add Marshal functions for struct with many types

- ChatBoostSource
- ChatBackground
- ChatMember
- MenuButton
- MaybeInaccessibleMessage
- ReactionType
- MessageOrigin

methods_test.go

@@ -681,7 +681,7 @@ func TestBot_Methods(t *testing.T) {
 			ChatID: 123,
 		})
 		assertNoErr(t, err)
-		assertEqualInt(t, int(models.ChatMemberTypeAdministrator), int(resp.Type))
+		assertEqualString(t, string(models.ChatMemberTypeAdministrator), string(resp.Type))
 	})
 
 	t.Run("SetChatStickerSet", func(t *testing.T) {

models/boost.go

@@ -48,23 +48,23 @@ type ChatBoostSource struct {
 
 func (cbs *ChatBoostSource) UnmarshalJSON(data []byte) error {
 	v := struct {
-		Source string `json:"source"`
+		Source ChatBoostSourceType `json:"source"`
 	}{}
 	err := json.Unmarshal(data, &v)
 	if err != nil {
 		return err
 	}
 
 	switch v.Source {
-	case "premium":
+	case ChatBoostSourceTypePremium:
 		cbs.Source = ChatBoostSourceTypePremium
 		cbs.ChatBoostSourcePremium = &ChatBoostSourcePremium{}
 		return json.Unmarshal(data, cbs.ChatBoostSourcePremium)
-	case "gift_code":
+	case ChatBoostSourceTypeGiftCode:
 		cbs.Source = ChatBoostSourceTypeGiftCode
 		cbs.ChatBoostSourceGiftCode = &ChatBoostSourceGiftCode{}
 		return json.Unmarshal(data, cbs.ChatBoostSourceGiftCode)
-	case "giveaway":
+	case ChatBoostSourceTypeGiveaway:
 		cbs.Source = ChatBoostSourceTypeGiveaway
 		cbs.ChatBoostSourceGiveaway = &ChatBoostSourceGiveaway{}
 		return json.Unmarshal(data, cbs.ChatBoostSourceGiveaway)
@@ -73,29 +73,45 @@ func (cbs *ChatBoostSource) UnmarshalJSON(data []byte) error {
 	return fmt.Errorf("unsupported ChatBoostSource type")
 }
 
+func (cbs *ChatBoostSource) MarshalJSON() ([]byte, error) {
+	switch cbs.Source {
+	case ChatBoostSourceTypePremium:
+		cbs.ChatBoostSourcePremium.Source = ChatBoostSourceTypePremium
+		return json.Marshal(cbs.ChatBoostSourcePremium)
+	case ChatBoostSourceTypeGiftCode:
+		cbs.ChatBoostSourceGiftCode.Source = ChatBoostSourceTypeGiftCode
+		return json.Marshal(cbs.ChatBoostSourceGiftCode)
+	case ChatBoostSourceTypeGiveaway:
+		cbs.ChatBoostSourceGiveaway.Source = ChatBoostSourceTypeGiveaway
+		return json.Marshal(cbs.ChatBoostSourceGiveaway)
+	}
+
+	return nil, fmt.Errorf("unsupported ChatBoostSource type")
+}
+
 // ChatBoostSourceType https://core.telegram.org/bots/api#chatboostsource
-type ChatBoostSourceType int
+type ChatBoostSourceType string
 
 const (
-	ChatBoostSourceTypePremium ChatBoostSourceType = iota
-	ChatBoostSourceTypeGiftCode
-	ChatBoostSourceTypeGiveaway
+	ChatBoostSourceTypePremium  ChatBoostSourceType = "premium"
+	ChatBoostSourceTypeGiftCode ChatBoostSourceType = "gift_code"
+	ChatBoostSourceTypeGiveaway ChatBoostSourceType = "giveaway"
 )
 
 // ChatBoostSourcePremium https://core.telegram.org/bots/api#chatboostsourcepremium
 type ChatBoostSourcePremium struct {
-	Source string `json:"source"` // always “premium”
-	User   User   `json:"user"`
+	Source ChatBoostSourceType `json:"source"` // always “premium”
+	User   User                `json:"user"`
 }
 
 // ChatBoostSourceGiftCode https://core.telegram.org/bots/api#chatboostsourcegiftcode
 type ChatBoostSourceGiftCode struct {
-	Source string `json:"source"` // always “gift_code”
-	User   User   `json:"user"`
+	Source ChatBoostSourceType `json:"source"` // always “gift_code”
+	User   User                `json:"user"`
 }
 
