internal/lsp: support renaming import specs

Support the renaming of the imported name of a package within a file.
This case needs to be special cased because the ident may be added or
removed.

Change-Id: I333bc2b2ca5ce81c4a2afb8b10035f525dfad464
Reviewed-on: https://go-review.googlesource.com/c/tools/+/184199
Run-TryBot: Suzy Mueller <suzmue@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Rebecca Stambler <rstambler@golang.org>

internal/lsp/source/rename.go

@@ -5,9 +5,11 @@
 package source
 
 import (
+	"bytes"
 	"context"
 	"fmt"
 	"go/ast"
+	"go/format"
 	"go/token"
 	"go/types"
 	"regexp"
@@ -49,11 +51,6 @@ func (i *IdentifierInfo) Rename(ctx context.Context, newName string) (map[span.U
 		return nil, fmt.Errorf("failed to rename because %q is declared in package %q", i.Name, i.decl.obj.Pkg().Name())
 	}
 
-	// TODO(suzmue): Support renaming of imported packages.
-	if _, ok := i.decl.obj.(*types.PkgName); ok {
-		return nil, fmt.Errorf("renaming imported package %s not supported", i.Name)
-	}
-
 	refs, err := i.References(ctx)
 	if err != nil {
 		return nil, err
@@ -96,6 +93,18 @@ func (r *renamer) update() (map[span.URI][]TextEdit, error) {
 			return nil, err
 		}
 
+		// Renaming a types.PkgName may result in the addition or removal of an identifier,
+		// so we deal with this separately.
+		if pkgName, ok := ref.obj.(*types.PkgName); ok && ref.isDeclaration {
+			edit, err := r.updatePkgName(pkgName)
+			if err != nil {
+				return nil, err
+			}
+			result[refSpan.URI()] = append(result[refSpan.URI()], *edit)
+			continue
+		}
+
+		// Replace the identifier with r.to.
 		edit := TextEdit{
 			Span:    refSpan,
 			NewText: r.to,
@@ -103,16 +112,16 @@ func (r *renamer) update() (map[span.URI][]TextEdit, error) {
 
 		result[refSpan.URI()] = append(result[refSpan.URI()], edit)
 
-		if !ref.isDeclaration || ref.ident == nil { // done if it it is a use or does not have an identifier
+		if !ref.isDeclaration || ref.ident == nil { // uses do not have doc comments to update.
 			continue
 		}
 
 		doc := r.docComment(r.pkg, ref.ident)
-		if doc == nil { // no doc comment
+		if doc == nil {
 			continue
 		}
 
-		// Perform the rename in doc comments declared in the original package
+		// Perform the rename in doc comments declared in the original package.
 		for _, comment := range doc.List {
 			for _, locs := range docRegexp.FindAllStringIndex(comment.Text, -1) {
 				rng := span.NewRange(r.fset, comment.Pos()+token.Pos(locs[0]), comment.Pos()+token.Pos(locs[1]))
@@ -120,7 +129,7 @@ func (r *renamer) update() (map[span.URI][]TextEdit, error) {
 				if err != nil {
 					return nil, err
 				}
-				result[refSpan.URI()] = append(result[refSpan.URI()], TextEdit{
+				result[spn.URI()] = append(result[spn.URI()], TextEdit{
 					Span:    spn,
 					NewText: r.to,
 				})
@@ -159,3 +168,46 @@ func (r *renamer) docComment(pkg Package, id *ast.Ident) *ast.CommentGroup {
 	}
 	return nil
 }
+
+// updatePkgName returns the updates to rename a pkgName in the import spec
+func (r *renamer) updatePkgName(pkgName *types.PkgName) (*TextEdit, error) {
+	// Modify ImportSpec syntax to add or remove the Name as needed.
+	pkg := r.packages[pkgName.Pkg()]
+	_, path, _ := pathEnclosingInterval(r.ctx, r.fset, pkg, pkgName.Pos(), pkgName.Pos())
+
+	if len(path) < 2 {
+		return nil, fmt.Errorf("failed to update PkgName for %s", pkgName.Name())
+	}
+	spec, ok := path[1].(*ast.ImportSpec)
+	if !ok {
+		return nil, fmt.Errorf("failed to update PkgName for %s", pkgName.Name())
+	}
+
+	var astIdent *ast.Ident // will be nil if ident is removed
+	if pkgName.Imported().Name() != r.to {
+		// ImportSpec.Name needed
+		astIdent = &ast.Ident{NamePos: spec.Path.Pos(), Name: r.to}
+	}
+
+	// Make a copy of the ident that just has the name and path.
+	updated := &ast.ImportSpec{
+		Name:   astIdent,
+		Path:   spec.Path,
+		EndPos: spec.EndPos,
+	}
+
+	rng := span.NewRange(r.fset, spec.Pos(), spec.End())
+	spn, err := rng.Span()
+	if err != nil {
+		return nil, err
+	}
+
+	var buf bytes.Buffer
+	format.Node(&buf, r.fset, updated)
+	newText := buf.String()
+
+	return &TextEdit{
+		Span:    spn,
+		NewText: newText,
+	}, nil
+}

