internal/lsp: stop making background contexts everywhere

For all uses inside the lsp we use the detatch logic instead
For tests we build it in the test harness instead
This is in preparation for things on the context becomming important

Change-Id: I7e6910e0d3581b82abbeeb09f9c22a99efb73142
Reviewed-on: https://go-review.googlesource.com/c/tools/+/185677
Run-TryBot: Ian Cottrell <iancottrell@google.com>
Reviewed-by: Rebecca Stambler <rstambler@golang.org>

Author: ianthehat

internal/lsp/cache/session.go

@@ -18,6 +18,7 @@ import (
 	"golang.org/x/tools/internal/lsp/source"
 	"golang.org/x/tools/internal/lsp/xlog"
 	"golang.org/x/tools/internal/span"
+	"golang.org/x/tools/internal/xcontext"
 )
 
 type session struct {
@@ -64,11 +65,11 @@ func (s *session) Cache() source.Cache {
 	return s.cache
 }
 
-func (s *session) NewView(name string, folder span.URI) source.View {
+func (s *session) NewView(ctx context.Context, name string, folder span.URI) source.View {
 	index := atomic.AddInt64(&viewIndex, 1)
 	s.viewMu.Lock()
 	defer s.viewMu.Unlock()
-	ctx := context.Background()
+	ctx = xcontext.Detach(ctx)
 	backgroundCtx, cancel := context.WithCancel(ctx)
 	v := &view{
 		session:       s,

internal/lsp/cmd/check_test.go

@@ -5,7 +5,6 @@
 package cmd_test
 
 import (
-	"context"
 	"fmt"
 	"strings"
 	"testing"
@@ -23,7 +22,7 @@ func (r *runner) Diagnostics(t *testing.T, data tests.Diagnostics) {
 		fname := uri.Filename()
 		args := []string{"-remote=internal", "check", fname}
 		out := captureStdOut(t, func() {
-			tool.Main(context.Background(), r.app, args)
+			tool.Main(r.ctx, r.app, args)
 		})
 		// parse got into a collection of reports
 		got := map[string]struct{}{}

internal/lsp/cmd/cmd.go

@@ -26,6 +26,7 @@ import (
 	"golang.org/x/tools/internal/lsp/source"
 	"golang.org/x/tools/internal/span"
 	"golang.org/x/tools/internal/tool"
+	"golang.org/x/tools/internal/xcontext"
 )
 
 // Application is the main application as passed to tool.Main
@@ -148,7 +149,7 @@ func (app *Application) connect(ctx context.Context) (*connection, error) {
 			return c, nil
 		}
 		connection := newConnection(app)
-		ctx := context.Background() //TODO:a way of shutting down the internal server
+		ctx := xcontext.Detach(ctx) //TODO:a way of shutting down the internal server
 		cr, sw, _ := os.Pipe()
 		sr, cw, _ := os.Pipe()
 		var jc *jsonrpc2.Conn

internal/lsp/cmd/cmd_test.go

@@ -6,6 +6,7 @@ package cmd_test
 
 import (
 	"bytes"
+	"context"
 	"io/ioutil"
 	"os"
 	"path/filepath"
@@ -24,6 +25,7 @@ type runner struct {
 	exporter packagestest.Exporter
 	data     *tests.Data
 	app      *cmd.Application
+	ctx      context.Context
 }
 
 func TestCommandLine(t *testing.T) {
@@ -38,6 +40,7 @@ func testCommandLine(t *testing.T, exporter packagestest.Exporter) {
 		exporter: exporter,
 		data:     data,
 		app:      cmd.New(data.Config.Dir, data.Exported.Config.Env),
+		ctx:      tests.Context(t),
 	}
 	tests.Run(t, r, data)
 }

