diff options
Diffstat (limited to 'vendor/github.com/mailru/easyjson/gen/decoder.go')
| -rw-r--r-- | vendor/github.com/mailru/easyjson/gen/decoder.go | 489 |
1 files changed, 489 insertions, 0 deletions
diff --git a/vendor/github.com/mailru/easyjson/gen/decoder.go b/vendor/github.com/mailru/easyjson/gen/decoder.go new file mode 100644 index 000000000..021933ac8 --- /dev/null +++ b/vendor/github.com/mailru/easyjson/gen/decoder.go @@ -0,0 +1,489 @@ +package gen + +import ( + "encoding" + "encoding/json" + "fmt" + "reflect" + "strings" + "unicode" + + "github.com/mailru/easyjson" +) + +// Target this byte size for initial slice allocation to reduce garbage collection. +const minSliceBytes = 64 + +func (g *Generator) getDecoderName(t reflect.Type) string { + return g.functionName("decode", t) +} + +var primitiveDecoders = map[reflect.Kind]string{ + reflect.String: "in.String()", + reflect.Bool: "in.Bool()", + reflect.Int: "in.Int()", + reflect.Int8: "in.Int8()", + reflect.Int16: "in.Int16()", + reflect.Int32: "in.Int32()", + reflect.Int64: "in.Int64()", + reflect.Uint: "in.Uint()", + reflect.Uint8: "in.Uint8()", + reflect.Uint16: "in.Uint16()", + reflect.Uint32: "in.Uint32()", + reflect.Uint64: "in.Uint64()", + reflect.Float32: "in.Float32()", + reflect.Float64: "in.Float64()", +} + +var primitiveStringDecoders = map[reflect.Kind]string{ + reflect.String: "in.String()", + reflect.Int: "in.IntStr()", + reflect.Int8: "in.Int8Str()", + reflect.Int16: "in.Int16Str()", + reflect.Int32: "in.Int32Str()", + reflect.Int64: "in.Int64Str()", + reflect.Uint: "in.UintStr()", + reflect.Uint8: "in.Uint8Str()", + reflect.Uint16: "in.Uint16Str()", + reflect.Uint32: "in.Uint32Str()", + reflect.Uint64: "in.Uint64Str()", + reflect.Uintptr: "in.UintptrStr()", +} + +var customDecoders = map[string]string{ + "json.Number": "in.JsonNumber()", +} + +// genTypeDecoder generates decoding code for the type t, but uses unmarshaler interface if implemented by t. +func (g *Generator) genTypeDecoder(t reflect.Type, out string, tags fieldTags, indent int) error { + ws := strings.Repeat(" ", indent) + + unmarshalerIface := reflect.TypeOf((*easyjson.Unmarshaler)(nil)).Elem() + if reflect.PtrTo(t).Implements(unmarshalerIface) { + fmt.Fprintln(g.out, ws+"("+out+").UnmarshalEasyJSON(in)") + return nil + } + + unmarshalerIface = reflect.TypeOf((*json.Unmarshaler)(nil)).Elem() + if reflect.PtrTo(t).Implements(unmarshalerIface) { + fmt.Fprintln(g.out, ws+"if data := in.Raw(); in.Ok() {") + fmt.Fprintln(g.out, ws+" in.AddError( ("+out+").UnmarshalJSON(data) )") + fmt.Fprintln(g.out, ws+"}") + return nil + } + + unmarshalerIface = reflect.TypeOf((*encoding.TextUnmarshaler)(nil)).Elem() + if reflect.PtrTo(t).Implements(unmarshalerIface) { + fmt.Fprintln(g.out, ws+"if data := in.UnsafeBytes(); in.Ok() {") + fmt.Fprintln(g.out, ws+" in.AddError( ("+out+").UnmarshalText(data) )") + fmt.Fprintln(g.out, ws+"}") + return nil + } + + err := g.genTypeDecoderNoCheck(t, out, tags, indent) + return err +} + +// genTypeDecoderNoCheck generates decoding code for the type t. +func (g *Generator) genTypeDecoderNoCheck(t reflect.Type, out string, tags fieldTags, indent int) error { + ws := strings.Repeat(" ", indent) + // Check whether type is primitive, needs to be done after interface check. + if dec := customDecoders[t.String()]; dec != "" { + fmt.Fprintln(g.out, ws+out+" = "+dec) + return nil + } else if dec := primitiveStringDecoders[t.Kind()]; dec != "" && tags.asString { + fmt.Fprintln(g.out, ws+out+" = "+g.getType(t)+"("+dec+")") + return nil + } else if dec := primitiveDecoders[t.Kind()]; dec != "" { + fmt.Fprintln(g.out, ws+out+" = "+g.getType(t)+"("+dec+")") + return nil + } + + switch t.Kind() { + case reflect.Slice: + tmpVar := g.uniqueVarName() + elem := t.Elem() + + if elem.Kind() == reflect.Uint8 { + fmt.Fprintln(g.out, ws+"if in.IsNull() {") + fmt.Fprintln(g.out, ws+" in.Skip()") + fmt.Fprintln(g.out, ws+" "+out+" = nil") + fmt.Fprintln(g.out, ws+"} else {") + fmt.Fprintln(g.out, ws+" "+out+" = in.Bytes()") + fmt.Fprintln(g.out, ws+"}") + + } else { + + capacity := minSliceBytes / elem.Size() + if capacity == 0 { + capacity = 1 + } + + fmt.Fprintln(g.out, ws+"if in.IsNull() {") + fmt.Fprintln(g.out, ws+" in.Skip()") + fmt.Fprintln(g.out, ws+" "+out+" = nil") + fmt.Fprintln(g.out, ws+"} else {") + fmt.Fprintln(g.out, ws+" in.Delim('[')") + fmt.Fprintln(g.out, ws+" if "+out+" == nil {") + fmt.Fprintln(g.out, ws+" if !in.IsDelim(']') {") + fmt.Fprintln(g.out, ws+" "+out+" = make("+g.getType(t)+", 0, "+fmt.Sprint(capacity)+")") + fmt.Fprintln(g.out, ws+" } else {") + fmt.Fprintln(g.out, ws+" "+out+" = "+g.getType(t)+"{}") + fmt.Fprintln(g.out, ws+" }") + fmt.Fprintln(g.out, ws+" } else { ") + fmt.Fprintln(g.out, ws+" "+out+" = ("+out+")[:0]") + fmt.Fprintln(g.out, ws+" }") + fmt.Fprintln(g.out, ws+" for !in.IsDelim(']') {") + fmt.Fprintln(g.out, ws+" var "+tmpVar+" "+g.getType(elem)) + + if err := g.genTypeDecoder(elem, tmpVar, tags, indent+2); err != nil { + return err + } + + fmt.Fprintln(g.out, ws+" "+out+" = append("+out+", "+tmpVar+")") + fmt.Fprintln(g.out, ws+" in.WantComma()") + fmt.Fprintln(g.out, ws+" }") + fmt.Fprintln(g.out, ws+" in.Delim(']')") + fmt.Fprintln(g.out, ws+"}") + } + + case reflect.Array: + iterVar := g.uniqueVarName() + elem := t.Elem() + + if elem.Kind() == reflect.Uint8 { + fmt.Fprintln(g.out, ws+"if in.IsNull() {") + fmt.Fprintln(g.out, ws+" in.Skip()") + fmt.Fprintln(g.out, ws+"} else {") + fmt.Fprintln(g.out, ws+" copy("+out+"[:], in.Bytes())") + fmt.Fprintln(g.out, ws+"}") + + } else { + + length := t.Len() + + fmt.Fprintln(g.out, ws+"if in.IsNull() {") + fmt.Fprintln(g.out, ws+" in.Skip()") + fmt.Fprintln(g.out, ws+"} else {") + fmt.Fprintln(g.out, ws+" in.Delim('[')") + fmt.Fprintln(g.out, ws+" "+iterVar+" := 0") + fmt.Fprintln(g.out, ws+" for !in.IsDelim(']') {") + fmt.Fprintln(g.out, ws+" if "+iterVar+" < "+fmt.Sprint(length)+" {") + + if err := g.genTypeDecoder(elem, out+"["+iterVar+"]", tags, indent+3); err != nil { + return err + } + + fmt.Fprintln(g.out, ws+" "+iterVar+"++") + fmt.Fprintln(g.out, ws+" } else {") + fmt.Fprintln(g.out, ws+" in.SkipRecursive()") + fmt.Fprintln(g.out, ws+" }") + fmt.Fprintln(g.out, ws+" in.WantComma()") + fmt.Fprintln(g.out, ws+" }") + fmt.Fprintln(g.out, ws+" in.Delim(']')") + fmt.Fprintln(g.out, ws+"}") + } + + case reflect.Struct: + dec := g.getDecoderName(t) + g.addType(t) + + fmt.Fprintln(g.out, ws+dec+"(in, &"+out+")") + + case reflect.Ptr: + fmt.Fprintln(g.out, ws+"if in.IsNull() {") + fmt.Fprintln(g.out, ws+" in.Skip()") + fmt.Fprintln(g.out, ws+" "+out+" = nil") + fmt.Fprintln(g.out, ws+"} else {") + fmt.Fprintln(g.out, ws+" if "+out+" == nil {") + fmt.Fprintln(g.out, ws+" "+out+" = new("+g.getType(t.Elem())+")") + fmt.Fprintln(g.out, ws+" }") + + if err := g.genTypeDecoder(t.Elem(), "*"+out, tags, indent+1); err != nil { + return err + } + + fmt.Fprintln(g.out, ws+"}") + + case reflect.Map: + key := t.Key() + keyDec, ok := primitiveStringDecoders[key.Kind()] + if !ok { + return fmt.Errorf("map type %v not supported: only string and integer keys are allowed", key) + } + elem := t.Elem() + tmpVar := g.uniqueVarName() + + fmt.Fprintln(g.out, ws+"if in.IsNull() {") + fmt.Fprintln(g.out, ws+" in.Skip()") + fmt.Fprintln(g.out, ws+"} else {") + fmt.Fprintln(g.out, ws+" in.Delim('{')") + fmt.Fprintln(g.out, ws+" if !in.IsDelim('}') {") + fmt.Fprintln(g.out, ws+" "+out+" = make("+g.getType(t)+")") + fmt.Fprintln(g.out, ws+" } else {") + fmt.Fprintln(g.out, ws+" "+out+" = nil") + fmt.Fprintln(g.out, ws+" }") + + fmt.Fprintln(g.out, ws+" for !in.IsDelim('}') {") + fmt.Fprintln(g.out, ws+" key := "+g.getType(key)+"("+keyDec+")") + fmt.Fprintln(g.out, ws+" in.WantColon()") + fmt.Fprintln(g.out, ws+" var "+tmpVar+" "+g.getType(elem)) + + if err := g.genTypeDecoder(elem, tmpVar, tags, indent+2); err != nil { + return err + } + + fmt.Fprintln(g.out, ws+" ("+out+")[key] = "+tmpVar) + fmt.Fprintln(g.out, ws+" in.WantComma()") + fmt.Fprintln(g.out, ws+" }") + fmt.Fprintln(g.out, ws+" in.Delim('}')") + fmt.Fprintln(g.out, ws+"}") + + case reflect.Interface: + if t.NumMethod() != 0 { + return fmt.Errorf("interface type %v not supported: only interface{} is allowed", t) + } + fmt.Fprintln(g.out, ws+"if m, ok := "+out+".(easyjson.Unmarshaler); ok {") + fmt.Fprintln(g.out, ws+"m.UnmarshalEasyJSON(in)") + fmt.Fprintln(g.out, ws+"} else if m, ok := "+out+".(json.Unmarshaler); ok {") + fmt.Fprintln(g.out, ws+"_ = m.UnmarshalJSON(in.Raw())") + fmt.Fprintln(g.out, ws+"} else {") + fmt.Fprintln(g.out, ws+" "+out+" = in.Interface()") + fmt.Fprintln(g.out, ws+"}") + default: + return fmt.Errorf("don't know how to decode %v", t) + } + return nil + +} + +func (g *Generator) genStructFieldDecoder(t reflect.Type, f reflect.StructField) error { + jsonName := g.fieldNamer.GetJSONFieldName(t, f) + tags := parseFieldTags(f) + + if tags.omit { + return nil + } + + fmt.Fprintf(g.out, " case %q:\n", jsonName) + if err := g.genTypeDecoder(f.Type, "out."