Convert enum number into wrapper struct to save type sizes (serenity-…

…rs#2746)

Saves a couple bytes in each model by replacing the enums with a simpler
and more accurate representation, a newtype with named statics.
https://www.diffchecker.com/ohzayL9Z/

src/constants.rs

@@ -40,7 +40,6 @@ enum_number! {
     ///
     /// [Discord docs](https://discord.com/developers/docs/topics/opcodes-and-status-codes#gateway-gateway-opcodes).
     #[derive(Clone, Copy, Debug, Eq, Hash, Ord, PartialEq, PartialOrd, Deserialize, Serialize)]
-    #[serde(from = "u8", into = "u8")]
     #[non_exhaustive]
     pub enum Opcode {
         /// Dispatches an event.

src/internal/macros.rs

@@ -86,43 +86,39 @@ macro_rules! status {
 macro_rules! enum_number {
     (
         $(#[$outer:meta])*
+        $(#[<default> = $default:literal])?
         $vis:vis enum $Enum:ident {
             $(
                 $(#[doc = $doc:literal])*
                 $(#[cfg $($cfg:tt)*])?
-                $(#[default $($dummy:tt)?])?
                 $Variant:ident = $value:literal,
             )*
             _ => Unknown($T:ty),
         }
     ) => {
         $(#[$outer])*
-        $vis enum $Enum {
+        $vis struct $Enum (pub $T);
+
+        $(
+            impl Default for $Enum {
+                fn default() -> Self {
+                    Self($default)
+                }
+            }
+        )?
+
+        #[allow(non_snake_case, non_upper_case_globals)]
+        impl $Enum {
             $(
                 $(#[doc = $doc])*
                 $(#[cfg $($cfg)*])?
-                $(#[default $($dummy:tt)?])?
-                $Variant,
+                $vis const $Variant: Self = Self($value);
             )*
-            /// Variant value is unknown.
-            Unknown($T),
-        }
 
-        impl From<$T> for $Enum {
-            fn from(value: $T) -> Self {
-                match value {
-                    $($(#[cfg $($cfg)*])? $value => Self::$Variant,)*
-                    unknown => Self::Unknown(unknown),
-                }
-            }
-        }
-
-        impl From<$Enum> for $T {
-            fn from(value: $Enum) -> Self {
-                match value {
-                    $($(#[cfg $($cfg)*])? $Enum::$Variant => $value,)*
-                    $Enum::Unknown(unknown) => unknown,
-                }
+            /// Variant value is unknown.
+            #[must_use]
+            $vis const fn Unknown(val: $T) -> Self {
+                Self(val)
             }
         }
     };
@@ -184,7 +180,6 @@ mod tests {
     fn enum_number() {
         enum_number! {
             #[derive(Copy, Clone, Debug, PartialEq, Eq, Deserialize, Serialize)]
-            #[serde(from = "u8", into = "u8")]
             pub enum T {
                 /// AAA
                 A = 1,