internal/lsp/cmd/definition_test.go

@@ -5,7 +5,6 @@
 package cmd_test
 
 import (
-	"context"
 	"fmt"
 	"os"
 	"path/filepath"
@@ -56,7 +55,7 @@ func TestDefinitionHelpExample(t *testing.T) {
 		fmt.Sprintf("%v:#%v", thisFile, cmd.ExampleOffset)} {
 		args := append(baseArgs, query)
 		got := captureStdOut(t, func() {
-			tool.Main(context.Background(), cmd.New("", nil), args)
+			tool.Main(tests.Context(t), cmd.New("", nil), args)
 		})
 		if !expect.MatchString(got) {
 			t.Errorf("test with %v\nexpected:\n%s\ngot:\n%s", args, expect, got)
@@ -84,7 +83,7 @@ func (r *runner) Definition(t *testing.T, data tests.Definitions) {
 			uri := d.Src.URI()
 			args = append(args, fmt.Sprint(d.Src))
 			got := captureStdOut(t, func() {
-				tool.Main(context.Background(), r.app, args)
+				tool.Main(r.ctx, r.app, args)
 			})
 			got = normalizePaths(r.data, got)
 			if mode&jsonGoDef != 0 && runtime.GOOS == "windows" {

internal/lsp/cmd/format_test.go

@@ -5,7 +5,6 @@
 package cmd_test
 
 import (
-	"context"
 	"os/exec"
 	"regexp"
 	"strings"
@@ -40,7 +39,7 @@ func (r *runner) Format(t *testing.T, data tests.Formats) {
 			}
 			app := cmd.New(r.data.Config.Dir, r.data.Config.Env)
 			got := captureStdOut(t, func() {
-				tool.Main(context.Background(), app, append([]string{"-remote=internal", "format"}, args...))
+				tool.Main(r.ctx, app, append([]string{"-remote=internal", "format"}, args...))
 			})
 			got = normalizePaths(r.data, got)
 			// check the first two lines are the expected file header

internal/lsp/lsp_test.go

@@ -32,18 +32,20 @@ func TestLSP(t *testing.T) {
 type runner struct {
 	server *Server
 	data   *tests.Data
+	ctx    context.Context
 }
 
 const viewName = "lsp_test"
 
 func testLSP(t *testing.T, exporter packagestest.Exporter) {
+	ctx := tests.Context(t)
 	data := tests.Load(t, exporter, "testdata")
 	defer data.Exported.Cleanup()
 
 	log := xlog.New(xlog.StdSink{})
 	cache := cache.New()
 	session := cache.NewSession(log)
-	view := session.NewView(viewName, span.FileURI(data.Config.Dir))
+	view := session.NewView(ctx, viewName, span.FileURI(data.Config.Dir))
 	view.SetEnv(data.Config.Env)
 	for filename, content := range data.Config.Overlay {
 		session.SetOverlay(span.FileURI(filename), content)
@@ -59,6 +61,7 @@ func testLSP(t *testing.T, exporter packagestest.Exporter) {
 			hoverKind: source.SynopsisDocumentation,
 		},
 		data: data,
+		ctx:  ctx,
 	}
 	tests.Run(t, r, data)
 }
@@ -67,15 +70,15 @@ func testLSP(t *testing.T, exporter packagestest.Exporter) {
 func (r *runner) Diagnostics(t *testing.T, data tests.Diagnostics) {
 	v := r.server.session.View(viewName)
 	for uri, want := range data {
-		f, err := v.GetFile(context.Background(), uri)
+		f, err := v.GetFile(r.ctx, uri)
 		if err != nil {
 			t.Fatalf("no file for %s: %v", f, err)
 		}
 		gof, ok := f.(source.GoFile)
 		if !ok {
 			t.Fatalf("%s is not a Go file: %v", uri, err)
 		}
-		results, err := source.Diagnostics(context.Background(), v, gof, nil)
+		results, err := source.Diagnostics(r.ctx, v, gof, nil)
 		if err != nil {
 			t.Fatal(err)
 		}
@@ -218,7 +221,7 @@ func (r *runner) Completion(t *testing.T, data tests.Completions, snippets tests
 
