--- /dev/null
+package mod
+
+import (
+ "context"
+
+ "golang.org/x/tools/internal/event"
+ "golang.org/x/tools/internal/lsp/protocol"
+ "golang.org/x/tools/internal/lsp/source"
+)
+
+func Format(ctx context.Context, snapshot source.Snapshot, fh source.FileHandle) ([]protocol.TextEdit, error) {
+ ctx, done := event.Start(ctx, "mod.Format")
+ defer done()
+
+ pm, err := snapshot.ParseMod(ctx, fh)
+ if err != nil {
+ return nil, err
+ }
+ formatted, err := pm.File.Format()
+ if err != nil {
+ return nil, err
+ }
+ // Calculate the edits to be made due to the change.
+ diff := snapshot.View().Options().ComputeEdits(fh.URI(), string(pm.Mapper.Content), string(formatted))
+ return source.ToProtocolEdits(pm.Mapper, diff)
+}