blob: 1df62d001baf0dd3a49badcd41e81db7c60944fe [file] [log] [blame]
// Copyright 2019 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
package source
import (
"bytes"
"context"
"go/ast"
"go/format"
"go/token"
"go/types"
"regexp"
"golang.org/x/tools/go/types/typeutil"
"golang.org/x/tools/internal/lsp/diff"
"golang.org/x/tools/internal/lsp/protocol"
"golang.org/x/tools/internal/span"
"golang.org/x/tools/internal/telemetry/trace"
"golang.org/x/tools/refactor/satisfy"
errors "golang.org/x/xerrors"
)
type renamer struct {
ctx context.Context
fset *token.FileSet
refs []*ReferenceInfo
objsToUpdate map[types.Object]bool
hadConflicts bool
errors string
from, to string
satisfyConstraints map[satisfy.Constraint]bool
packages map[*types.Package]Package // may include additional packages that are a rdep of pkg
msets typeutil.MethodSetCache
changeMethods bool
}
type PrepareItem struct {
Range protocol.Range
Text string
}
func (i *IdentifierInfo) PrepareRename(ctx context.Context) (*PrepareItem, error) {
ctx, done := trace.StartSpan(ctx, "source.PrepareRename")
defer done()
// TODO(rstambler): We should handle this in a better way.
// If the object declaration is nil, assume it is an import spec.
if i.Declaration.obj == nil {
// Find the corresponding package name for this import spec
// and rename that instead.
ident, err := i.getPkgName(ctx)
if err != nil {
return nil, err
}
rng, err := ident.mappedRange.Range()
if err != nil {
return nil, err
}
// We're not really renaming the import path.
rng.End = rng.Start
return &PrepareItem{
Range: rng,
Text: ident.Name,
}, nil
}
// Do not rename builtin identifiers.
if i.Declaration.obj.Parent() == types.Universe {
return nil, errors.Errorf("cannot rename builtin %q", i.Name)
}
rng, err := i.mappedRange.Range()
if err != nil {
return nil, err
}
return &PrepareItem{
Range: rng,
Text: i.Name,
}, nil
}
// Rename returns a map of TextEdits for each file modified when renaming a given identifier within a package.
func (i *IdentifierInfo) Rename(ctx context.Context, newName string) (map[span.URI][]protocol.TextEdit, error) {
ctx, done := trace.StartSpan(ctx, "source.Rename")
defer done()
// TODO(rstambler): We should handle this in a better way.
// If the object declaration is nil, assume it is an import spec.
if i.Declaration.obj == nil {
// Find the corresponding package name for this import spec
// and rename that instead.
ident, err := i.getPkgName(ctx)
if err != nil {
return nil, err
}
return ident.Rename(ctx, newName)
}
if i.Name == newName {
return nil, errors.Errorf("old and new names are the same: %s", newName)
}
if !isValidIdentifier(newName) {
return nil, errors.Errorf("invalid identifier to rename: %q", i.Name)
}
// Do not rename builtin identifiers.
if i.Declaration.obj.Parent() == types.Universe {
return nil, errors.Errorf("cannot rename builtin %q", i.Name)
}
if i.pkg == nil || i.pkg.IsIllTyped() {
return nil, errors.Errorf("package for %s is ill typed", i.File.File().Identity().URI)
}
// Do not rename identifiers declared in another package.
if i.pkg.GetTypes() != i.Declaration.obj.Pkg() {
return nil, errors.Errorf("failed to rename because %q is declared in package %q", i.Name, i.Declaration.obj.Pkg().Name())
}
refs, err := i.References(ctx)
if err != nil {
return nil, err
}
r := renamer{
ctx: ctx,
fset: i.Snapshot.View().Session().Cache().FileSet(),
refs: refs,
objsToUpdate: make(map[types.Object]bool),
from: i.Name,
to: newName,
packages: make(map[*types.Package]Package),
}
for _, from := range refs {
r.packages[from.pkg.GetTypes()] = from.pkg
}
// Check that the renaming of the identifier is ok.
for _, ref := range refs {
r.check(ref.obj)
if r.hadConflicts { // one error is enough.
break
}
}
if r.hadConflicts {
return nil, errors.Errorf(r.errors)
}
changes, err := r.update()
if err != nil {
return nil, err
}
result := make(map[span.URI][]protocol.TextEdit)
for uri, edits := range changes {
// These edits should really be associated with FileHandles for maximal correctness.
