Allow using pointer receivers, and use struct pointers for input parameters

bootstrap/bootstrap.go

@@ -32,6 +32,7 @@ type Generator struct {
  OmitEmpty bool
  DisallowUnknownFields bool
  SkipMemberNameUnescaping bool
+ PtrReceivers bool
 
  OutName string
  BuildTags string
@@ -69,15 +70,19 @@ func (g *Generator) writeStub() error {
  fmt.Fprintln(f, ")")
  }
 
+ inPtrPrefix := ""
+ if g.PtrReceivers {
+ inPtrPrefix = "*"
+ }
  sort.Strings(g.Types)
  for _, t := range g.Types {
  fmt.Fprintln(f)
  if !g.NoStdMarshalers {
- fmt.Fprintln(f, "func (", t, ") MarshalJSON() ([]byte, error) { return nil, nil }")
+ fmt.Fprintln(f, "func (", inPtrPrefix, t, ") MarshalJSON() ([]byte, error) { return nil, nil }")
  fmt.Fprintln(f, "func (*", t, ") UnmarshalJSON([]byte) error { return nil }")
  }
 
- fmt.Fprintln(f, "func (", t, ") MarshalEasyJSON(w *jwriter.Writer) {}")
+ fmt.Fprintln(f, "func (", inPtrPrefix, t, ") MarshalEasyJSON(w *jwriter.Writer) {}")
  fmt.Fprintln(f, "func (*", t, ") UnmarshalEasyJSON(l *jlexer.Lexer) {}")
  fmt.Fprintln(f)
  fmt.Fprintln(f, "type EasyJSON_exporter_"+t+" *"+t)
@@ -137,6 +142,9 @@ func (g *Generator) writeMain() (path string, err error) {
  if g.SkipMemberNameUnescaping {
  fmt.Fprintln(f, " g.SkipMemberNameUnescaping()")
  }
+ if g.PtrReceivers {
+ fmt.Fprintln(f, " g.PtrReceivers()")
+ }
 
  sort.Strings(g.Types)
  for _, v := range g.Types {

easyjson/main.go

@@ -31,6 +31,7 @@ var specifiedName = flag.String("output_filename", "", "specify the filename of
 var processPkg = flag.Bool("pkg", false, "process the whole package instead of just the given file")
 var disallowUnknownFields = flag.Bool("disallow_unknown_fields", false, "return error if any unknown field in json appeared")
 var skipMemberNameUnescaping = flag.Bool("disable_members_unescape", false, "don't perform unescaping of member names to improve performance")
+var ptrReceivers = flag.Bool("ptr_receivers", false, "use pointer receivers for all generated marshaling methods")
 
 func generate(fname string) (err error) {
  fInfo, err := os.Stat(fname)
@@ -85,6 +86,7 @@ func generate(fname string) (err error) {
  StubsOnly: *stubs,
  NoFormat: *noformat,
  SimpleBytes: *simpleBytes,
+ PtrReceivers: *ptrReceivers,
  }
 
  if err := g.Run(); err != nil {

gen/encoder.go

@@ -203,7 +203,7 @@ func (g *Generator) genTypeEncoderNoCheck(t reflect.Type, in string, tags fieldT
  enc := g.getEncoderName(t)
  g.addType(t)
 
- fmt.Fprintln(g.out, ws+enc+"(out, "+in+")")
+ fmt.Fprintln(g.out, ws+enc+"(out, &"+in+")")
 
  case reflect.Ptr:
  if !assumeNonEmpty {
@@ -406,7 +406,7 @@ func (g *Generator) genStructEncoder(t reflect.Type) error {
  fname := g.getEncoderName(t)
  typ := g.getType(t)
 
- fmt.Fprintln(g.out, "func "+fname+"(out *jwriter.Writer, in "+typ+") {")
+ fmt.Fprintln(g.out, "func "+fname+"(out *jwriter.Writer, in *"+typ+") {")
  fmt.Fprintln(g.out, " out.RawByte('{')")
  fmt.Fprintln(g.out, " first := true")
  fmt.Fprintln(g.out, " _ = first")
@@ -449,18 +449,27 @@ func (g *Generator) genStructMarshaler(t reflect.Type) error {
  fname := g.getEncoderName(t)
  typ := g.getType(t)
 
+ ptrPrefix := ""
+ addrOfPrefix := ""
+ if t.Kind() == reflect.Struct {
+ if g.ptrReceivers {
+ ptrPrefix = "*"
+ } else {
+ addrOfPrefix = "&"
+ }
+ }
  if !g.noStdMarshalers {
  fmt.Fprintln(g.out, "// MarshalJSON supports json.Marshaler interface")
- fmt.Fprintln(g.out, "func (v "+typ+") MarshalJSON() ([]byte, error) {")
+ fmt.Fprintln(g.out, "func (v "+ptrPrefix+typ+") MarshalJSON() ([]byte, error) {")
  fmt.Fprintln(g.out, " w := jwriter.Writer{}")
- fmt.Fprintln(g.out, " "+fname+"(&w, v)")
+ fmt.Fprintln(g.out, " "+fname+"(&w, "+addrOfPrefix+"v)")
  fmt.Fprintln(g.out, " return w.Buffer.BuildBytes(), w.Error")
  fmt.Fprintln(g.out, "}")
  }
 
  fmt.Fprintln(g.out, "// MarshalEasyJSON supports easyjson.Marshaler interface")
- fmt.Fprintln(g.out, "func (v "+typ+") MarshalEasyJSON(w *jwriter.Writer) {")
- fmt.Fprintln(g.out, " "+fname+"(w, v)")
+ fmt.Fprintln(g.out, "func (v "+ptrPrefix+typ+") MarshalEasyJSON(w *jwriter.Writer) {")
+ fmt.Fprintln(g.out, " "+fname+"(w, "+addrOfPrefix+"v)")
  fmt.Fprintln(g.out, "}")
 
  return nil

gen/generator.go

@@ -39,6 +39,7 @@ type Generator struct {
  fieldNamer FieldNamer
  simpleBytes bool
  skipMemberNameUnescaping bool
+ ptrReceivers bool
 
  // package path to local alias map for tracking imports
  imports map[string]string
@@ -123,6 +124,11 @@ func (g *Generator) SkipMemberNameUnescaping() {
  g.skipMemberNameUnescaping = true
 }
 
+// PtrReceivers instructs to use pointer receivers for marshaling methods of structs.
+func (g *Generator) PtrReceivers() {
+ g.ptrReceivers = true
+}
+
 // OmitEmpty triggers `json=",omitempty"` behaviour by default.
 func (g *Generator) OmitEmpty() {
  g.omitEmpty = true