gopls/internal/span: identify span.URI and protocol.DocumentURI

Before, the difference between these two types was that DocumentURI
may contain various VS Code encoding mistakes (e.g. %XX, file://)
whereas span.URI was "clean". However, there was little clarity
as to when and how often the cleaning process was applied to
DocumentURIs received off the wire.

This change makes span.URI an alias for DocumentURI;
a followup will inline it away. The clean-up is now done
during JSON decoding, ensuring that all DocumentURIs areu
cleaned once and only once.

It is not necessary to "dirty" URIs before sending them
back in responses to the client, even if they arrived dirty.

Fixes golang/go#64147

Change-Id: Iea262b1b8867c26df541e43f77c2c5ba4f7e81c0
Reviewed-on: https://go-review.googlesource.com/c/tools/+/542616
Reviewed-by: Robert Findley <rfindley@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>

gopls/internal/cmd/cmd.go

@@ -31,6 +31,7 @@ import (
 	"golang.org/x/tools/gopls/internal/lsp/protocol"
 	"golang.org/x/tools/gopls/internal/lsp/source"
 	"golang.org/x/tools/gopls/internal/span"
+	"golang.org/x/tools/internal/constraints"
 	"golang.org/x/tools/internal/diff"
 	"golang.org/x/tools/internal/jsonrpc2"
 	"golang.org/x/tools/internal/tool"
@@ -453,15 +454,6 @@ func newConnection(server protocol.Server, client *cmdClient) *connection {
 	}
 }
 
-// fileURI converts a DocumentURI to a file:// span.URI, panicking if it's not a file.
-func fileURI(uri protocol.DocumentURI) span.URI {
-	sURI := uri.SpanURI()
-	if !sURI.IsFile() {
-		panic(fmt.Sprintf("%q is not a file URI", uri))
-	}
-	return sURI
-}
-
 func (c *cmdClient) CodeLensRefresh(context.Context) error { return nil }
 
 func (c *cmdClient) LogTrace(context.Context, *protocol.LogTraceParams) error { return nil }
@@ -556,23 +548,22 @@ func (c *cmdClient) ApplyEdit(ctx context.Context, p *protocol.ApplyWorkspaceEdi
 // files, honoring the preferred edit mode specified by cli.app.editMode.
 // (Used by rename and by ApplyEdit downcalls.)
 func (cli *cmdClient) applyWorkspaceEdit(edit *protocol.WorkspaceEdit) error {
-	var orderedURIs []string
+	var orderedURIs []span.URI
 	edits := map[span.URI][]protocol.TextEdit{}
 	for _, c := range edit.DocumentChanges {
 		if c.TextDocumentEdit != nil {
-			uri := fileURI(c.TextDocumentEdit.TextDocument.URI)
+			uri := c.TextDocumentEdit.TextDocument.URI
 			edits[uri] = append(edits[uri], c.TextDocumentEdit.Edits...)
-			orderedURIs = append(orderedURIs, string(uri))
+			orderedURIs = append(orderedURIs, uri)
 		}
 		if c.RenameFile != nil {
 			return fmt.Errorf("client does not support file renaming (%s -> %s)",
 				c.RenameFile.OldURI,
 				c.RenameFile.NewURI)
 		}
 	}
-	sort.Strings(orderedURIs)
-	for _, u := range orderedURIs {
-		uri := span.URIFromURI(u)
+	sortSlice(orderedURIs)
+	for _, uri := range orderedURIs {
 		f := cli.openFile(uri)
 		if f.err != nil {
 			return f.err
@@ -584,6 +575,10 @@ func (cli *cmdClient) applyWorkspaceEdit(edit *protocol.WorkspaceEdit) error {
 	return nil
 }
 
+func sortSlice[T constraints.Ordered](slice []T) {
+	sort.Slice(slice, func(i, j int) bool { return slice[i] < slice[j] })
+}
+
 // applyTextEdits applies a list of edits to the mapper file content,
 // using the preferred edit mode. It is a no-op if there are no edits.
 func applyTextEdits(mapper *protocol.Mapper, edits []protocol.TextEdit, flags *EditFlags) error {
@@ -641,7 +636,7 @@ func (c *cmdClient) PublishDiagnostics(ctx context.Context, p *protocol.PublishD
 	c.filesMu.Lock()
 	defer c.filesMu.Unlock()
 
-	file := c.getFile(fileURI(p.URI))
+	file := c.getFile(p.URI)
 	file.diagnostics = append(file.diagnostics, p.Diagnostics...)
 
