>
+{{/*Service: []protocol.Server; each server has map[uri]fileReports;
+	each fileReport: map[diagnosticSoure]diagnosticReport
+	diagnosticSource is one of 5 source
+	diagnosticReport: snapshotID and map[hash]*source.Diagnostic
+	sourceDiagnostic: struct {
+		Range    protocol.Range
+		Message  string
+		Source   string
+		Code     string
+		CodeHref string
+		Severity protocol.DiagnosticSeverity
+		Tags     []protocol.DiagnosticTag
+
+		Related []RelatedInformation
+	}
+	RelatedInformation: struct {
+		URI     span.URI
+		Range   protocol.Range
+		Message string
+	}
+	*/}}
+<ul>{{range $k, $v := .Service.Diagnostics}}<li>{{$k}}:<ol>{{range $v}}<li>{{.}}</li>{{end}}</ol></li>{{end}}</ul>
 {{end}}
 `))
 

cmd/govim/internal/golang_org_x_tools/lsp/diagnostics.go

@@ -50,6 +50,23 @@ type fileReports struct {
 	reports       map[diagnosticSource]diagnosticReport
 }
 
+func (d diagnosticSource) String() string {
+	switch d {
+	case modSource:
+		return "FromSource"
+	case gcDetailsSource:
+		return "FromGCDetails"
+	case analysisSource:
+		return "FromAnalysis"
+	case typeCheckSource:
+		return "FromTypeChecking"
+	case orphanedSource:
+		return "FromOrphans"
+	default:
+		return fmt.Sprintf("From?%d?", d)
+	}
+}
+
 // hashDiagnostics computes a hash to identify diags.
 func hashDiagnostics(diags ...*source.Diagnostic) string {
 	source.SortDiagnostics(diags)
@@ -546,3 +563,34 @@ func (s *Server) shouldIgnoreError(ctx context.Context, snapshot source.Snapshot
 	})
 	return !hasGo
 }
+
+// Diagnostics formattedfor the debug server
+// (all the relevant fields of Server are private)
+// (The alternative is to export them)
+func (s *Server) Diagnostics() map[string][]string {
+	ans := make(map[string][]string)
+	s.diagnosticsMu.Lock()
+	defer s.diagnosticsMu.Unlock()
+	for k, v := range s.diagnostics {
+		fn := k.Filename()
+		for typ, d := range v.reports {
+			if len(d.diags) == 0 {
+				continue
+			}
+			for _, dx := range d.diags {
+				ans[fn] = append(ans[fn], auxStr(dx, d, typ))
+			}
+		}
+	}
+	return ans
+}
+
+func auxStr(v *source.Diagnostic, d diagnosticReport, typ diagnosticSource) string {
+	// Tags? RelatedInformation?
+	msg := fmt.Sprintf("(%s)%q(source:%q,code:%q,severity:%s,snapshot:%d,type:%s)",
+		v.Range, v.Message, v.Source, v.Code, v.Severity, d.snapshotID, typ)
+	for _, r := range v.Related {
+		msg += fmt.Sprintf(" [%s:%s,%q]", r.URI.Filename(), r.Range, r.Message)
+	}
+	return msg
+}

cmd/govim/internal/golang_org_x_tools/lsp/fake/editor.go

@@ -41,14 +41,17 @@ type Editor struct {
 	buffers map[string]buffer
 	// Capabilities / Options
 	serverCapabilities protocol.ServerCapabilities
+
 	// Call metrics for the purpose of expectations. This is done in an ad-hoc
 	// manner for now. Perhaps in the future we should do something more
-	// systematic.
-	calls CallCounts
+	// systematic. Guarded with a separate mutex as calls may need to be accessed
+	// asynchronously via callbacks into the Editor.
+	callsMu sync.Mutex
+	calls   CallCounts
 }
 
 type CallCounts struct {
-	DidOpen, DidChange, DidChangeWatchedFiles int
+	DidOpen, DidChange, DidSave, DidChangeWatchedFiles, DidClose uint64
 }
 
 type buffer struct {
@@ -140,8 +143,8 @@ func (e *Editor) Connect(ctx context.Context, conn jsonrpc2.Conn, hooks ClientHo
 }
 
 func (e *Editor) Stats() CallCounts {
-	e.mu.Lock()
-	defer e.mu.Unlock()
+	e.callsMu.Lock()
+	defer e.callsMu.Unlock()
 	return e.calls
 }
 
@@ -291,36 +294,48 @@ func (e *Editor) initialize(ctx context.Context, workspaceFolders []string) erro
 	return nil
 }
 