src/model/application/command.rs

@@ -230,7 +230,6 @@ enum_number! {
     /// [Discord docs](https://discord.com/developers/docs/interactions/application-commands#application-command-object-application-command-types).
     #[derive(Clone, Copy, Debug, Eq, Hash, Ord, PartialEq, PartialOrd, Deserialize, Serialize)]
     #[cfg_attr(feature = "typesize", derive(typesize::derive::TypeSize))]
-    #[serde(from = "u8", into = "u8")]
     #[non_exhaustive]
     pub enum CommandType {
         ChatInput = 1,
@@ -248,7 +247,6 @@ enum_number! {
     /// [Discord docs](https://discord.com/developers/docs/interactions/application-commands#application-command-object-entry-point-command-handler-types)
     #[derive(Clone, Copy, Debug, Eq, Hash, Ord, PartialEq, PartialOrd, Deserialize, Serialize)]
     #[cfg_attr(feature = "typesize", derive(typesize::derive::TypeSize))]
-    #[serde(from = "u8", into = "u8")]
     #[non_exhaustive]
     pub enum EntryPointHandlerType {
         AppHandler = 1,
@@ -323,7 +321,6 @@ enum_number! {
     /// [Discord docs](https://discord.com/developers/docs/interactions/application-commands#application-command-object-application-command-option-type).
     #[derive(Clone, Copy, Debug, Eq, Hash, Ord, PartialEq, PartialOrd, Deserialize, Serialize)]
     #[cfg_attr(feature = "typesize", derive(typesize::derive::TypeSize))]
-    #[serde(from = "u8", into = "u8")]
     #[non_exhaustive]
     pub enum CommandOptionType {
         SubCommand = 1,
@@ -396,7 +393,6 @@ enum_number! {
     /// [Discord docs](https://discord.com/developers/docs/interactions/application-commands#application-command-permissions-object-application-command-permission-type).
     #[derive(Clone, Copy, Debug, Eq, Hash, Ord, PartialEq, PartialOrd, Deserialize, Serialize)]
     #[cfg_attr(feature = "typesize", derive(typesize::derive::TypeSize))]
-    #[serde(from = "u8", into = "u8")]
     #[non_exhaustive]
     pub enum CommandPermissionType {
         Role = 1,

src/model/application/command_interaction.rs

@@ -574,7 +574,7 @@ fn option_from_raw(raw: RawCommandDataOption) -> Result<CommandDataOption> {
         CommandOptionType::Mentionable => CommandDataOptionValue::Mentionable(value!()),
         CommandOptionType::Role => CommandDataOptionValue::Role(value!()),
         CommandOptionType::User => CommandDataOptionValue::User(value!()),
-        CommandOptionType::Unknown(unknown) => CommandDataOptionValue::Unknown(unknown),
+        CommandOptionType(unknown) => CommandDataOptionValue::Unknown(unknown),
     };
 
     Ok(CommandDataOption {

src/model/application/component.rs

@@ -10,7 +10,6 @@ enum_number! {
     /// The type of a component
     #[derive(Clone, Copy, Debug, Eq, Hash, Ord, PartialEq, PartialOrd, Deserialize, Serialize)]
     #[cfg_attr(feature = "typesize", derive(typesize::derive::TypeSize))]
-    #[serde(from = "u8", into = "u8")]
     #[non_exhaustive]
     pub enum ComponentType {
         ActionRow = 1,
@@ -70,7 +69,7 @@ impl<'de> Deserialize<'de> for ActionRowComponent {
             ComponentType::ActionRow => {
                 return Err(DeError::custom("Invalid component type ActionRow"))
             },
-            ComponentType::Unknown(i) => {
+            ComponentType(i) => {
                 return Err(DeError::custom(format_args!("Unknown component type {i}")))
             },
         }
@@ -146,7 +145,7 @@ impl Serialize for ButtonKind {
                 custom_id,
                 style,
             } => Helper {
-                style: (*style).into(),
+                style: style.0,
                 url: None,
                 custom_id: Some(custom_id),
                 sku_id: None,
@@ -184,7 +183,6 @@ enum_number! {
     /// The style of a button.
     #[derive(Clone, Copy, Debug, Eq, Hash, Ord, PartialEq, PartialOrd, Deserialize, Serialize)]
     #[cfg_attr(feature = "typesize", derive(typesize::derive::TypeSize))]
-    #[serde(from = "u8", into = "u8")]
     #[non_exhaustive]
     pub enum ButtonStyle {
         Primary = 1,
@@ -298,7 +296,6 @@ enum_number! {
     /// [Discord docs](https://discord.com/developers/docs/interactions/message-components#text-inputs-text-input-styles).
     #[derive(Clone, Copy, Debug, Eq, Hash, Ord, PartialEq, PartialOrd, Deserialize, Serialize)]
     #[cfg_attr(feature = "typesize", derive(typesize::derive::TypeSize))]
-    #[serde(from = "u8", into = "u8")]
     #[non_exhaustive]
     pub enum InputTextStyle {
         Short = 1,

