internal/lsp: push more build-specific logic into the view

The view should really be able to determine if it's valid, not the
source package. Expand moduleInformation to be buildInfo, and use it to
collect additional details.

Use this information to determine if we should load a view's
subdirectories as part of the initial workspace load. If a module is
initialized, we will recreate the view, so we should be fine. Not sure
what will happen if the directory is moved into GOPATH, but that should
be less of a concern (I think).

Fixes golang/go#35818.

Change-Id: Ic8ceedd37386b1653b8965c64d9ba8953778ab78
Reviewed-on: https://go-review.googlesource.com/c/tools/+/216143
Run-TryBot: Rebecca Stambler <rstambler@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Heschi Kreinick <heschi@google.com>

internal/lsp/cache/load.go

@@ -62,6 +62,14 @@ func (s *snapshot) load(ctx context.Context, scopes ...interface{}) ([]*metadata
 				q = "./..."
 			}
 			query = append(query, q)
+		case viewLoadScope:
+			// If we are outside of GOPATH, a module, or some other known
+			// build system, don't load subdirectories.
+			if !s.view.hasValidBuildConfiguration {
+				query = append(query, "./")
+			} else {
+				query = append(query, "./...")
+			}
 		default:
 			panic(fmt.Sprintf("unknown scope type %T", scope))
 		}
@@ -136,9 +144,9 @@ func (s *snapshot) updateMetadata(ctx context.Context, scopes []interface{}, pkg
 		// Don't log output for full workspace packages.Loads.
 		var containsDir bool
 		for _, scope := range scopes {
-			if _, ok := scope.(directoryURI); ok {
+			switch scope.(type) {
+			case directoryURI, viewLoadScope:
 				containsDir = true
-				break
 			}
 		}
 		if !containsDir || s.view.Options().VerboseOutput {

internal/lsp/cache/pkg.go

@@ -40,6 +40,7 @@ type packagePath string
 // Declare explicit types for files and directories to distinguish between the two.
 type fileURI span.URI
 type directoryURI span.URI
+type viewLoadScope span.URI
 
 func (p *pkg) ID() string {
 	return string(p.id)

internal/lsp/cache/session.go

@@ -105,14 +105,8 @@ func (s *session) createView(ctx context.Context, name string, folder span.URI,
 	if v.session.cache.options != nil {
 		v.session.cache.options(&v.options)
 	}
-
-	// Make sure to get the `go env` before continuing with initialization.
-	gomod, err := v.setGoEnv(ctx, folder.Filename(), options.Env)
-	if err != nil {
-		return nil, nil, err
-	}
 	// Set the module-specific information.
-	if err := v.setModuleInformation(ctx, gomod, v.options.TempModfile); err != nil {
+	if err := v.setBuildInformation(ctx, folder, options.Env, v.options.TempModfile); err != nil {
 		return nil, nil, err
 	}
 

internal/lsp/cache/view.go

@@ -60,9 +60,6 @@ type view struct {
 	// Folder is the root of this view.
 	folder span.URI
 
-	// mod is the module information for this view.
-	mod moduleInformation
-
 	// importsMu guards imports-related state, particularly the ProcessEnv.
 	importsMu sync.Mutex
 	// process is the process env for this view.
@@ -88,9 +85,6 @@ type view struct {
 	ignoredURIsMu sync.Mutex
 	ignoredURIs   map[span.URI]struct{}
 
-	// `go env` variables that need to be tracked by the view.
-	gopath, gocache string
-
 	// initialized is closed when the view has been fully initialized.
 	// On initialization, the view's workspace packages are loaded.
 	// All of the fields below are set as part of initialization.
@@ -101,6 +95,21 @@ type view struct {
 
