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mirror of https://github.com/golang/go synced 2024-11-18 11:34:45 -07:00

internal/lsp: check for file URIs on LSP requests

In general, we expect all URIs to be file:// scheme. Silently ignore
requests that come in for other schemes. (In the command-line client we
panic since we should never see anything else.)

The calling convention for beginFileRequest is odd; see the function
comment.

Fixes golang/go#33699.

Change-Id: Ie721e9a85478f3a12975f6528cfbd28cc7910be8
Reviewed-on: https://go-review.googlesource.com/c/tools/+/219483
Run-TryBot: Heschi Kreinick <heschi@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Rebecca Stambler <rstambler@golang.org>
This commit is contained in:
Heschi Kreinick 2020-02-13 13:46:49 -05:00
parent f7b8cc7bd0
commit 5916a50871
25 changed files with 131 additions and 224 deletions

View File

@ -293,6 +293,15 @@ func newConnection(app *Application) *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) ShowMessage(ctx context.Context, p *protocol.ShowMessageParams) error { return nil }
func (c *cmdClient) ShowMessageRequest(ctx context.Context, p *protocol.ShowMessageRequestParams) (*protocol.MessageActionItem, error) {
@ -373,7 +382,7 @@ func (c *cmdClient) PublishDiagnostics(ctx context.Context, p *protocol.PublishD
c.filesMu.Lock()
defer c.filesMu.Unlock()
file := c.getFile(ctx, p.URI.SpanURI())
file := c.getFile(ctx, fileURI(p.URI))
file.diagnostics = p.Diagnostics
return nil
}

View File

@ -109,7 +109,7 @@ func (d *definition) Run(ctx context.Context, args ...string) error {
if hover == nil {
return errors.Errorf("%v: not an identifier", from)
}
file = conn.AddFile(ctx, locs[0].URI.SpanURI())
file = conn.AddFile(ctx, fileURI(locs[0].URI))
if file.err != nil {
return errors.Errorf("%v: %v", from, file.err)
}

View File

@ -72,7 +72,7 @@ func (i *implementation) Run(ctx context.Context, args ...string) error {
var spans []string
for _, impl := range implementations {
f := conn.AddFile(ctx, impl.URI.SpanURI())
f := conn.AddFile(ctx, fileURI(impl.URI))
span, err := f.mapper.Span(impl)
if err != nil {
return err

View File

@ -74,7 +74,7 @@ func (t *imports) Run(ctx context.Context, args ...string) error {
continue
}
for _, c := range a.Edit.DocumentChanges {
if c.TextDocument.URI.SpanURI() == uri {
if fileURI(c.TextDocument.URI) == uri {
edits = append(edits, c.Edits...)
}
}

View File

@ -73,7 +73,7 @@ func (r *references) Run(ctx context.Context, args ...string) error {
}
var spans []string
for _, l := range locations {
f := conn.AddFile(ctx, l.URI.SpanURI())
f := conn.AddFile(ctx, fileURI(l.URI))
// convert location to span for user-friendly 1-indexed line
// and column numbers
span, err := f.mapper.Span(l)

View File

@ -81,7 +81,7 @@ func (r *rename) Run(ctx context.Context, args ...string) error {
var orderedURIs []string
edits := map[span.URI][]protocol.TextEdit{}
for _, c := range edit.DocumentChanges {
uri := c.TextDocument.URI.SpanURI()
uri := fileURI(c.TextDocument.URI)
edits[uri] = append(edits[uri], c.Edits...)
orderedURIs = append(orderedURIs, string(uri))
}

View File

@ -87,7 +87,7 @@ func (s *suggestedfix) Run(ctx context.Context, args ...string) error {
continue
}
for _, c := range a.Edit.DocumentChanges {
if c.TextDocument.URI.SpanURI() == uri {
if fileURI(c.TextDocument.URI) == uri {
edits = append(edits, c.Edits...)
}
}