src/model/application/component_interaction.rs

@@ -285,12 +285,12 @@ impl<'de> Deserialize<'de> for ComponentInteractionDataKind {
             ComponentType::ChannelSelect => Self::ChannelSelect {
                 values: parse_values!(),
             },
-            ComponentType::Unknown(x) => Self::Unknown(x),
             x @ (ComponentType::ActionRow | ComponentType::InputText) => {
                 return Err(D::Error::custom(format_args!(
                     "invalid message component type in this context: {x:?}",
                 )));
             },
+            ComponentType(x) => Self::Unknown(x),
         })
     }
 }

src/model/application/interaction.rs

@@ -254,7 +254,7 @@ impl<'de> Deserialize<'de> for Interaction {
             InteractionType::Autocomplete => from_value(value).map(Interaction::Autocomplete),
             InteractionType::Modal => from_value(value).map(Interaction::Modal),
             InteractionType::Ping => from_value(value).map(Interaction::Ping),
-            InteractionType::Unknown(_) => return Err(DeError::custom("Unknown interaction type")),
+            InteractionType(_) => return Err(DeError::custom("Unknown interaction type")),
         }
         .map_err(DeError::custom)
     }
@@ -277,7 +277,6 @@ enum_number! {
     /// [Discord docs](https://discord.com/developers/docs/interactions/receiving-and-responding#interaction-object-interaction-type).
     #[derive(Clone, Copy, Debug, Eq, Hash, Ord, PartialEq, PartialOrd, Deserialize, Serialize)]
     #[cfg_attr(feature = "typesize", derive(typesize::derive::TypeSize))]
-    #[serde(from = "u8", into = "u8")]
     #[non_exhaustive]
     pub enum InteractionType {
         Ping = 1,
@@ -347,7 +346,7 @@ impl<'de> serde::Deserialize<'de> for AuthorizingIntegrationOwners {
                 let mut out = Vec::new();
                 while let Some(key_str) = map.next_key::<serde_cow::CowStr<'_>>()? {
                     let key_int = key_str.0.parse::<u8>().map_err(serde::de::Error::custom)?;
-                    let value = match InstallationContext::from(key_int) {
+                    let value = match InstallationContext(key_int) {
                         InstallationContext::Guild => {
                             // GuildId here can be `0`, which signals the command is guild installed
                             // but invoked in a DM, we have to do this fun deserialisation dance.
@@ -543,8 +542,8 @@ impl serde::Serialize for MessageInteractionMetadata {
             MessageInteractionMetadata::ModalSubmit(val) => {
                 serialize_with_type(serializer, val, InteractionType::Modal)
             },
-            &MessageInteractionMetadata::Unknown(kind) => {
-                tracing::warn!("Tried to serialize MessageInteractionMetadata::Unknown({}), serialising null instead", u8::from(kind));
+            &MessageInteractionMetadata::Unknown(InteractionType(kind)) => {
+                tracing::warn!("Tried to serialize MessageInteractionMetadata::Unknown({kind}), serialising null instead");
                 serializer.serialize_none()
             },
         }

src/model/application/mod.rs

@@ -106,7 +106,6 @@ enum_number! {
     /// [interaction contexts](https://discord.com/developers/docs/resources/application#application-object-application-integration-types).
     #[derive(Clone, Copy, Debug, Eq, Hash, Ord, PartialEq, PartialOrd, Deserialize, Serialize)]
     #[cfg_attr(feature = "typesize", derive(typesize::derive::TypeSize))]
-    #[serde(from = "u8", into = "u8")]
     #[non_exhaustive]
     pub enum InstallationContext {
         Guild = 0,
@@ -121,7 +120,6 @@ enum_number! {
     /// [interaction contexts](https://discord.com/developers/docs/interactions/receiving-and-responding#interaction-object-interaction-context-types).
     #[derive(Clone, Copy, Debug, Eq, Hash, Ord, PartialEq, PartialOrd, Deserialize, Serialize)]
     #[cfg_attr(feature = "typesize", derive(typesize::derive::TypeSize))]
-    #[serde(from = "u8", into = "u8")]
     #[non_exhaustive]
     pub enum InteractionContext {
         /// Interaction can be used within servers
@@ -184,7 +182,6 @@ pub struct TeamMember {
 enum_number! {
     /// [Discord docs](https://discord.com/developers/docs/topics/teams#data-models-membership-state-enum).
     #[derive(Clone, Copy, Debug, Eq, Hash, Ord, PartialEq, PartialOrd, Deserialize, Serialize)]
-    #[serde(from = "u8", into = "u8")]
     #[non_exhaustive]
     pub enum MembershipState {
         Invited = 1,