 	// Perform a crude in-place deduplication.

gopls/internal/cmd/definition.go

@@ -98,7 +98,7 @@ func (d *definition) Run(ctx context.Context, args ...string) error {
 	if len(locs) == 0 {
 		return fmt.Errorf("%v: not an identifier", from)
 	}
-	file, err = conn.openFile(ctx, fileURI(locs[0].URI))
+	file, err = conn.openFile(ctx, locs[0].URI)
 	if err != nil {
 		return fmt.Errorf("%v: %v", from, err)
 	}

gopls/internal/cmd/implementation.go

@@ -66,7 +66,7 @@ func (i *implementation) Run(ctx context.Context, args ...string) error {
 
 	var spans []string
 	for _, impl := range implementations {
-		f, err := conn.openFile(ctx, fileURI(impl.URI))
+		f, err := conn.openFile(ctx, impl.URI)
 		if err != nil {
 			return err
 		}

gopls/internal/cmd/imports.go

@@ -70,7 +70,7 @@ func (t *imports) Run(ctx context.Context, args ...string) error {
 		}
 		for _, c := range a.Edit.DocumentChanges {
 			if c.TextDocumentEdit != nil {
-				if fileURI(c.TextDocumentEdit.TextDocument.URI) == uri {
+				if c.TextDocumentEdit.TextDocument.URI == uri {
 					edits = append(edits, c.TextDocumentEdit.Edits...)
 				}
 			}

gopls/internal/cmd/references.go

@@ -70,7 +70,7 @@ func (r *references) Run(ctx context.Context, args ...string) error {
 	}
 	var spans []string
 	for _, l := range locations {
-		f, err := conn.openFile(ctx, fileURI(l.URI))
+		f, err := conn.openFile(ctx, l.URI)
 		if err != nil {
 			return err
 		}

gopls/internal/cmd/suggested_fix.go

@@ -154,7 +154,7 @@ func (s *suggestedFix) Run(ctx context.Context, args ...string) error {
 		if !from.HasPosition() {
 			for _, c := range a.Edit.DocumentChanges {
 				if c.TextDocumentEdit != nil {
-					if fileURI(c.TextDocumentEdit.TextDocument.URI) == uri {
+					if c.TextDocumentEdit.TextDocument.URI == uri {
 						edits = append(edits, c.TextDocumentEdit.Edits...)
 					}
 				}
@@ -168,7 +168,7 @@ func (s *suggestedFix) Run(ctx context.Context, args ...string) error {
 			if diag.Range.Start == rng.Start {
 				for _, c := range a.Edit.DocumentChanges {
 					if c.TextDocumentEdit != nil {
-						if fileURI(c.TextDocumentEdit.TextDocument.URI) == uri {
+						if c.TextDocumentEdit.TextDocument.URI == uri {
 							edits = append(edits, c.TextDocumentEdit.Edits...)
 						}
 					}
@@ -181,7 +181,7 @@ func (s *suggestedFix) Run(ctx context.Context, args ...string) error {
 		if len(a.Diagnostics) == 0 {
 			for _, c := range a.Edit.DocumentChanges {
 				if c.TextDocumentEdit != nil {
-					if fileURI(c.TextDocumentEdit.TextDocument.URI) == uri {
+					if c.TextDocumentEdit.TextDocument.URI == uri {
 						edits = append(edits, c.TextDocumentEdit.Edits...)
 					}
 				}

gopls/internal/cmd/workspace_symbol.go

@@ -74,7 +74,7 @@ func (r *workspaceSymbol) Run(ctx context.Context, args ...string) error {
 		return err
 	}
 	for _, s := range symbols {
-		f, err := conn.openFile(ctx, fileURI(s.Location.URI))
+		f, err := conn.openFile(ctx, s.Location.URI)
 		if err != nil {
 			return err
 		}