View File

@ -20,19 +20,14 @@ import (
)
func (s *Server) codeAction(ctx context.Context, params *protocol.CodeActionParams) ([]protocol.CodeAction, error) {
uri := params.TextDocument.URI.SpanURI()
view, err := s.session.ViewOf(uri)
if err != nil {
return nil, err
}
snapshot := view.Snapshot()
fh, err := snapshot.GetFile(uri)
if err != nil {
snapshot, fh, ok, err := s.beginFileRequest(params.TextDocument.URI, source.UnknownKind)
if !ok {
return nil, err
}
uri := fh.Identity().URI
// Determine the supported actions for this file kind.
supportedCodeActions, ok := view.Options().SupportedCodeActions[fh.Identity().Kind]
supportedCodeActions, ok := snapshot.View().Options().SupportedCodeActions[fh.Identity().Kind]
if !ok {
return nil, fmt.Errorf("no supported code actions for %v file kind", fh.Identity().Kind)
}

View File

@ -5,7 +5,6 @@ import (
"golang.org/x/tools/internal/lsp/protocol"
"golang.org/x/tools/internal/lsp/source"
"golang.org/x/tools/internal/span"
errors "golang.org/x/xerrors"
)
@ -15,36 +14,27 @@ func (s *Server) executeCommand(ctx context.Context, params *protocol.ExecuteCom
if len(params.Arguments) == 0 || len(params.Arguments) > 1 {
return nil, errors.Errorf("expected one file URI for call to `go mod tidy`, got %v", params.Arguments)
}
// Confirm that this action is being taken on a go.mod file.
uri := span.URIFromURI(params.Arguments[0].(string))
view, err := s.session.ViewOf(uri)
if err != nil {
uri := protocol.DocumentURI(params.Arguments[0].(string))
snapshot, _, ok, err := s.beginFileRequest(uri, source.Mod)
if !ok {
return nil, err
}
snapshot := view.Snapshot()
fh, err := snapshot.GetFile(uri)
if err != nil {
return nil, err
}
if fh.Identity().Kind != source.Mod {
return nil, errors.Errorf("%s is not a mod file", uri)
}
// Run go.mod tidy on the view.
if _, err := source.InvokeGo(ctx, view.Folder().Filename(), snapshot.Config(ctx).Env, "mod", "tidy"); err != nil {
if _, err := source.InvokeGo(ctx, snapshot.View().Folder().Filename(), snapshot.Config(ctx).Env, "mod", "tidy"); err != nil {
return nil, err
}
case "upgrade.dependency":
if len(params.Arguments) < 2 {
return nil, errors.Errorf("expected one file URI and one dependency for call to `go get`, got %v", params.Arguments)
}
uri := span.URIFromURI(params.Arguments[0].(string))
view, err := s.session.ViewOf(uri)
if err != nil {
uri := protocol.DocumentURI(params.Arguments[0].(string))
snapshot, _, ok, err := s.beginFileRequest(uri, source.UnknownKind)
if !ok {
return nil, err
}
dep := params.Arguments[1].(string)
// Run "go get" on the dependency to upgrade it to the latest version.
if _, err := source.InvokeGo(ctx, view.Folder().Filename(), view.Snapshot().Config(ctx).Env, "get", dep); err != nil {
if _, err := source.InvokeGo(ctx, snapshot.View().Folder().Filename(), snapshot.Config(ctx).Env, "get", dep); err != nil {
return nil, err
}
}

View File

@ -16,14 +16,8 @@ import (
)
func (s *Server) completion(ctx context.Context, params *protocol.CompletionParams) (*protocol.CompletionList, error) {
uri := params.TextDocument.URI.SpanURI()
view, err := s.session.ViewOf(uri)
if err != nil {
return nil, err
}
snapshot := view.Snapshot()
fh, err := snapshot.GetFile(uri)
if err != nil {
snapshot, fh, ok, err := s.beginFileRequest(params.TextDocument.URI, source.UnknownKind)
if !ok {
return nil, err
}
var candidates []source.CompletionItem
@ -51,7 +45,7 @@ func (s *Server) completion(ctx context.Context, params *protocol.CompletionPara
// When using deep completions/fuzzy matching, report results as incomplete so
// client fetches updated completions after every key stroke.
options := view.Options()
options := snapshot.View().Options()
incompleteResults := options.DeepCompletion || options.Matcher == source.Fuzzy
items := toProtocolCompletionItems(candidates, rng, options)