src/model/channel/guild_channel.rs

@@ -180,11 +180,9 @@ enum_number! {
     /// [Discord docs](https://discord.com/developers/docs/resources/channel#channel-object-forum-layout-types).
     #[derive(Clone, Copy, Debug, Default, Eq, Hash, Ord, PartialEq, PartialOrd, Deserialize, Serialize)]
     #[cfg_attr(feature = "typesize", derive(typesize::derive::TypeSize))]
-    #[serde(from = "u8", into = "u8")]
     #[non_exhaustive]
     pub enum ForumLayoutType {
         /// No default has been set for forum channel.
-        #[default]
         NotSet = 0,
         /// Display posts as a list.
         ListView = 1,

src/model/channel/message.rs

@@ -958,11 +958,9 @@ enum_number! {
     /// [Discord docs](https://discord.com/developers/docs/resources/channel#message-object-message-types).
     #[derive(Clone, Copy, Debug, Default, Eq, Hash, Ord, PartialEq, PartialOrd, Deserialize, Serialize)]
     #[cfg_attr(feature = "typesize", derive(typesize::derive::TypeSize))]
-    #[serde(from = "u8", into = "u8")]
     #[non_exhaustive]
     pub enum MessageType {
         /// A regular message.
-        #[default]
         Regular = 0,
         /// An indicator that a recipient was added by the author.
         GroupRecipientAddition = 1,
@@ -1029,7 +1027,6 @@ enum_number! {
     /// [Discord docs](https://discord.com/developers/docs/resources/channel#message-object-message-activity-types).
     #[derive(Clone, Copy, Debug, Eq, Hash, Ord, PartialEq, PartialOrd, Deserialize, Serialize)]
     #[cfg_attr(feature = "typesize", derive(typesize::derive::TypeSize))]
-    #[serde(from = "u8", into = "u8")]
     #[non_exhaustive]
     pub enum MessageActivityKind {
         Join = 1,
@@ -1078,12 +1075,11 @@ enum_number! {
     /// Message Reference Type information
     ///
     /// [Discord docs](https://discord.com/developers/docs/resources/message#message-reference-types)
-    #[derive(Clone, Copy, Debug, Default, Eq, Hash, Ord, PartialEq, PartialOrd, Deserialize, Serialize)]
+    #[derive(Clone, Copy, Debug, Eq, Hash, Ord, PartialEq, PartialOrd, Deserialize, Serialize)]
     #[cfg_attr(feature = "typesize", derive(typesize::derive::TypeSize))]
-    #[serde(from = "u8", into = "u8")]
     #[non_exhaustive]
+    #[<default> = 0]
     pub enum MessageReferenceKind {
-        #[default]
         Default = 0,
         Forward = 1,
         _ => Unknown(u8),
@@ -1421,12 +1417,11 @@ enum_number! {
     /// Currently, there is only the one option.
     ///
     /// [Discord docs](https://discord.com/developers/docs/resources/poll#layout-type)
-    #[derive(Clone, Copy, Debug, Default, Eq, Hash, Ord, PartialEq, PartialOrd, Deserialize, Serialize)]
+    #[derive(Clone, Copy, Debug, Eq, Hash, Ord, PartialEq, PartialOrd, Deserialize, Serialize)]
     #[cfg_attr(feature = "typesize", derive(typesize::derive::TypeSize))]
-    #[serde(from = "u8", into = "u8")]
     #[non_exhaustive]
+    #[<default> = 1]
     pub enum PollLayoutType {
-        #[default]
         Default = 1,
         _ => Unknown(u8),
     }