+// onFileChanges is registered to be called by the Workdir on any writes that
+// go through the Workdir API. It is called synchronously by the Workdir.
 func (e *Editor) onFileChanges(ctx context.Context, evts []FileEvent) {
 	if e.Server == nil {
 		return
 	}
-	e.mu.Lock()
-	defer e.mu.Unlock()
-	var lspevts []protocol.FileEvent
-	for _, evt := range evts {
-		// Always send an on-disk change, even for events that seem useless
-		// because they're shadowed by an open buffer.
-		lspevts = append(lspevts, evt.ProtocolEvent)
-
-		if buf, ok := e.buffers[evt.Path]; ok {
-			// Following VS Code, don't honor deletions or changes to dirty buffers.
-			if buf.dirty || evt.ProtocolEvent.Type == protocol.Deleted {
-				continue
-			}
 
-			content, err := e.sandbox.Workdir.ReadFile(evt.Path)
-			if err != nil {
-				continue // A race with some other operation.
+	// e may be locked when onFileChanges is called, but it is important that we
+	// synchronously increment this counter so that we can subsequently assert on
+	// the number of expected DidChangeWatchedFiles calls.
+	e.callsMu.Lock()
+	e.calls.DidChangeWatchedFiles++
+	e.callsMu.Unlock()
+
+	// Since e may be locked, we must run this mutation asynchronously.
+	go func() {
+		e.mu.Lock()
+		defer e.mu.Unlock()
+		var lspevts []protocol.FileEvent
+		for _, evt := range evts {
+			// Always send an on-disk change, even for events that seem useless
+			// because they're shadowed by an open buffer.
+			lspevts = append(lspevts, evt.ProtocolEvent)
+
+			if buf, ok := e.buffers[evt.Path]; ok {
+				// Following VS Code, don't honor deletions or changes to dirty buffers.
+				if buf.dirty || evt.ProtocolEvent.Type == protocol.Deleted {
+					continue
+				}
+
+				content, err := e.sandbox.Workdir.ReadFile(evt.Path)
+				if err != nil {
+					continue // A race with some other operation.
+				}
+				// During shutdown, this call will fail. Ignore the error.
+				_ = e.setBufferContentLocked(ctx, evt.Path, false, strings.Split(content, "\n"), nil)
 			}
-			// During shutdown, this call will fail. Ignore the error.
-			_ = e.setBufferContentLocked(ctx, evt.Path, false, strings.Split(content, "\n"), nil)
 		}
-	}
-	e.Server.DidChangeWatchedFiles(ctx, &protocol.DidChangeWatchedFilesParams{
-		Changes: lspevts,
-	})
-	e.calls.DidChangeWatchedFiles++
+		e.Server.DidChangeWatchedFiles(ctx, &protocol.DidChangeWatchedFilesParams{
+			Changes: lspevts,
+		})
+	}()
 }
 
 // OpenFile creates a buffer for the given workdir-relative file.
@@ -371,7 +386,9 @@ func (e *Editor) createBuffer(ctx context.Context, path string, dirty bool, cont
 		}); err != nil {
 			return errors.Errorf("DidOpen: %w", err)
 		}
+		e.callsMu.Lock()
 		e.calls.DidOpen++
+		e.callsMu.Unlock()
 	}
 	return nil
 }
@@ -393,6 +410,9 @@ func (e *Editor) CloseBuffer(ctx context.Context, path string) error {
 		}); err != nil {
 			return errors.Errorf("DidClose: %w", err)
 		}
+		e.callsMu.Lock()
+		e.calls.DidClose++
+		e.callsMu.Unlock()
 	}
 	return nil
 }
@@ -458,6 +478,9 @@ func (e *Editor) SaveBufferWithoutActions(ctx context.Context, path string) erro
 		if err := e.Server.DidSave(ctx, params); err != nil {
 			return errors.Errorf("DidSave: %w", err)
 		}
+		e.callsMu.Lock()
+		e.calls.DidSave++
+		e.callsMu.Unlock()
 	}
 	return nil
 }
@@ -653,7 +676,9 @@ func (e *Editor) setBufferContentLocked(ctx context.Context, path string, dirty
 		if err := e.Server.DidChange(ctx, params); err != nil {
 			return errors.Errorf("DidChange: %w", err)
 		}
+		e.callsMu.Lock()
 		e.calls.DidChange++
+		e.callsMu.Unlock()
 	}
 	return nil
 }

cmd/govim/internal/golang_org_x_tools/lsp/fake/workdir.go

@@ -211,7 +211,7 @@ func (w *Workdir) sendEvents(ctx context.Context, evts []FileEvent) {
 	copy(watchers, w.watchers)
 	w.watcherMu.Unlock()
 	for _, w := range watchers {
-		go w(ctx, evts)
+		w(ctx, evts)
 	}
 }
 

cmd/govim/internal/golang_org_x_tools/lsp/lsprpc/lsprpc.go

@@ -61,6 +61,7 @@ func (s *StreamServer) ServeStream(ctx context.Context, conn jsonrpc2.Conn) erro
 	server := s.serverForTest
 	if server == nil {
 		server = lsp.NewServer(session, client)
+		debug.GetInstance(ctx).AddService(server, session)
 	}
 	// Clients may or may not send a shutdown message. Make sure the server is
 	// shut down.