View File

@ -12,19 +12,10 @@ import (
)
func (s *Server) definition(ctx context.Context, params *protocol.DefinitionParams) ([]protocol.Location, error) {
uri := params.TextDocument.URI.SpanURI()
view, err := s.session.ViewOf(uri)
if err != nil {
snapshot, fh, ok, err := s.beginFileRequest(params.TextDocument.URI, source.Go)
if !ok {
return nil, err
}
snapshot := view.Snapshot()
fh, err := snapshot.GetFile(uri)
if err != nil {
return nil, err
}
if fh.Identity().Kind != source.Go {
return nil, nil
}
ident, err := source.Identifier(ctx, snapshot, fh, params.Position)
if err != nil {
return nil, err
@ -42,19 +33,10 @@ func (s *Server) definition(ctx context.Context, params *protocol.DefinitionPara
}
func (s *Server) typeDefinition(ctx context.Context, params *protocol.TypeDefinitionParams) ([]protocol.Location, error) {
uri := params.TextDocument.URI.SpanURI()
view, err := s.session.ViewOf(uri)
if err != nil {
snapshot, fh, ok, err := s.beginFileRequest(params.TextDocument.URI, source.Go)
if !ok {
return nil, err
}
snapshot := view.Snapshot()
fh, err := snapshot.GetFile(uri)
if err != nil {
return nil, err
}
if fh.Identity().Kind != source.Go {
return nil, nil
}
ident, err := source.Identifier(ctx, snapshot, fh, params.Position)
if err != nil {
return nil, err

View File

@ -8,24 +8,12 @@ import (
)
func (s *Server) foldingRange(ctx context.Context, params *protocol.FoldingRangeParams) ([]protocol.FoldingRange, error) {
uri := params.TextDocument.URI.SpanURI()
view, err := s.session.ViewOf(uri)
if err != nil {
snapshot, fh, ok, err := s.beginFileRequest(params.TextDocument.URI, source.Go)
if !ok {
return nil, err
}
snapshot := view.Snapshot()
fh, err := snapshot.GetFile(uri)
if err != nil {
return nil, err
}
var ranges []*source.FoldingRangeInfo
switch fh.Identity().Kind {
case source.Go:
ranges, err = source.FoldingRange(ctx, snapshot, fh, view.Options().LineFoldingOnly)
case source.Mod:
ranges = nil
}
ranges, err := source.FoldingRange(ctx, snapshot, fh, snapshot.View().Options().LineFoldingOnly)
if err != nil {
return nil, err
}

View File

@ -12,24 +12,11 @@ import (
)
func (s *Server) formatting(ctx context.Context, params *protocol.DocumentFormattingParams) ([]protocol.TextEdit, error) {
uri := params.TextDocument.URI.SpanURI()
view, err := s.session.ViewOf(uri)
if err != nil {
snapshot, fh, ok, err := s.beginFileRequest(params.TextDocument.URI, source.Go)
if !ok {
return nil, err
}
snapshot := view.Snapshot()
fh, err := snapshot.GetFile(uri)
if err != nil {
return nil, err
}
var edits []protocol.TextEdit
switch fh.Identity().Kind {
case source.Go:
edits, err = source.Format(ctx, snapshot, fh)
case source.Mod:
return nil, nil
}
edits, err := source.Format(ctx, snapshot, fh)
if err != nil {
return nil, err
}

View File

@ -234,6 +234,32 @@ func (s *Server) fetchConfig(ctx context.Context, name string, folder span.URI,
return nil
}
// beginFileRequest checks preconditions for a file-oriented request and routes
// it to a snapshot.
// We don't want to return errors for benign conditions like wrong file type,
// so callers should do if !ok { return err } rather than if err != nil.
func (s *Server) beginFileRequest(pURI protocol.DocumentURI, expectKind source.FileKind) (source.Snapshot, source.FileHandle, bool, error) {
uri := pURI.SpanURI()
if !uri.IsFile() {
// Not a file URI. Stop processing the request, but don't return an error.
return nil, nil, false, nil
}
view, err := s.session.ViewOf(uri)
if err != nil {
return nil, nil, false, err
}
snapshot := view.Snapshot()
fh, err := snapshot.GetFile(uri)
if err != nil {
return nil, nil, false, err
}
if expectKind != source.UnknownKind && fh.Identity().Kind != expectKind {
// Wrong kind of file. Nothing to do.
return nil, nil, false, nil
}
return snapshot, fh, true, nil
}
func (s *Server) shutdown(ctx context.Context) error {
s.stateMu.Lock()
defer s.stateMu.Unlock()

