feat: support generating map[type]struct{} for IDL Set

generator/golang/option.go

@@ -52,8 +52,8 @@ type Features struct {
 	EnumAsINT32                 bool `enum_as_int_32:"Generate enum type as int32"`
 	CodeRefSlim                 bool `code_ref_slim:"Generate code ref by given idl-ref.yaml with less refs to avoid conflict"`
 	CodeRef                     bool `code_ref:"Generate code ref by given idl-ref.yaml"`
-	ExpCodeRef             bool `exp_code_ref:"Generate code ref by given idl-ref.yaml with less refs to avoid conflict, but remind some struct as local.( this is a exp feature )"`
-  KeepCodeRefName             bool `keep_code_ref_name:"Generate code ref but still keep file name."`
+	ExpCodeRef                  bool `exp_code_ref:"Generate code ref by given idl-ref.yaml with less refs to avoid conflict, but remind some struct as local.( this is a exp feature )"`
+	KeepCodeRefName             bool `keep_code_ref_name:"Generate code ref but still keep file name."`
 	TrimIDL                     bool `trim_idl:"Simplify IDL to the most concise form before generating code."`
 	EnableNestedStruct          bool `enable_nested_struct:"Generate nested field when 'thrift.nested=\"true\"' annotation is set to field, valid only in 'slim and raw_struct template'"`
 	JSONStringer                bool `json_stringer:"Generate the JSON marshal method in String() method."`
@@ -70,6 +70,7 @@ type Features struct {
 	SkipEmpty         bool `skip_empty:"If there's not content in file, just skip it. Later this feature will be a default feature."`
 	NoProcessor       bool `no_processor:" Do not generate default thrift processor and client. Later this feature will be a default feature."`
 	GetEnumAnnotation bool `get_enum_annotation:"Generate GetAnnotation method for enum types."`
+	GenMapForIDLSet   bool `gen_map_for_idl_set:"Generate map[type]struct{} instead of []type for IDL set."`
 }
 
 var defaultFeatures = Features{
@@ -108,6 +109,7 @@ var defaultFeatures = Features{
 	NoAliasTypeReflectionMethod: false,
 	EnableRefInterface:          false,
 	GetEnumAnnotation:           false,
+	GenMapForIDLSet:             false,
 }
 
 type param struct {

generator/golang/read_write_context.go

@@ -39,6 +39,8 @@ type ReadWriteContext struct {
 	ids map[string]int // Prefix => local variable index
 
 	FieldMask string
+
+	IsGenMap bool // whether set field would be generated as map
 }
 
 // GenID returns a local variable with the given name as prefix.
@@ -132,5 +134,13 @@ func mkRWCtx(r *Resolver, s *Scope, t *parser.Type, top *ReadWriteContext) (*Rea
 		}
 	}
 
+	if r.util.Features().GenMapForIDLSet && t.Category == parser.Category_Set {
+		ctx.IsGenMap = true
+		// since we can not use []byte as the key of map, convert it to string
+		if ctx.ValCtx.TypeID == typeids.Binary {
+			ctx.ValCtx.TypeName = "string"
+		}
+	}
+
 	return ctx, nil
 }

generator/golang/resolver.go

@@ -123,16 +123,23 @@ func (r *Resolver) getTypeName(g *Scope, t *parser.Type) (name string, err error
 }
 
 func (r *Resolver) getContainerTypeName(g *Scope, t *parser.Type) (name string, err error) {
-	if t.Name == "map" {
+	// when isGenMapForIDLSet is true, the generated code for set would be map[type]struct{}
+	isGenMapForIDLSet := r.util.Features().GenMapForIDLSet && t.Name == "set"
+	if t.Name == "map" || isGenMapForIDLSet {
 		var k string
-		if t.KeyType.Category == parser.Category_Binary {
+		keyType := t.KeyType
+		if t.Name == "set" {
+			keyType = t.ValueType
+		}
+
+		if keyType.Category == parser.Category_Binary {
 			k = "string" // 'binary => string' for key type in map
 		} else {
-			k, err = r.getTypeName(g, t.KeyType)
+			k, err = r.getTypeName(g, keyType)
 			if err != nil {
 				return "", fmt.Errorf("resolve key type of '%s' failed: %w", t, err)
 			}
-			if t.KeyType.Category.IsStructLike() && !checkRefInterfaceType(r.util, g, t.KeyType) {
+			if keyType.Category.IsStructLike() && !checkRefInterfaceType(r.util, g, keyType) {
 				// when a struct-like is used as key of a map, it must
 				// generte a pointer type instead of the struct itself
 				k = "*" + k
@@ -143,14 +150,19 @@ func (r *Resolver) getContainerTypeName(g *Scope, t *parser.Type) (name string,
 		name = "[]" // sets and lists compile into slices
 	}
 
