| package lsp |
| |
| import ( |
| "context" |
| |
| "golang.org/x/tools/internal/lsp/protocol" |
| "golang.org/x/tools/internal/lsp/source" |
| ) |
| |
| // formatRange formats a document with a given range. |
| func formatRange(ctx context.Context, v source.View, uri protocol.DocumentURI, rng *protocol.Range) ([]protocol.TextEdit, error) { |
| sourceURI, err := fromProtocolURI(uri) |
| if err != nil { |
| return nil, err |
| } |
| f, err := v.GetFile(ctx, sourceURI) |
| if err != nil { |
| return nil, err |
| } |
| tok := f.GetToken() |
| var r source.Range |
| if rng == nil { |
| r.Start = tok.Pos(0) |
| r.End = tok.Pos(tok.Size()) |
| } else { |
| r = fromProtocolRange(tok, *rng) |
| } |
| edits, err := source.Format(ctx, f, r) |
| if err != nil { |
| return nil, err |
| } |
| return toProtocolEdits(f, edits), nil |
| } |
| |
| func toProtocolEdits(f source.File, edits []source.TextEdit) []protocol.TextEdit { |
| if edits == nil { |
| return nil |
| } |
| tok := f.GetToken() |
| content := f.GetContent() |
| // When a file ends with an empty line, the newline character is counted |
| // as part of the previous line. This causes the formatter to insert |
| // another unnecessary newline on each formatting. We handle this case by |
| // checking if the file already ends with a newline character. |
| hasExtraNewline := content[len(content)-1] == '\n' |
| result := make([]protocol.TextEdit, len(edits)) |
| for i, edit := range edits { |
| rng := toProtocolRange(tok, edit.Range) |
| // If the edit ends at the end of the file, add the extra line. |
| if hasExtraNewline && tok.Offset(edit.Range.End) == len(content) { |
| rng.End.Line++ |
| rng.End.Character = 0 |
| } |
| result[i] = protocol.TextEdit{ |
| Range: rng, |
| NewText: edit.NewText, |
| } |
| } |
| return result |
| } |