 	// builtin pins the AST and package for builtin.go in memory.
 	builtin *builtinPackageHandle
+
+	// True if the view is either in GOPATH, a module, or some other
+	// non go command build system.
+	hasValidBuildConfiguration bool
+
+	// The real and temporary go.mod files that are attributed to a view.
+	// The temporary go.mod is for use with the Go command's -modfile flag.
+	realMod, tempMod span.URI
+
+	// goCommand indicates if the user is using the go command or some other
+	// build system.
+	goCommand bool
+
+	// `go env` variables that need to be tracked.
+	gopath, gocache string
 }
 
 type builtinPackageHandle struct {
@@ -137,14 +146,12 @@ func (f *fileBase) addURI(uri span.URI) int {
 	return len(f.uris)
 }
 
-// moduleInformation holds the real and temporary go.mod files
-// that are attributed to a view.
-type moduleInformation struct {
-	realMod, tempMod span.URI
+func (v *view) ValidBuildConfiguration() bool {
+	return v.hasValidBuildConfiguration
 }
 
 func (v *view) ModFiles() (span.URI, span.URI) {
-	return v.mod.realMod, v.mod.tempMod
+	return v.realMod, v.tempMod
 }
 
 func (v *view) Session() source.Session {
@@ -257,8 +264,8 @@ func (v *view) Config(ctx context.Context) *packages.Config {
 	// We want to run the go commands with the -modfile flag if the version of go
 	// that we are using supports it.
 	buildFlags := v.options.BuildFlags
-	if v.mod.tempMod != "" {
-		buildFlags = append(buildFlags, fmt.Sprintf("-modfile=%s", v.mod.tempMod.Filename()))
+	if v.tempMod != "" {
+		buildFlags = append(buildFlags, fmt.Sprintf("-modfile=%s", v.tempMod.Filename()))
 	}
 	cfg := &packages.Config{
 		Dir:        v.folder.Filename(),
@@ -299,8 +306,8 @@ func (v *view) RunProcessEnvFunc(ctx context.Context, fn func(*imports.Options)
 	}
 
 	// In module mode, check if the mod file has changed.
-	if v.mod.realMod != "" {
-		mod, err := v.Snapshot().GetFile(v.mod.realMod)
+	if v.realMod != "" {
+		mod, err := v.Snapshot().GetFile(v.realMod)
 		if err == nil && mod.Identity() != v.cachedModFileVersion {
 			v.processEnv.GetResolver().(*imports.ModuleResolver).ClearForNewMod()
 			v.cachedModFileVersion = mod.Identity()
@@ -488,9 +495,9 @@ func (v *view) shutdown(context.Context) {
 		v.cancel()
 		v.cancel = nil
 	}
-	if v.mod.tempMod != "" {
-		os.Remove(v.mod.tempMod.Filename())
-		os.Remove(tempSumFile(v.mod.tempMod.Filename()))
+	if v.tempMod != "" {
+		os.Remove(v.tempMod.Filename())
+		os.Remove(tempSumFile(v.tempMod.Filename()))
 	}
 	debug.DropView(debugView{v})
 }
@@ -543,7 +550,7 @@ func (v *view) initialize(ctx context.Context, s *snapshot) {
 
 		v.initializationError = func() error {
 			// Do not cancel the call to go/packages.Load for the entire workspace.
-			meta, err := s.load(ctx, directoryURI(v.folder), packagePath("builtin"))
+			meta, err := s.load(ctx, viewLoadScope("LOAD_VIEW"), packagePath("builtin"))
 			if err != nil {
 				return err
 			}
@@ -611,81 +618,22 @@ func (v *view) cancelBackground() {
 	v.backgroundCtx, v.cancel = context.WithCancel(v.baseCtx)
 }
 