-	v, err := r.getTypeName(g, t.ValueType)
-	if err != nil {
-		return "", fmt.Errorf("resolve value type of '%s' failed: %w", t, err)
+	var v string
+	if isGenMapForIDLSet {
+		v = "struct{}"
+	} else {
+		v, err = r.getTypeName(g, t.ValueType)
+		if err != nil {
+			return "", fmt.Errorf("resolve value type of '%s' failed: %w", t, err)
+		}
+		if t.ValueType.Category.IsStructLike() && !r.util.Features().ValueTypeForSIC && !checkRefInterfaceType(r.util, g, t.ValueType) {
+			v = "*" + v // generate pointer type for struct-like by default
+		}
 	}
 
-	if t.ValueType.Category.IsStructLike() && !r.util.Features().ValueTypeForSIC && !checkRefInterfaceType(r.util, g, t.ValueType) {
-		v = "*" + v // generate pointer type for struct-like by default
-	}
 	return name + v, nil // map[k]v or []v
 }
 
@@ -348,7 +360,11 @@ func (r *Resolver) onSetOrList(g *Scope, name string, t *parser.Type, v *parser.
 			if err != nil {
 				return "", err
 			}
-			ss = append(ss, str+",")
+			if !r.util.Features().GenMapForIDLSet {
+				ss = append(ss, str+",")
+			} else {
+				ss = append(ss, fmt.Sprintf("%s: struct{}{},", str))
+			}
 		}
 		if len(ss) == 0 {
 			return goType + "{}", nil

generator/golang/templates/struct.go

@@ -675,13 +675,18 @@ var FieldReadMap = `
 var FieldReadSet = `
 {{define "FieldReadSet"}}
 {{- $isBaseVal := .ValCtx.Type | IsBaseType -}}
+{{- $isGenMap := .IsGenMap -}}
 {{- $curFieldMask := .FieldMask -}}
 {{- $isStructVal := .ValCtx.Type.Category.IsStructLike -}}
 	_, size, err := iprot.ReadSetBegin()
 	if err != nil {
 		return err
 	}
+    {{- if $isGenMap}}
+    {{.Target}} {{if .NeedDecl}}:{{end}}= make({{.TypeName}}, size)
+    {{- else}}
 	{{.Target}} {{if .NeedDecl}}:{{end}}= make({{.TypeName}}, 0, size)
+    {{- end}}
 	{{- if $isStructVal}}
 	values := make([]{{.ValCtx.TypeName.Deref}}, size)
 	{{- end}}
@@ -708,8 +713,12 @@ var FieldReadSet = `
 		{{if and .ValCtx.Type.Category.IsStructLike Features.ValueTypeForSIC}}
 			{{$val = printf "*%s" $val}}
 		{{end}}
-
+
+        {{- if $isGenMap}}
+        {{.Target}}[{{$val}}] = struct{}{}
+		{{- else}}
 		{{.Target}} = append({{.Target}}, {{$val}})
+		{{- end}}
 		{{- if Features.WithFieldMask}}
 		}
 		{{- end}}
@@ -904,6 +913,7 @@ var FieldWriteSet = `
 {{define "FieldWriteSet"}}
 {{- $isBaseVal := .ValCtx.Type | IsBaseType -}}
 {{- $curFieldMask := .FieldMask -}}
+{{- $isGenMap := .IsGenMap -}}
 		{{- if Features.WithFieldMask}}
 		if !{{.FieldMask}}.All() {
 			l := len({{.Target}})
@@ -931,7 +941,7 @@ var FieldWriteSet = `
 			return err
 		}
 		{{- end}}
-		{{- if Features.ValidateSet}}
+		{{- if and Features.ValidateSet (not $isGenMap)}}
 		{{- $ctx := (.ValCtx.WithTarget "tgt").WithSource "src"}}
 		for i := 0; i < len({{.Target}}); i++ {
 			for j := i + 1; j < len({{.Target}}); j++ {
@@ -950,7 +960,7 @@ var FieldWriteSet = `
 			}
 		}
 		{{- end}}
-		for {{if Features.WithFieldMask}}i{{else}}_{{end}}, v := range {{.Target}} {
+		for {{if not $isGenMap}}{{if Features.WithFieldMask }}i{{else}}_{{end}}, {{end}}v := range {{.Target}} {
 			{{- if Features.WithFieldMask}}
 			{{- $curFieldMask = "nfm"}}
 			if {{if $isBaseVal}}_{{else}}{{$curFieldMask}}{{end}}, ex := {{.FieldMask}}.Int(i); !ex {

generator/golang/util.go

@@ -97,7 +97,7 @@ func (cu *CodeUtils) Features() Features {
 	return cu.features
 }
 
-// GetPackagePrefix sets the package prefix in generated codes.
+// GetPackagePrefix gets the package prefix in generated codes.
 func (cu *CodeUtils) GetPackagePrefix() (pp string) {
 	return cu.packagePrefix
 }