 // ChatBoostSourceGiveaway https://core.telegram.org/bots/api#chatboostsourcegiveaway
 type ChatBoostSourceGiveaway struct {
-	Source string `json:"source"` // always “giveaway”
-	User   User   `json:"user"`
+	Source ChatBoostSourceType `json:"source"` // always “giveaway”
+	User   User                `json:"user"`
 }

models/boost_test.go

@@ -70,3 +70,48 @@ func TestChatBoostSource_giveaway(t *testing.T) {
 		t.Fatal("invalid user id")
 	}
 }
+
+func TestChatBoostSource_premium_marshal_unmarshal(t *testing.T) {
+	src := `{"source":"premium","user":{"id":123}}`
+
+	cbs := &ChatBoostSource{}
+	err := json.Unmarshal([]byte(src), cbs)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	if cbs.Source != ChatBoostSourceTypePremium {
+		t.Fatal("invalid type")
+	}
+
+	if cbs.ChatBoostSourcePremium == nil {
+		t.Fatal("invalid ChatBoostSourcePremium")
+	}
+
+	if cbs.ChatBoostSourcePremium.User.ID != 123 {
+		t.Fatal("invalid user id")
+	}
+
+	src2, err2 := json.Marshal(cbs)
+	if err2 != nil {
+		t.Fatal(err2)
+	}
+
+	var cbs2 ChatBoostSource
+	err = json.Unmarshal(src2, &cbs2)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	if cbs2.Source != ChatBoostSourceTypePremium {
+		t.Fatal("invalid type")
+	}
+
+	if cbs2.ChatBoostSourcePremium == nil {
+		t.Fatal("invalid ChatBoostSourcePremium")
+	}
+
+	if cbs2.ChatBoostSourcePremium.User.ID != 123 {
+		t.Fatal("invalid user id")
+	}
+}

models/chat_background.go

@@ -26,26 +26,26 @@ type ChatBackground struct {
 
 func (cb *ChatBackground) UnmarshalJSON(data []byte) error {
 	v := struct {
-		Type string `json:"type"`
+		Type BackgroundType `json:"type"`
 	}{}
 	if err := json.Unmarshal(data, &v); err != nil {
 		return err
 	}
 
 	switch v.Type {
-	case "fill":
+	case ChatBackgroundTypeFill:
 		cb.Type = ChatBackgroundTypeFill
 		cb.Fill = &BackgroundTypeFill{}
 		return json.Unmarshal(data, cb.Fill)
-	case "wallpaper":
+	case ChatBackgroundTypeWallpaper:
 		cb.Type = ChatBackgroundTypeWallpaper
 		cb.Wallpaper = &BackgroundTypeWallpaper{}
 		return json.Unmarshal(data, cb.Wallpaper)
-	case "pattern":
+	case ChatBackgroundTypePattern:
 		cb.Type = ChatBackgroundTypePattern
 		cb.Pattern = &BackgroundTypePattern{}
 		return json.Unmarshal(data, cb.Pattern)
-	case "chat_theme":
+	case ChatBackgroundTypeChatTheme:
 		cb.Type = ChatBackgroundTypeChatTheme
 		cb.Theme = &BackgroundTypeChatTheme{}
 		return json.Unmarshal(data, cb.Theme)
@@ -54,22 +54,44 @@ func (cb *ChatBackground) UnmarshalJSON(data []byte) error {
 	return fmt.Errorf("unsupported ChatBackground type")
 }
 
+func (cb *ChatBackground) MarshalJSON() ([]byte, error) {
+	switch cb.Type {
+	case ChatBackgroundTypeFill:
+		cb.Fill.Type = ChatBackgroundTypeFill
+		return json.Marshal(cb.Fill)
+	case ChatBackgroundTypeWallpaper:
+		cb.Wallpaper.Type = ChatBackgroundTypeWallpaper
+		return json.Marshal(cb.Wallpaper)
+	case ChatBackgroundTypePattern:
+		cb.Pattern.Type = ChatBackgroundTypePattern
+		return json.Marshal(cb.Pattern)
+	case ChatBackgroundTypeChatTheme:
+		cb.Theme.Type = ChatBackgroundTypeChatTheme
+		return json.Marshal(cb.Theme)
+	}
+
+	return nil, fmt.Errorf("unsupported ChatBackground type")
+}
+
 // BackgroundTypeFill https://core.telegram.org/bots/api#backgroundtypefill
 type BackgroundTypeFill struct {
+	Type             BackgroundType `json:"type"`
 	Fill             BackgroundFill `json:"fill"`
 	DarkThemeDimming int            `json:"dark_theme_dimming"`
 }
 