 func (r *runner) runCompletion(t *testing.T, src span.Span) *protocol.CompletionList {
 	t.Helper()
-	list, err := r.server.Completion(context.Background(), &protocol.CompletionParams{
+	list, err := r.server.Completion(r.ctx, &protocol.CompletionParams{
 		TextDocumentPositionParams: protocol.TextDocumentPositionParams{
 			TextDocument: protocol.TextDocumentIdentifier{
 				URI: protocol.NewURI(src.URI()),
@@ -295,7 +298,6 @@ func summarizeCompletionItems(i int, want []source.CompletionItem, got []protoco
 }
 
 func (r *runner) Format(t *testing.T, data tests.Formats) {
-	ctx := context.Background()
 	for _, spn := range data {
 		uri := spn.URI()
 		filename := uri.Filename()
@@ -305,7 +307,7 @@ func (r *runner) Format(t *testing.T, data tests.Formats) {
 			return out, nil
 		}))
 
-		edits, err := r.server.Formatting(context.Background(), &protocol.DocumentFormattingParams{
+		edits, err := r.server.Formatting(r.ctx, &protocol.DocumentFormattingParams{
 			TextDocument: protocol.TextDocumentIdentifier{
 				URI: protocol.NewURI(uri),
 			},
@@ -316,7 +318,7 @@ func (r *runner) Format(t *testing.T, data tests.Formats) {
 			}
 			continue
 		}
-		_, m, err := getSourceFile(ctx, r.server.session.ViewOf(uri), uri)
+		_, m, err := getSourceFile(r.ctx, r.server.session.ViewOf(uri), uri)
 		if err != nil {
 			t.Error(err)
 		}
@@ -333,7 +335,6 @@ func (r *runner) Format(t *testing.T, data tests.Formats) {
 }
 
 func (r *runner) Import(t *testing.T, data tests.Imports) {
-	ctx := context.Background()
 	for _, spn := range data {
 		uri := spn.URI()
 		filename := uri.Filename()
@@ -343,7 +344,7 @@ func (r *runner) Import(t *testing.T, data tests.Imports) {
 			return out, nil
 		}))
 
-		actions, err := r.server.CodeAction(context.Background(), &protocol.CodeActionParams{
+		actions, err := r.server.CodeAction(r.ctx, &protocol.CodeActionParams{
 			TextDocument: protocol.TextDocumentIdentifier{
 				URI: protocol.NewURI(uri),
 			},
@@ -354,7 +355,7 @@ func (r *runner) Import(t *testing.T, data tests.Imports) {
 			}
 			continue
 		}
-		_, m, err := getSourceFile(ctx, r.server.session.ViewOf(uri), uri)
+		_, m, err := getSourceFile(r.ctx, r.server.session.ViewOf(uri), uri)
 		if err != nil {
 			t.Error(err)
 		}
@@ -393,13 +394,13 @@ func (r *runner) Definition(t *testing.T, data tests.Definitions) {
 		var locs []protocol.Location
 		var hover *protocol.Hover
 		if d.IsType {
-			locs, err = r.server.TypeDefinition(context.Background(), params)
+			locs, err = r.server.TypeDefinition(r.ctx, params)
 		} else {
-			locs, err = r.server.Definition(context.Background(), params)
+			locs, err = r.server.Definition(r.ctx, params)
 			if err != nil {
 				t.Fatalf("failed for %v: %v", d.Src, err)
 			}
-			hover, err = r.server.Hover(context.Background(), params)
+			hover, err = r.server.Hover(r.ctx, params)
 		}
 		if err != nil {
 			t.Fatalf("failed for %v: %v", d.Src, err)
@@ -446,7 +447,7 @@ func (r *runner) Highlight(t *testing.T, data tests.Highlights) {
 			TextDocument: protocol.TextDocumentIdentifier{URI: loc.URI},
 			Position:     loc.Range.Start,
 		}
-		highlights, err := r.server.DocumentHighlight(context.Background(), params)
+		highlights, err := r.server.DocumentHighlight(r.ctx, params)
 		if err != nil {
 			t.Fatal(err)
 		}
@@ -492,7 +493,7 @@ func (r *runner) Reference(t *testing.T, data tests.References) {
 				Position:     loc.Range.Start,
 			},
 		}
-		got, err := r.server.References(context.Background(), params)
+		got, err := r.server.References(r.ctx, params)
 		if err != nil {
 			t.Fatalf("failed for %v: %v", src, err)
 		}
@@ -509,7 +510,6 @@ func (r *runner) Reference(t *testing.T, data tests.References) {
 }
 