View File

@ -14,26 +14,13 @@ import (
)
func (s *Server) documentHighlight(ctx context.Context, params *protocol.DocumentHighlightParams) ([]protocol.DocumentHighlight, error) {
uri := params.TextDocument.URI.SpanURI()
view, err := s.session.ViewOf(uri)
if err != nil {
snapshot, fh, ok, err := s.beginFileRequest(params.TextDocument.URI, source.Go)
if !ok {
return nil, err
}
snapshot := view.Snapshot()
fh, err := snapshot.GetFile(uri)
rngs, err := source.Highlight(ctx, snapshot, fh, params.Position)
if err != nil {
return nil, err
}
var rngs []protocol.Range
switch fh.Identity().Kind {
case source.Go:
rngs, err = source.Highlight(ctx, snapshot, fh, params.Position)
case source.Mod:
return nil, nil
}
if err != nil {
log.Error(ctx, "no highlight", err, telemetry.URI.Of(uri))
log.Error(ctx, "no highlight", err, telemetry.URI.Of(params.TextDocument.URI))
}
return toProtocolHighlight(rngs), nil
}

View File

@ -12,19 +12,10 @@ import (
)
func (s *Server) hover(ctx context.Context, params *protocol.HoverParams) (*protocol.Hover, error) {
uri := params.TextDocument.URI.SpanURI()
view, err := s.session.ViewOf(uri)
if err != nil {
snapshot, fh, ok, err := s.beginFileRequest(params.TextDocument.URI, source.Go)
if !ok {
return nil, err
}
snapshot := view.Snapshot()
fh, err := snapshot.GetFile(uri)
if err != nil {
return nil, err
}
if fh.Identity().Kind != source.Go {
return nil, nil
}
ident, err := source.Identifier(ctx, snapshot, fh, params.Position)
if err != nil {
return nil, nil
@ -37,13 +28,13 @@ func (s *Server) hover(ctx context.Context, params *protocol.HoverParams) (*prot
if err != nil {
return nil, err
}
hover, err := source.FormatHover(h, view.Options())
hover, err := source.FormatHover(h, snapshot.View().Options())
if err != nil {
return nil, err
}
return &protocol.Hover{
Contents: protocol.MarkupContent{
Kind: view.Options().PreferredContentFormat,
Kind: snapshot.View().Options().PreferredContentFormat,
Value: hover,
},
Range: rng,

View File

@ -12,18 +12,9 @@ import (
)
func (s *Server) implementation(ctx context.Context, params *protocol.ImplementationParams) ([]protocol.Location, error) {
uri := params.TextDocument.URI.SpanURI()
view, err := s.session.ViewOf(uri)
if err != nil {
snapshot, fh, ok, err := s.beginFileRequest(params.TextDocument.URI, source.Go)
if !ok {
return nil, err
}
snapshot := view.Snapshot()
fh, err := snapshot.GetFile(uri)
if err != nil {
return nil, err
}
if fh.Identity().Kind != source.Go {
return nil, nil
}
return source.Implementation(ctx, snapshot, fh, params.Position)
}

View File

@ -21,19 +21,12 @@ import (
)
func (s *Server) documentLink(ctx context.Context, params *protocol.DocumentLinkParams) ([]protocol.DocumentLink, error) {
uri := params.TextDocument.URI.SpanURI()
view, err := s.session.ViewOf(uri)
if err != nil {
return nil, err
}
fh, err := view.Snapshot().GetFile(uri)
if err != nil {
return nil, err
}
// TODO(golang/go#36501): Support document links for go.mod files.
if fh.Identity().Kind == source.Mod {
return nil, nil
snapshot, fh, ok, err := s.beginFileRequest(params.TextDocument.URI, source.Go)
if !ok {
return nil, err
}
view := snapshot.View()
file, _, m, _, err := view.Session().Cache().ParseGoHandle(fh, source.ParseFull).Parse(ctx)
if err != nil {
return nil, err