internal/lsp/testdata/rename/a/random.go.golden

@@ -1,7 +1,11 @@
 -- GetSum-rename --
 package a
 
-import "fmt"
+import (
+	lg "log"
+	"fmt"
+	f2 "fmt"
+)
 
 func Random() int {
 	y := 6 + 7
@@ -30,18 +34,22 @@ func sw() {
 
 	switch y := x.(type) { //@rename("y", "y0")
 	case int:
-		fmt.Printf("%d", y) //@rename("y", "y1")
+		fmt.Printf("%d", y) //@rename("y", "y1"),rename("fmt", "format")
 	case string:
-		fmt.Printf("%s", y) //@rename("y", "y2")
+		lg.Printf("%s", y) //@rename("y", "y2"),rename("lg","log")
 	default:
-		fmt.Printf("%v", y) //@rename("y", "y3")
+		f2.Printf("%v", y) //@rename("y", "y3"),rename("f2","fmt2")
 	}
 }
 
 -- myX-rename --
 package a
 
-import "fmt"
+import (
+	lg "log"
+	"fmt"
+	f2 "fmt"
+)
 
 func Random() int {
 	y := 6 + 7
@@ -70,18 +78,22 @@ func sw() {
 
 	switch y := x.(type) { //@rename("y", "y0")
 	case int:
-		fmt.Printf("%d", y) //@rename("y", "y1")
+		fmt.Printf("%d", y) //@rename("y", "y1"),rename("fmt", "format")
 	case string:
-		fmt.Printf("%s", y) //@rename("y", "y2")
+		lg.Printf("%s", y) //@rename("y", "y2"),rename("lg","log")
 	default:
-		fmt.Printf("%v", y) //@rename("y", "y3")
+		f2.Printf("%v", y) //@rename("y", "y3"),rename("f2","fmt2")
 	}
 }
 
 -- pos-rename --
 package a
 
-import "fmt"
+import (
+	lg "log"
+	"fmt"
+	f2 "fmt"
+)
 
 func Random() int {
 	y := 6 + 7
@@ -110,18 +122,22 @@ func sw() {
 
 	switch y := x.(type) { //@rename("y", "y0")
 	case int:
-		fmt.Printf("%d", y) //@rename("y", "y1")
+		fmt.Printf("%d", y) //@rename("y", "y1"),rename("fmt", "format")
 	case string:
-		fmt.Printf("%s", y) //@rename("y", "y2")
+		lg.Printf("%s", y) //@rename("y", "y2"),rename("lg","log")
 	default:
-		fmt.Printf("%v", y) //@rename("y", "y3")
+		f2.Printf("%v", y) //@rename("y", "y3"),rename("f2","fmt2")
 	}
 }
 
 -- z-rename --
 package a
 
-import "fmt"
+import (
+	lg "log"
+	"fmt"
+	f2 "fmt"
+)
 
 func Random() int {
 	y := 6 + 7
@@ -150,18 +166,22 @@ func sw() {
 
 	switch y := x.(type) { //@rename("y", "y0")
 	case int:
-		fmt.Printf("%d", y) //@rename("y", "y1")
+		fmt.Printf("%d", y) //@rename("y", "y1"),rename("fmt", "format")
 	case string:
-		fmt.Printf("%s", y) //@rename("y", "y2")
+		lg.Printf("%s", y) //@rename("y", "y2"),rename("lg","log")
 	default:
-		fmt.Printf("%v", y) //@rename("y", "y3")
+		f2.Printf("%v", y) //@rename("y", "y3"),rename("f2","fmt2")
 	}
 }
 