-// setGoEnv sets the view's GOPATH and GOCACHE values.
-// It also returns the view's GOMOD value, which need not be cached.
-func (v *view) setGoEnv(ctx context.Context, dir string, env []string) (string, error) {
-	var gocache, gopath bool
-	for _, e := range env {
-		split := strings.Split(e, "=")
-		if len(split) != 2 {
-			continue
-		}
-		switch split[0] {
-		case "GOCACHE":
-			v.gocache = split[1]
-			gocache = true
-		case "GOPATH":
-			v.gopath = split[1]
-			gopath = true
-		}
-	}
-	b, err := source.InvokeGo(ctx, dir, env, "env", "-json")
+func (v *view) setBuildInformation(ctx context.Context, folder span.URI, env []string, modfileFlagEnabled bool) error {
+	// Make sure to get the `go env` before continuing with initialization.
+	gomod, err := v.getGoEnv(ctx, env)
 	if err != nil {
-		return "", err
+		return err
 	}
-	envMap := make(map[string]string)
-	decoder := json.NewDecoder(b)
-	if err := decoder.Decode(&envMap); err != nil {
-		return "", err
-	}
-	if !gopath {
-		if gopath, ok := envMap["GOPATH"]; ok {
-			v.gopath = gopath
-		} else {
-			return "", errors.New("unable to determine GOPATH")
-		}
-	}
-	if !gocache {
-		if gocache, ok := envMap["GOCACHE"]; ok {
-			v.gocache = gocache
-		} else {
-			return "", errors.New("unable to determine GOCACHE")
-		}
-	}
-	if gomod, ok := envMap["GOMOD"]; ok {
-		return gomod, nil
-	}
-	return "", nil
-}
-
-// This function will return the main go.mod file for this folder if it exists and whether the -modfile
-// flag exists for this version of go.
-func (v *view) modfileFlagExists(ctx context.Context, env []string) (bool, error) {
-	// Check the go version by running "go list" with modules off.
-	// Borrowed from internal/imports/mod.go:620.
-	const format = `{{range context.ReleaseTags}}{{if eq . "go1.14"}}{{.}}{{end}}{{end}}`
-	folder := v.folder.Filename()
-	stdout, err := source.InvokeGo(ctx, folder, append(env, "GO111MODULE=off"), "list", "-e", "-f", format)
-	if err != nil {
-		return false, err
-	}
-	// If the output is not go1.14 or an empty string, then it could be an error.
-	lines := strings.Split(stdout.String(), "\n")
-	if len(lines) < 2 && stdout.String() != "" {
-		log.Error(ctx, "unexpected stdout when checking for go1.14", errors.Errorf("%q", stdout), telemetry.Directory.Of(folder))
-		return false, nil
-	}
-	return lines[0] == "go1.14", nil
-}
-
-func (v *view) setModuleInformation(ctx context.Context, gomod string, modfileFlagEnabled bool) error {
 	modFile := strings.TrimSpace(gomod)
 	if modFile == os.DevNull {
 		return nil
 	}
-	v.mod = moduleInformation{
-		realMod: span.FileURI(modFile),
-	}
+	v.realMod = span.FileURI(modFile)
+
+	// Now that we have set all required fields,
+	// check if the view has a valid build configuration.
+	v.hasValidBuildConfiguration = checkBuildConfiguration(v.goCommand, v.realMod, v.folder, v.gopath)
+
 	// The user has disabled the use of the -modfile flag.
 	if !modfileFlagEnabled {
 		return nil
@@ -713,7 +661,7 @@ func (v *view) setModuleInformation(ctx context.Context, gomod string, modfileFl
 	if _, err := io.Copy(tempModFile, origFile); err != nil {
 		return err
 	}
-	v.mod.tempMod = span.FileURI(tempModFile.Name())
+	v.tempMod = span.FileURI(tempModFile.Name())
 
 	// Copy go.sum file as well (if there is one).
 	sumFile := filepath.Join(filepath.Dir(modFile), "go.sum")
@@ -731,6 +679,108 @@ func (v *view) setModuleInformation(ctx context.Context, gomod string, modfileFl
 	return nil
 }
 