View File

@ -12,22 +12,11 @@ import (
)
func (s *Server) references(ctx context.Context, params *protocol.ReferenceParams) ([]protocol.Location, error) {
uri := params.TextDocument.URI.SpanURI()
view, err := s.session.ViewOf(uri)
if err != nil {
snapshot, fh, ok, err := s.beginFileRequest(params.TextDocument.URI, source.Go)
if !ok {
return nil, err
}
snapshot := view.Snapshot()
fh, err := snapshot.GetFile(uri)
if err != nil {
return nil, err
}
// Find all references to the identifier at the position.
if fh.Identity().Kind != source.Go {
return nil, nil
}
references, err := source.References(ctx, view.Snapshot(), fh, params.Position, params.Context.IncludeDeclaration)
references, err := source.References(ctx, snapshot, fh, params.Position, params.Context.IncludeDeclaration)
if err != nil {
return nil, err
}

View File

@ -12,20 +12,10 @@ import (
)
func (s *Server) rename(ctx context.Context, params *protocol.RenameParams) (*protocol.WorkspaceEdit, error) {
uri := params.TextDocument.URI.SpanURI()
view, err := s.session.ViewOf(uri)
if err != nil {
snapshot, fh, ok, err := s.beginFileRequest(params.TextDocument.URI, source.Go)
if !ok {
return nil, err
}
snapshot := view.Snapshot()
fh, err := snapshot.GetFile(uri)
if err != nil {
return nil, err
}
if fh.Identity().Kind != source.Go {
return nil, nil
}
edits, err := source.Rename(ctx, snapshot, fh, params.Position, params.NewName)
if err != nil {
return nil, err
@ -45,20 +35,10 @@ func (s *Server) rename(ctx context.Context, params *protocol.RenameParams) (*pr
}
func (s *Server) prepareRename(ctx context.Context, params *protocol.PrepareRenameParams) (*protocol.Range, error) {
uri := params.TextDocument.URI.SpanURI()
view, err := s.session.ViewOf(uri)
if err != nil {
snapshot, fh, ok, err := s.beginFileRequest(params.TextDocument.URI, source.Go)
if !ok {
return nil, err
}
snapshot := view.Snapshot()
fh, err := snapshot.GetFile(uri)
if err != nil {
return nil, err
}
if fh.Identity().Kind != source.Go {
return nil, nil
}
// Do not return errors here, as it adds clutter.
// Returning a nil result means there is not a valid rename.
item, err := source.PrepareRename(ctx, snapshot, fh, params.Position)

View File

@ -95,17 +95,17 @@ func (s *Server) nonstandardRequest(ctx context.Context, method string, params i
paramMap := params.(map[string]interface{})
if method == "gopls/diagnoseFiles" {
for _, file := range paramMap["files"].([]interface{}) {
uri := span.URIFromURI(file.(string))
view, err := s.session.ViewOf(uri)
if err != nil {
snapshot, fh, ok, err := s.beginFileRequest(protocol.DocumentURI(file.(string)), source.UnknownKind)
if !ok {
return nil, err
}
fileID, diagnostics, err := source.FileDiagnostics(ctx, view.Snapshot(), uri)
fileID, diagnostics, err := source.FileDiagnostics(ctx, snapshot, fh.Identity().URI)
if err != nil {
return nil, err
}
if err := s.client.PublishDiagnostics(ctx, &protocol.PublishDiagnosticsParams{
URI: protocol.URIFromSpanURI(uri),
URI: protocol.URIFromSpanURI(fh.Identity().URI),
Diagnostics: toProtocolDiagnostics(diagnostics),
Version: fileID.Version,
}); err != nil {

View File

@ -14,19 +14,10 @@ import (
)
func (s *Server) signatureHelp(ctx context.Context, params *protocol.SignatureHelpParams) (*protocol.SignatureHelp, error) {
uri := params.TextDocument.URI.SpanURI()
view, err := s.session.ViewOf(uri)
if err != nil {
snapshot, fh, ok, err := s.beginFileRequest(params.TextDocument.URI, source.Go)
if !ok {
return nil, err
}
snapshot := view.Snapshot()
fh, err := snapshot.GetFile(uri)
if err != nil {
return nil, err
}
if fh.Identity().Kind != source.Go {
return nil, nil
}
info, activeParameter, err := source.SignatureHelp(ctx, snapshot, fh, params.Position)
if err != nil {
log.Print(ctx, "no signature help", tag.Of("At", params.Position), tag.Of("Failure", err))