 -- y0-rename --
 package a
 
-import "fmt"
+import (
+	lg "log"
+	"fmt"
+	f2 "fmt"
+)
 
 func Random() int {
 	y := 6 + 7
@@ -190,18 +210,22 @@ func sw() {
 
 	switch y0 := x.(type) { //@rename("y", "y0")
 	case int:
-		fmt.Printf("%d", y0) //@rename("y", "y1")
+		fmt.Printf("%d", y0) //@rename("y", "y1"),rename("fmt", "format")
 	case string:
-		fmt.Printf("%s", y0) //@rename("y", "y2")
+		lg.Printf("%s", y0) //@rename("y", "y2"),rename("lg","log")
 	default:
-		fmt.Printf("%v", y0) //@rename("y", "y3")
+		f2.Printf("%v", y0) //@rename("y", "y3"),rename("f2","fmt2")
 	}
 }
 
 -- y1-rename --
 package a
 
-import "fmt"
+import (
+	lg "log"
+	"fmt"
+	f2 "fmt"
+)
 
 func Random() int {
 	y := 6 + 7
@@ -230,18 +254,22 @@ func sw() {
 
 	switch y1 := x.(type) { //@rename("y", "y0")
 	case int:
-		fmt.Printf("%d", y1) //@rename("y", "y1")
+		fmt.Printf("%d", y1) //@rename("y", "y1"),rename("fmt", "format")
 	case string:
-		fmt.Printf("%s", y1) //@rename("y", "y2")
+		lg.Printf("%s", y1) //@rename("y", "y2"),rename("lg","log")
 	default:
-		fmt.Printf("%v", y1) //@rename("y", "y3")
+		f2.Printf("%v", y1) //@rename("y", "y3"),rename("f2","fmt2")
 	}
 }
 
 -- y2-rename --
 package a
 
-import "fmt"
+import (
+	lg "log"
+	"fmt"
+	f2 "fmt"
+)
 
 func Random() int {
 	y := 6 + 7
@@ -270,18 +298,22 @@ func sw() {
 
 	switch y2 := x.(type) { //@rename("y", "y0")
 	case int:
-		fmt.Printf("%d", y2) //@rename("y", "y1")
+		fmt.Printf("%d", y2) //@rename("y", "y1"),rename("fmt", "format")
 	case string:
-		fmt.Printf("%s", y2) //@rename("y", "y2")
+		lg.Printf("%s", y2) //@rename("y", "y2"),rename("lg","log")
 	default:
-		fmt.Printf("%v", y2) //@rename("y", "y3")
+		f2.Printf("%v", y2) //@rename("y", "y3"),rename("f2","fmt2")
 	}
 }
 
 -- y3-rename --
 package a
 
-import "fmt"
+import (
+	lg "log"
+	"fmt"
+	f2 "fmt"
+)
 
 func Random() int {
 	y := 6 + 7
@@ -310,18 +342,22 @@ func sw() {
 
 	switch y3 := x.(type) { //@rename("y", "y0")
 	case int:
-		fmt.Printf("%d", y3) //@rename("y", "y1")
+		fmt.Printf("%d", y3) //@rename("y", "y1"),rename("fmt", "format")
 	case string:
-		fmt.Printf("%s", y3) //@rename("y", "y2")
+		lg.Printf("%s", y3) //@rename("y", "y2"),rename("lg","log")
 	default:
-		fmt.Printf("%v", y3) //@rename("y", "y3")
+		f2.Printf("%v", y3) //@rename("y", "y3"),rename("f2","fmt2")
 	}
 }
 