 // BackgroundTypeWallpaper https://core.telegram.org/bots/api#backgroundtypewallpaper
 type BackgroundTypeWallpaper struct {
-	Document         Document `json:"document"`
-	DarkThemeDimming int      `json:"dark_theme_dimming"`
-	IsBlurred        bool     `json:"is_blurred,omitempty"`
-	IsMoving         bool     `json:"is_moving,omitempty"`
+	Type             BackgroundType `json:"type"`
+	Document         Document       `json:"document"`
+	DarkThemeDimming int            `json:"dark_theme_dimming"`
+	IsBlurred        bool           `json:"is_blurred,omitempty"`
+	IsMoving         bool           `json:"is_moving,omitempty"`
 }
 
 // BackgroundTypePattern https://core.telegram.org/bots/api#backgroundtypepattern
 type BackgroundTypePattern struct {
+	Type       BackgroundType `json:"type"`
 	Document   Document       `json:"document"`
 	Fill       BackgroundFill `json:"fill"`
 	Intensity  int            `json:"intensity"`
@@ -79,7 +101,8 @@ type BackgroundTypePattern struct {
 
 // BackgroundTypeChatTheme https://core.telegram.org/bots/api#backgroundtypechattheme
 type BackgroundTypeChatTheme struct {
-	ThemeName string `json:"theme_name"`
+	Type      BackgroundType `json:"type"`
+	ThemeName string         `json:"theme_name"`
 }
 
 type BackgroundFillType string
@@ -91,30 +114,30 @@ const (
 )
 
 type BackgroundFill struct {
-	Type             BackgroundFillType `json:"type"`
+	Type             BackgroundFillType
 	Solid            *BackgroundFillSolid
 	Gradient         *BackgroundFillGradient
 	FreeformGradient *BackgroundFillFreeformGradient
 }
 
 func (bf *BackgroundFill) UnmarshalJSON(data []byte) error {
 	v := struct {
-		Type string `json:"type"`
+		Type BackgroundFillType `json:"type"`
 	}{}
 	if err := json.Unmarshal(data, &v); err != nil {
 		return err
 	}
 
 	switch v.Type {
-	case "solid":
+	case BackgroundFillTypeSolid:
 		bf.Type = BackgroundFillTypeSolid
 		bf.Solid = &BackgroundFillSolid{}
 		return json.Unmarshal(data, bf.Solid)
-	case "gradient":
+	case BackgroundFillTypeGradient:
 		bf.Type = BackgroundFillTypeGradient
 		bf.Gradient = &BackgroundFillGradient{}
 		return json.Unmarshal(data, bf.Gradient)
-	case "freeform_gradient":
+	case BackgroundFillTypeFreeformGradient:
 		bf.Type = BackgroundFillTypeFreeformGradient
 		bf.FreeformGradient = &BackgroundFillFreeformGradient{}
 		return json.Unmarshal(data, bf.FreeformGradient)
@@ -123,19 +146,38 @@ func (bf *BackgroundFill) UnmarshalJSON(data []byte) error {
 	return fmt.Errorf("unsupported BackgroundFill type")
 }
 
+func (bf *BackgroundFill) MarshalJSON() ([]byte, error) {
+	switch bf.Type {
+	case BackgroundFillTypeSolid:
+		bf.Solid.Type = BackgroundFillTypeSolid
+		return json.Marshal(bf.Solid)
+	case BackgroundFillTypeGradient:
+		bf.Gradient.Type = BackgroundFillTypeGradient
+		return json.Marshal(bf.Gradient)
+	case BackgroundFillTypeFreeformGradient:
+		bf.FreeformGradient.Type = BackgroundFillTypeFreeformGradient
+		return json.Marshal(bf.FreeformGradient)
+	}
+
+	return nil, fmt.Errorf("unsupported BackgroundFill type")
+}
+
 // BackgroundFillSolid https://core.telegram.org/bots/api#backgroundfillsolid
 type BackgroundFillSolid struct {
-	Color int `json:"color"`
+	Type  BackgroundFillType `json:"type"`
+	Color int                `json:"color"`
 }
 
 // BackgroundFillGradient https://core.telegram.org/bots/api#backgroundfillgradient
 type BackgroundFillGradient struct {
-	TopColor      int `json:"top_color"`
-	BottomColor   int `json:"bottom_color"`
-	RotationAngle int `json:"rotation_angle"`
+	Type          BackgroundFillType `json:"type"`
+	TopColor      int                `json:"top_color"`
+	BottomColor   int                `json:"bottom_color"`
+	RotationAngle int                `json:"rotation_angle"`
 }
 
 // BackgroundFillFreeformGradient https://core.telegram.org/bots/api#backgroundfillfreeformgradient
 type BackgroundFillFreeformGradient struct {
-	Colors []int `json:"colors"`
+	Type   BackgroundFillType `json:"type"`
+	Colors []int              `json:"colors"`
 }