// For now, this is good enough.
f, err := i.Snapshot.View().GetFile(ctx, uri)
if err != nil {
return nil, err
}
fh := i.Snapshot.Handle(ctx, f)
data, _, err := fh.Read(ctx)
if err != nil {
return nil, err
}
converter := span.NewContentConverter(uri.Filename(), data)
m := &protocol.ColumnMapper{
URI: uri,
Converter: converter,
Content: data,
}
// Sort the edits first.
diff.SortTextEdits(edits)
protocolEdits, err := ToProtocolEdits(m, edits)
if err != nil {
return nil, err
}
result[uri] = protocolEdits
}
return result, nil
}
// getPkgName gets the pkg name associated with an identifier representing
// the import path in an import spec.
func (i *IdentifierInfo) getPkgName(ctx context.Context) (*IdentifierInfo, error) {
ph, err := i.pkg.File(i.URI())
if err != nil {
return nil, err
}
file, _, _, err := ph.Cached()
if err != nil {
return nil, err
}
var namePos token.Pos
for _, spec := range file.Imports {
if spec.Path.Pos() == i.spanRange.Start {
namePos = spec.Pos()
break
}
}
if !namePos.IsValid() {
return nil, errors.Errorf("import spec not found for %q", i.Name)
}
// Look for the object defined at NamePos.
for _, obj := range i.pkg.GetTypesInfo().Defs {
pkgName, ok := obj.(*types.PkgName)
if ok && pkgName.Pos() == namePos {
return getPkgNameIdentifier(ctx, i, pkgName)
}
}
for _, obj := range i.pkg.GetTypesInfo().Implicits {
pkgName, ok := obj.(*types.PkgName)
if ok && pkgName.Pos() == namePos {
return getPkgNameIdentifier(ctx, i, pkgName)
}
}
return nil, errors.Errorf("no package name for %q", i.Name)
}
// getPkgNameIdentifier returns an IdentifierInfo representing pkgName.
// pkgName must be in the same package and file as ident.
func getPkgNameIdentifier(ctx context.Context, ident *IdentifierInfo, pkgName *types.PkgName) (*IdentifierInfo, error) {
decl := Declaration{
obj: pkgName,
wasImplicit: true,
}
var err error
if decl.mappedRange, err = objToMappedRange(ident.Snapshot.View(), ident.pkg, decl.obj); err != nil {
return nil, err
}
if decl.node, err = objToNode(ident.Snapshot.View(), ident.pkg, decl.obj); err != nil {
return nil, err
}
return &IdentifierInfo{
Snapshot: ident.Snapshot,
Name: pkgName.Name(),
mappedRange: decl.mappedRange,
File: ident.File,
Declaration: decl,
pkg: ident.pkg,
qf: ident.qf,
}, nil
}
// Rename all references to the identifier.
func (r *renamer) update() (map[span.URI][]diff.TextEdit, error) {
result := make(map[span.URI][]diff.TextEdit)
seen := make(map[span.Span]bool)
docRegexp, err := regexp.Compile(`\b` + r.from + `\b`)
if err != nil {
return nil, err
}
for _, ref := range r.refs {
refSpan, err := ref.spanRange.Span()
if err != nil {
return nil, err
}
if seen[refSpan] {
continue
}
seen[refSpan] = true
// 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 := diff.TextEdit{
Span: refSpan,
NewText: r.to,
}
result[refSpan.URI()] = append(result[refSpan.URI()], edit)
if !ref.isDeclaration || ref.ident == nil { // uses do not have doc comments to update.
continue
}
doc := r.docComment(ref.pkg, ref.ident)
if doc == nil {
continue
}
// 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]))
spn, err := rng.Span()
if err != nil {
return nil, err
}
result[spn.URI()] = append(result[spn.URI()], diff.TextEdit{
Span: spn,
NewText: r.to,
})
}
}
}
return result, nil
}
// docComment returns the doc for an identifier.
func (r *renamer) docComment(pkg Package, id *ast.Ident) *ast.CommentGroup {
_, nodes, _ := pathEnclosingInterval(r.ctx, r.fset, pkg, id.Pos(), id.End())
for _, node := range nodes {
switch decl := node.(type) {
case *ast.FuncDecl:
return decl.Doc
case *ast.Field:
return decl.Doc
case *ast.GenDecl:
return decl.Doc
// For {Type,Value}Spec, if the doc on the spec is absent,
// search for the enclosing GenDecl
case *ast.TypeSpec:
if decl.Doc != nil {
return decl.Doc
}
case *ast.ValueSpec:
if decl.Doc != nil {
return decl.Doc
}
case *ast.Ident:
default:
return nil
}
}
return nil
}
// updatePkgName returns the updates to rename a pkgName in the import spec
func (r *renamer) updatePkgName(pkgName *types.PkgName) (*diff.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, errors.Errorf("no path enclosing interval for %s", pkgName.Name())
}
spec, ok := path[1].(*ast.ImportSpec)
if !ok {
return nil, errors.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 &diff.TextEdit{
Span: spn,
NewText: newText,
}, nil
}