 -- format-rename --
 package a
 
-import format "fmt"
+import (
+	lg "log"
+	format "fmt"
+	f2 "fmt"
+)
 
 func Random() int {
 	y := 6 + 7
@@ -350,11 +386,99 @@ func sw() {
 
 	switch y := x.(type) { //@rename("y", "y0")
 	case int:
-		format.Printf("%d", y) //@rename("y", "y1")
+		format.Printf("%d", y) //@rename("y", "y1"),rename("fmt", "format")
 	case string:
-		format.Printf("%s", y) //@rename("y", "y2")
+		lg.Printf("%s", y) //@rename("y", "y2"),rename("lg","log")
 	default:
-		format.Printf("%v", y) //@rename("y", "y3")
+		f2.Printf("%v", y) //@rename("y", "y3"),rename("f2","fmt2")
+	}
+}
+
+-- log-rename --
+package a
+
+import (
+	"log"
+	"fmt"
+	f2 "fmt"
+)
+
+func Random() int {
+	y := 6 + 7
+	return y
+}
+
+func Random2(y int) int { //@rename("y", "z")
+	return y
+}
+
+type Pos struct {
+	x, y int
+}
+
+func (p *Pos) Sum() int {
+	return p.x + p.y //@rename("x", "myX")
+}
+
+func _() {
+	var p Pos   //@rename("p", "pos")
+	_ = p.Sum() //@rename("Sum", "GetSum")
+}
+
+func sw() {
+	var x interface{}
+
+	switch y := x.(type) { //@rename("y", "y0")
+	case int:
+		fmt.Printf("%d", y) //@rename("y", "y1"),rename("fmt", "format")
+	case string:
+		log.Printf("%s", y) //@rename("y", "y2"),rename("lg","log")
+	default:
+		f2.Printf("%v", y) //@rename("y", "y3"),rename("f2","fmt2")
+	}
+}
+
+-- fmt2-rename --
+package a
+
+import (
+	lg "log"
+	"fmt"
+	fmt2 "fmt"
+)
+
+func Random() int {
+	y := 6 + 7
+	return y
+}
+
+func Random2(y int) int { //@rename("y", "z")
+	return y
+}
+
+type Pos struct {
+	x, y int
+}
+
+func (p *Pos) Sum() int {
+	return p.x + p.y //@rename("x", "myX")
+}
+
+func _() {
+	var p Pos   //@rename("p", "pos")
+	_ = p.Sum() //@rename("Sum", "GetSum")
+}
+
+func sw() {
+	var x interface{}
+
+	switch y := x.(type) { //@rename("y", "y0")
+	case int:
+		fmt.Printf("%d", y) //@rename("y", "y1"),rename("fmt", "format")
+	case string:
+		lg.Printf("%s", y) //@rename("y", "y2"),rename("lg","log")
+	default:
+		fmt2.Printf("%v", y) //@rename("y", "y3"),rename("f2","fmt2")
 	}
 }
 

internal/lsp/testdata/rename/a/random.go.in

@@ -1,6 +1,10 @@
 package a
 
-import "fmt"
+import (
+	lg "log"
+	"fmt"
+	f2 "fmt"
+)
 
 func Random() int {
 	y := 6 + 7
@@ -29,10 +33,10 @@ func sw() {
 
 	switch y := x.(type) { //@rename("y", "y0")
 	case int:
-		fmt.Printf("%d", y) //@rename("y", "y1")
+		fmt.Printf("%d", y) //@rename("y", "y1"),rename("fmt", "format")
 	case string:
-		fmt.Printf("%s", y) //@rename("y", "y2")
+		lg.Printf("%s", y) //@rename("y", "y2"),rename("lg","log")
 	default:
-		fmt.Printf("%v", y) //@rename("y", "y3")
+		f2.Printf("%v", y) //@rename("y", "y3"),rename("f2","fmt2")
 	}
 }

internal/lsp/tests/tests.go

@@ -34,7 +34,7 @@ const (
 	ExpectedTypeDefinitionsCount   = 2
 	ExpectedHighlightsCount        = 2
 	ExpectedReferencesCount        = 4
-	ExpectedRenamesCount           = 8
+	ExpectedRenamesCount           = 11
 	ExpectedSymbolsCount           = 1
 	ExpectedSignaturesCount        = 20
 	ExpectedLinksCount             = 2