+f.Name, tags, 3); err != nil { + return err + } + + if tags.required { + fmt.Fprintf(g.out, "%sSet = true\n", f.Name) + } + + return nil +} + +func (g *Generator) genRequiredFieldSet(t reflect.Type, f reflect.StructField) { + tags := parseFieldTags(f) + + if !tags.required { + return + } + + fmt.Fprintf(g.out, "var %sSet bool\n", f.Name) +} + +func (g *Generator) genRequiredFieldCheck(t reflect.Type, f reflect.StructField) { + jsonName := g.fieldNamer.GetJSONFieldName(t, f) + tags := parseFieldTags(f) + + if !tags.required { + return + } + + g.imports["fmt"] = "fmt" + + fmt.Fprintf(g.out, "if !%sSet {\n", f.Name) + fmt.Fprintf(g.out, " in.AddError(fmt.Errorf(\"key '%s' is required\"))\n", jsonName) + fmt.Fprintf(g.out, "}\n") +} + +func mergeStructFields(fields1, fields2 []reflect.StructField) (fields []reflect.StructField) { + used := map[string]bool{} + for _, f := range fields2 { + used[f.Name] = true + fields = append(fields, f) + } + + for _, f := range fields1 { + if !used[f.Name] { + fields = append(fields, f) + } + } + return +} + +func getStructFields(t reflect.Type) ([]reflect.StructField, error) { + if t.Kind() != reflect.Struct { + return nil, fmt.Errorf("got %v; expected a struct", t) + } + + var efields []reflect.StructField + for i := 0; i < t.NumField(); i++ { + f := t.Field(i) + if !f.Anonymous { + continue + } + + t1 := f.Type + if t1.Kind() == reflect.Ptr { + t1 = t1.Elem() + } + + fs, err := getStructFields(t1) + if err != nil { + return nil, fmt.Errorf("error processing embedded field: %v", err) + } + efields = mergeStructFields(efields, fs) + } + + var fields []reflect.StructField + for i := 0; i < t.NumField(); i++ { + f := t.Field(i) + if f.Anonymous { + continue + } + + c := []rune(f.Name)[0] + if unicode.IsUpper(c) { + fields = append(fields, f) + } + } + return mergeStructFields(efields, fields), nil +} + +func (g *Generator) genDecoder(t reflect.Type) error { + switch t.Kind() { + case reflect.Slice, reflect.Array, reflect.Map: + return g.genSliceArrayDecoder(t) + default: + return g.genStructDecoder(t) + } +} + +func (g *Generator) genSliceArrayDecoder(t reflect.Type) error { + switch t.Kind() { + case reflect.Slice, reflect.Array, reflect.Map: + default: + return fmt.Errorf("cannot generate encoder/decoder for %v, not a slice/array/map type", t) + } + + fname := g.getDecoderName(t) + typ := g.getType(t) + + fmt.Fprintln(g.out, "func "+fname+"(in *jlexer.Lexer, out *"+typ+") {") + fmt.Fprintln(g.out, " isTopLevel := in.IsStart()") + err := g.genTypeDecoderNoCheck(t, "*out", fieldTags{}, 1) + if err != nil { + return err + } + fmt.Fprintln(g.out, " if isTopLevel {") + fmt.Fprintln(g.out, " in.Consumed()") + fmt.Fprintln(g.out, " }") + fmt.Fprintln(g.out, "}") + + return