View File

@ -18,26 +18,13 @@ func (s *Server) documentSymbol(ctx context.Context, params *protocol.DocumentSy
ctx, done := trace.StartSpan(ctx, "lsp.Server.documentSymbol")
defer done()
uri := params.TextDocument.URI.SpanURI()
view, err := s.session.ViewOf(uri)
if err != nil {
return nil, err
snapshot, fh, ok, err := s.beginFileRequest(params.TextDocument.URI, source.Go)
if !ok {
return []protocol.DocumentSymbol{}, err
}
snapshot := view.Snapshot()
fh, err := snapshot.GetFile(uri)
symbols, err := source.DocumentSymbols(ctx, snapshot, fh)
if err != nil {
return nil, err
}
var symbols []protocol.DocumentSymbol
switch fh.Identity().Kind {
case source.Go:
symbols, err = source.DocumentSymbols(ctx, snapshot, fh)
case source.Mod:
return []protocol.DocumentSymbol{}, nil
}
if err != nil {
log.Error(ctx, "DocumentSymbols failed", err, telemetry.URI.Of(uri))
log.Error(ctx, "DocumentSymbols failed", err, telemetry.URI.Of(fh.Identity().URI))
return []protocol.DocumentSymbol{}, nil
}
return symbols, nil

View File

@ -17,9 +17,14 @@ import (
)
func (s *Server) didOpen(ctx context.Context, params *protocol.DidOpenTextDocumentParams) error {
uri := params.TextDocument.URI.SpanURI()
if !uri.IsFile() {
return nil
}
_, err := s.didModifyFiles(ctx, []source.FileModification{
{
URI: params.TextDocument.URI.SpanURI(),
URI: uri,
Action: source.Open,
Version: params.TextDocument.Version,
Text: []byte(params.TextDocument.Text),
@ -31,6 +36,10 @@ func (s *Server) didOpen(ctx context.Context, params *protocol.DidOpenTextDocume
func (s *Server) didChange(ctx context.Context, params *protocol.DidChangeTextDocumentParams) error {
uri := params.TextDocument.URI.SpanURI()
if !uri.IsFile() {
return nil
}
text, err := s.changedText(ctx, uri, params.ContentChanges)
if err != nil {
return err
@ -65,8 +74,12 @@ func (s *Server) didChange(ctx context.Context, params *protocol.DidChangeTextDo
func (s *Server) didChangeWatchedFiles(ctx context.Context, params *protocol.DidChangeWatchedFilesParams) error {
var modifications []source.FileModification
for _, change := range params.Changes {
uri := change.URI.SpanURI()
if !uri.IsFile() {
continue
}
modifications = append(modifications, source.FileModification{
URI: change.URI.SpanURI(),
URI: uri,
Action: changeTypeToFileAction(change.Type),
OnDisk: true,
})
@ -76,8 +89,13 @@ func (s *Server) didChangeWatchedFiles(ctx context.Context, params *protocol.Did
}
func (s *Server) didSave(ctx context.Context, params *protocol.DidSaveTextDocumentParams) error {
uri := params.TextDocument.URI.SpanURI()
if !uri.IsFile() {
return nil
}
c := source.FileModification{
URI: params.TextDocument.URI.SpanURI(),
URI: uri,
Action: source.Save,
Version: params.TextDocument.Version,
}
@ -89,9 +107,14 @@ func (s *Server) didSave(ctx context.Context, params *protocol.DidSaveTextDocume
}
func (s *Server) didClose(ctx context.Context, params *protocol.DidCloseTextDocumentParams) error {
uri := params.TextDocument.URI.SpanURI()
if !uri.IsFile() {
return nil
}
_, err := s.didModifyFiles(ctx, []source.FileModification{
{
URI: params.TextDocument.URI.SpanURI(),
URI: uri,
Action: source.Close,
Version: -1,
Text: nil,

View File

@ -20,6 +20,10 @@ const fileScheme = "file"
// URI represents the full URI for a file.
type URI string
func (uri URI) IsFile() bool {
return strings.HasPrefix(string(uri), "file://")
}
// Filename returns the file path for the given URI.
// It is an error to call this on a URI that is not a valid filename.
func (uri URI) Filename() string {