gopls/internal/lsp/general.go

@@ -93,7 +93,7 @@ func (s *server) initialize(ctx context.Context, params *protocol.ParamInitializ
 		}
 	}
 	for _, folder := range folders {
-		uri := span.URIFromURI(folder.URI)
+		uri := protocol.URIFromURI(folder.URI)
 		if !uri.IsFile() {
 			continue
 		}
@@ -305,7 +305,7 @@ func (s *server) addFolders(ctx context.Context, folders []protocol.WorkspaceFol
 	// Only one view gets to have a workspace.
 	var nsnapshots sync.WaitGroup // number of unfinished snapshot initializations
 	for _, folder := range folders {
-		uri := span.URIFromURI(folder.URI)
+		uri := protocol.URIFromURI(folder.URI)
 		// Ignore non-file URIs.
 		if !uri.IsFile() {
 			continue

gopls/internal/lsp/protocol/generate/output.go

@@ -258,6 +258,9 @@ func genStructs(model Model) {
 //    file:///c:/project/readme.md
 //    file:///C%3A/project/readme.md
 //
+// This is done during JSON unmarshalling;
+// see [DocumentURI.UnmarshalText] for details.
+//
 type DocumentURI string
 `
 	types["URI"] = `// A URI is an arbitrary URL (e.g. https), not necessarily a file.

gopls/internal/lsp/protocol/mapper.go

@@ -72,7 +72,6 @@ import (
 	"unicode/utf8"
 
 	"golang.org/x/tools/gopls/internal/lsp/safetoken"
-	"golang.org/x/tools/gopls/internal/span"
 )
 
 // A Mapper wraps the content of a file and provides mapping
@@ -94,7 +93,7 @@ import (
 //
 // See overview comments at top of this file.
 type Mapper struct {
-	URI     span.URI
+	URI     DocumentURI
 	Content []byte
 
 	// Line-number information is requested only for a tiny
@@ -109,7 +108,7 @@ type Mapper struct {
 }
 
 // NewMapper creates a new mapper for the given URI and content.
-func NewMapper(uri span.URI, content []byte) *Mapper {
+func NewMapper(uri DocumentURI, content []byte) *Mapper {
 	return &Mapper{URI: uri, Content: content}
 }
 
@@ -392,7 +391,7 @@ func (mr MappedRange) Offsets() (start, end int) { return mr.start, mr.end }
 // -- convenience functions --
 
 // URI returns the URI of the range's file.
-func (mr MappedRange) URI() span.URI {
+func (mr MappedRange) URI() DocumentURI {
 	return mr.Mapper.URI
 }
 

gopls/internal/lsp/protocol/mapper_test.go

@@ -10,7 +10,6 @@ import (
 	"testing"
 
 	"golang.org/x/tools/gopls/internal/lsp/protocol"
-	"golang.org/x/tools/gopls/internal/span"
 )
 
 // This file tests Mapper's logic for converting between offsets,
@@ -437,7 +436,7 @@ func TestBytesOffset(t *testing.T) {
 
 	for i, test := range tests {
 		fname := fmt.Sprintf("test %d", i)
-		uri := span.URIFromPath(fname)
+		uri := protocol.URIFromPath(fname)
 		mapper := protocol.NewMapper(uri, []byte(test.text))
 		got, err := mapper.PositionOffset(test.pos)
 		if err != nil && test.want != -1 {

gopls/internal/lsp/protocol/span.go

@@ -7,22 +7,8 @@ package protocol
 import (
 	"fmt"
 	"unicode/utf8"
-
-	"golang.org/x/tools/gopls/internal/span"
 )
 
-func URIFromSpanURI(uri span.URI) DocumentURI {
-	return DocumentURI(uri) // simple conversion
-}
-
-func URIFromPath(path string) DocumentURI {
-	return URIFromSpanURI(span.URIFromPath(path)) // normalizing conversion
-}
-
-func (u DocumentURI) SpanURI() span.URI {
-	return span.URIFromURI(string(u)) // normalizing conversion
-}
-
 // CompareLocation defines a three-valued comparison over locations,
 // lexicographically ordered by (URI, Range).
 func CompareLocation(x, y Location) int {