+func checkBuildConfiguration(goCommand bool, mod, folder span.URI, gopath string) bool {
+	// Since we only really understand the `go` command, if the user is not
+	// using the go command, assume that their configuration is valid.
+	if !goCommand {
+		return true
+	}
+	// Check if the user is working within a module.
+	if mod != "" {
+		return true
+	}
+	// The user may have a multiple directories in their GOPATH.
+	// Check if the workspace is within any of them.
+	for _, gp := range filepath.SplitList(gopath) {
+		if isSubdirectory(filepath.Join(gp, "src"), folder.Filename()) {
+			return true
+		}
+	}
+	return false
+}
+
+func isSubdirectory(root, leaf string) bool {
+	rel, err := filepath.Rel(root, leaf)
+	return err == nil && !strings.HasPrefix(rel, "..")
+}
+
+// getGoEnv sets the view's build information's GOPATH, GOCACHE, and GOPACKAGESDRIVER values.
+// It also returns the view's GOMOD value, which need not be cached.
+func (v *view) getGoEnv(ctx context.Context, env []string) (string, error) {
+	var gocache, gopath, gopackagesdriver bool
+	isGoCommand := func(gopackagesdriver string) bool {
+		return gopackagesdriver == "" || gopackagesdriver == "off"
+	}
+	for _, e := range env {
+		split := strings.Split(e, "=")
+		if len(split) != 2 {
+			continue
+		}
+		switch split[0] {
+		case "GOCACHE":
+			v.gocache = split[1]
+			gocache = true
+		case "GOPATH":
+			v.gopath = split[1]
+			gopath = true
+		case "GOPACKAGESDRIVER":
+			v.goCommand = isGoCommand(split[1])
+			gopackagesdriver = true
+		}
+	}
+	b, err := source.InvokeGo(ctx, v.folder.Filename(), env, "env", "-json")
+	if err != nil {
+		return "", err
+	}
+	envMap := make(map[string]string)
+	decoder := json.NewDecoder(b)
+	if err := decoder.Decode(&envMap); err != nil {
+		return "", err
+	}
+	if !gopath {
+		if gopath, ok := envMap["GOPATH"]; ok {
+			v.gopath = gopath
+		} else {
+			return "", errors.New("unable to determine GOPATH")
+		}
+	}
+	if !gocache {
+		if gocache, ok := envMap["GOCACHE"]; ok {
+			v.gocache = gocache
+		} else {
+			return "", errors.New("unable to determine GOCACHE")
+		}
+	}
+	// The value of GOPACKAGESDRIVER is not returned through the go command.
+	if !gopackagesdriver {
+		v.goCommand = isGoCommand(os.Getenv("GOPACKAGESDRIVER"))
+	}
+	if gomod, ok := envMap["GOMOD"]; ok {
+		return gomod, nil
+	}
+	return "", nil
+}
+
+// This function will return the main go.mod file for this folder if it exists and whether the -modfile
+// flag exists for this version of go.
+func (v *view) modfileFlagExists(ctx context.Context, env []string) (bool, error) {
+	// Check the go version by running "go list" with modules off.
+	// Borrowed from internal/imports/mod.go:620.
+	const format = `{{range context.ReleaseTags}}{{if eq . "go1.14"}}{{.}}{{end}}{{end}}`
+	folder := v.folder.Filename()
+	stdout, err := source.InvokeGo(ctx, folder, append(env, "GO111MODULE=off"), "list", "-e", "-f", format)
+	if err != nil {
+		return false, err
+	}
+	// If the output is not go1.14 or an empty string, then it could be an error.
+	lines := strings.Split(stdout.String(), "\n")
+	if len(lines) < 2 && stdout.String() != "" {
+		log.Error(ctx, "unexpected stdout when checking for go1.14", errors.Errorf("%q", stdout), telemetry.Directory.Of(folder))
+		return false, nil
+	}
+	return lines[0] == "go1.14", nil
+}
+
 // tempSumFile returns the path to the copied temporary go.sum file.
 // It simply replaces the extension of the temporary go.mod file with "sum".
 func tempSumFile(filename string) string {

internal/lsp/source/view.go

@@ -133,6 +133,11 @@ type View interface {
 
 	// Rebuild rebuilds the current view, replacing the original view in its session.
 	Rebuild(ctx context.Context) (Snapshot, error)
+
+	// InvalidBuildConfiguration returns true if there is some error in the
+	// user's workspace. In particular, if they are both outside of a module
+	// and their GOPATH.
+	ValidBuildConfiguration() bool
 }
 
 // Session represents a single connection from a client.