blob: f576d696c1859c4dae9da3bd1f508cf17973f79e [file] [log] [blame]
// Copyright 2022 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 work
import (
"bytes"
"context"
"fmt"
"golang.org/x/mod/modfile"
"golang.org/x/tools/gopls/internal/lsp/protocol"
"golang.org/x/tools/gopls/internal/lsp/source"
"golang.org/x/tools/internal/event"
)
func Hover(ctx context.Context, snapshot source.Snapshot, fh source.FileHandle, position protocol.Position) (*protocol.Hover, error) {
// We only provide hover information for the view's go.work file.
if fh.URI() != snapshot.WorkFile() {
return nil, nil
}
ctx, done := event.Start(ctx, "work.Hover")
defer done()
// Get the position of the cursor.
pw, err := snapshot.ParseWork(ctx, fh)
if err != nil {
return nil, fmt.Errorf("getting go.work file handle: %w", err)
}
offset, err := pw.Mapper.PositionOffset(position)
if err != nil {
return nil, fmt.Errorf("computing cursor offset: %w", err)
}
// Confirm that the cursor is inside a use statement, and then find
// the position of the use statement's directory path.
use, pathStart, pathEnd := usePath(pw, offset)
// The cursor position is not on a use statement.
if use == nil {
return nil, nil
}
// Get the mod file denoted by the use.
modfh, err := snapshot.ReadFile(ctx, modFileURI(pw, use))
if err != nil {
return nil, fmt.Errorf("getting modfile handle: %w", err)
}
pm, err := snapshot.ParseMod(ctx, modfh)
if err != nil {
return nil, fmt.Errorf("getting modfile handle: %w", err)
}
mod := pm.File.Module.Mod
// Get the range to highlight for the hover.
rng, err := pw.Mapper.OffsetRange(pathStart, pathEnd)
if err != nil {
return nil, err
}
options := snapshot.View().Options()
return &protocol.Hover{
Contents: protocol.MarkupContent{
Kind: options.PreferredContentFormat,
Value: mod.Path,
},
Range: rng,
}, nil
}
func usePath(pw *source.ParsedWorkFile, offset int) (use *modfile.Use, pathStart, pathEnd int) {
for _, u := range pw.File.Use {
path := []byte(u.Path)
s, e := u.Syntax.Start.Byte, u.Syntax.End.Byte
i := bytes.Index(pw.Mapper.Content[s:e], path)
if i == -1 {
// This should not happen.
continue
}
// Shift the start position to the location of the
// module directory within the use statement.
pathStart, pathEnd = s+i, s+i+len(path)
if pathStart <= offset && offset <= pathEnd {
return u, pathStart, pathEnd
}
}
return nil, 0, 0
}