nil +} + +func (g *Generator) genStructDecoder(t reflect.Type) error { + if t.Kind() != reflect.Struct { + return fmt.Errorf("cannot generate encoder/decoder for %v, not a struct type", t) + } + + fname := g.getDecoderName(t) + typ := g.getType(t) + + fmt.Fprintln(g.out, "func "+fname+"(in *jlexer.Lexer, out *"+typ+") {") + fmt.Fprintln(g.out, " isTopLevel := in.IsStart()") + fmt.Fprintln(g.out, " if in.IsNull() {") + fmt.Fprintln(g.out, " if isTopLevel {") + fmt.Fprintln(g.out, " in.Consumed()") + fmt.Fprintln(g.out, " }") + fmt.Fprintln(g.out, " in.Skip()") + fmt.Fprintln(g.out, " return") + fmt.Fprintln(g.out, " }") + + // Init embedded pointer fields. + for i := 0; i < t.NumField(); i++ { + f := t.Field(i) + if !f.Anonymous || f.Type.Kind() != reflect.Ptr { + continue + } + fmt.Fprintln(g.out, " out."+f.Name+" = new("+g.getType(f.Type.Elem())+")") + } + + fs, err := getStructFields(t) + if err != nil { + return fmt.Errorf("cannot generate decoder for %v: %v", t, err) + } + + for _, f := range fs { + g.genRequiredFieldSet(t, f) + } + + fmt.Fprintln(g.out, " in.Delim('{')") + fmt.Fprintln(g.out, " for !in.IsDelim('}') {") + fmt.Fprintln(g.out, " key := in.UnsafeString()") + fmt.Fprintln(g.out, " in.WantColon()") + fmt.Fprintln(g.out, " if in.IsNull() {") + fmt.Fprintln(g.out, " in.Skip()") + fmt.Fprintln(g.out, " in.WantComma()") + fmt.Fprintln(g.out, " continue") + fmt.Fprintln(g.out, " }") + + fmt.Fprintln(g.out, " switch key {") + for _, f := range fs { + if err := g.genStructFieldDecoder(t, f); err != nil { + return err + } + } + + fmt.Fprintln(g.out, " default:") + fmt.Fprintln(g.out, " in.SkipRecursive()") + fmt.Fprintln(g.out, " }") + fmt.Fprintln(g.out, " in.WantComma()") + fmt.Fprintln(g.out, " }") + fmt.Fprintln(g.out, " in.Delim('}')") + fmt.Fprintln(g.out, " if isTopLevel {") + fmt.Fprintln(g.out, " in.Consumed()") + fmt.Fprintln(g.out, " }") + + for _, f := range fs { + g.genRequiredFieldCheck(t, f) + } + + fmt.Fprintln(g.out, "}") + + return nil +} + +func (g *Generator) genStructUnmarshaler(t reflect.Type) error { + switch t.Kind() { + case reflect.Slice, reflect.Array, reflect.Map, reflect.Struct: + default: + return fmt.Errorf("cannot generate encoder/decoder for %v, not a struct/slice/array/map type", t) + } + + fname := g.getDecoderName(t) + typ := g.getType(t) + + if !g.noStdMarshalers { + fmt.Fprintln(g.out, "// UnmarshalJSON supports json.Unmarshaler interface") + fmt.Fprintln(g.out, "func (v *"+typ+") UnmarshalJSON(data []byte) error {") + fmt.Fprintln(g.out, " r := jlexer.Lexer{Data: data}") + fmt.Fprintln(g.out, " "+fname+"(&r, v)") + fmt.Fprintln(g.out, " return r.Error()") + fmt.Fprintln(g.out, "}") + } + + fmt.Fprintln(g.out, "// UnmarshalEasyJSON supports easyjson.Unmarshaler interface") + fmt.Fprintln(g.out, "func (v *"+typ+") UnmarshalEasyJSON(l *jlexer.Lexer) {") + fmt.Fprintln(g.out, " "+fname+"(l, v)") + fmt.Fprintln(g.out, "}") + + return nil +} |