 func (r *runner) Rename(t *testing.T, data tests.Renames) {
-	ctx := context.Background()
 	for spn, newText := range data {
 		tag := fmt.Sprintf("%s-rename", newText)
 
@@ -524,7 +524,7 @@ func (r *runner) Rename(t *testing.T, data tests.Renames) {
 			t.Fatalf("failed for %v: %v", spn, err)
 		}
 
-		workspaceEdits, err := r.server.Rename(ctx, &protocol.RenameParams{
+		workspaceEdits, err := r.server.Rename(r.ctx, &protocol.RenameParams{
 			TextDocument: protocol.TextDocumentIdentifier{
 				URI: protocol.NewURI(uri),
 			},
@@ -544,7 +544,7 @@ func (r *runner) Rename(t *testing.T, data tests.Renames) {
 		var res []string
 		for uri, edits := range *workspaceEdits.Changes {
 			spnURI := span.URI(uri)
-			_, m, err := getSourceFile(ctx, r.server.session.ViewOf(span.URI(spnURI)), spnURI)
+			_, m, err := getSourceFile(r.ctx, r.server.session.ViewOf(span.URI(spnURI)), spnURI)
 			if err != nil {
 				t.Error(err)
 			}
@@ -612,7 +612,7 @@ func (r *runner) Symbol(t *testing.T, data tests.Symbols) {
 				URI: string(uri),
 			},
 		}
-		symbols, err := r.server.DocumentSymbol(context.Background(), params)
+		symbols, err := r.server.DocumentSymbol(r.ctx, params)
 		if err != nil {
 			t.Fatal(err)
 		}
@@ -688,7 +688,7 @@ func (r *runner) SignatureHelp(t *testing.T, data tests.Signatures) {
 		if err != nil {
 			t.Fatalf("failed for %v: %v", loc, err)
 		}
-		gotSignatures, err := r.server.SignatureHelp(context.Background(), &protocol.TextDocumentPositionParams{
+		gotSignatures, err := r.server.SignatureHelp(r.ctx, &protocol.TextDocumentPositionParams{
 			TextDocument: protocol.TextDocumentIdentifier{
 				URI: protocol.NewURI(spn.URI()),
 			},
@@ -754,7 +754,7 @@ func (r *runner) Link(t *testing.T, data tests.Links) {
 		if err != nil {
 			t.Fatal(err)
 		}
-		gotLinks, err := r.server.DocumentLink(context.Background(), &protocol.DocumentLinkParams{
+		gotLinks, err := r.server.DocumentLink(r.ctx, &protocol.DocumentLinkParams{
 			TextDocument: protocol.TextDocumentIdentifier{
 				URI: protocol.NewURI(uri),
 			},

internal/lsp/protocol/detatch.go

@@ -10,13 +10,14 @@ import (
 	"golang.org/x/tools/internal/jsonrpc2"
 	"golang.org/x/tools/internal/lsp/telemetry/trace"
 	"golang.org/x/tools/internal/lsp/xlog"
+	"golang.org/x/tools/internal/xcontext"
 )
 
 const defaultMessageBufferSize = 20
 const defaultRejectIfOverloaded = false
 
 func canceller(ctx context.Context, conn *jsonrpc2.Conn, id jsonrpc2.ID) {
-	ctx = detatchContext(ctx)
+	ctx = xcontext.Detach(ctx)
 	ctx, span := trace.StartSpan(ctx, "protocol.canceller")
 	defer span.End()
 	conn.Notify(ctx, "$/cancelRequest", &CancelParams{ID: id})