src/model/channel/mod.rs

@@ -214,11 +214,9 @@ enum_number! {
     /// [Discord docs](https://discord.com/developers/docs/resources/channel#channel-object-channel-types).
     #[derive(Clone, Copy, Debug, Default, Eq, Hash, Ord, PartialEq, PartialOrd, Deserialize, Serialize)]
     #[cfg_attr(feature = "typesize", derive(typesize::derive::TypeSize))]
-    #[serde(from = "u8", into = "u8")]
     #[non_exhaustive]
     pub enum ChannelType {
         /// An indicator that the channel is a text [`GuildChannel`].
-        #[default]
         Text = 0,
         /// An indicator that the channel is a [`PrivateChannel`].
         Private = 1,
@@ -252,8 +250,8 @@ enum_number! {
 
 impl ChannelType {
     #[must_use]
-    pub const fn name(&self) -> &str {
-        match *self {
+    pub const fn name(self) -> &'static str {
+        match self {
             Self::Private => "private",
             Self::Text => "text",
             Self::Voice => "voice",
@@ -266,7 +264,7 @@ impl ChannelType {
             Self::Stage => "stage",
             Self::Directory => "directory",
             Self::Forum => "forum",
-            Self::Unknown(_) => "unknown",
+            Self(_) => "unknown",
         }
     }
 }
@@ -359,7 +357,6 @@ enum_number! {
     /// [Discord docs](https://discord.com/developers/docs/resources/channel#channel-object-video-quality-modes).
     #[derive(Clone, Copy, Debug, Eq, Hash, Ord, PartialEq, PartialOrd, Deserialize, Serialize)]
     #[cfg_attr(feature = "typesize", derive(typesize::derive::TypeSize))]
-    #[serde(from = "u8", into = "u8")]
     #[non_exhaustive]
     pub enum VideoQualityMode {
         /// An indicator that the video quality is chosen by Discord for optimal
@@ -375,15 +372,14 @@ enum_number! {
     /// See [`StageInstance::privacy_level`].
     ///
     /// [Discord docs](https://discord.com/developers/docs/resources/stage-instance#stage-instance-object-privacy-level).
-    #[derive(Clone, Copy, Default, Debug, Eq, Hash, PartialEq, PartialOrd, Ord, Deserialize, Serialize)]
+    #[derive(Clone, Copy, Debug, Eq, Hash, PartialEq, PartialOrd, Ord, Deserialize, Serialize)]
     #[cfg_attr(feature = "typesize", derive(typesize::derive::TypeSize))]
-    #[serde(from = "u8", into = "u8")]
     #[non_exhaustive]
+    #[<default> = 2]
     pub enum StageInstancePrivacyLevel {
         /// The Stage instance is visible publicly. (deprecated)
         Public = 1,
         /// The Stage instance is visible to only guild members.
-        #[default]
         GuildOnly = 2,
         _ => Unknown(u8),
     }
@@ -395,7 +391,6 @@ enum_number! {
     /// [Discord docs](https://discord.com/developers/docs/resources/channel#thread-metadata-object)
     #[derive(Clone, Copy, Debug, Eq, Hash, PartialEq, PartialOrd, Ord, Deserialize, Serialize)]
     #[cfg_attr(feature = "typesize", derive(typesize::derive::TypeSize))]
-    #[serde(from = "u16", into = "u16")]
     #[non_exhaustive]
     pub enum AutoArchiveDuration {
         None = 0,
@@ -556,7 +551,6 @@ enum_number! {
     /// [Discord docs](https://discord.com/developers/docs/resources/channel#channel-object-sort-order-types).
     #[cfg_attr(feature = "typesize", derive(typesize::derive::TypeSize))]
     #[derive(Clone, Copy, Debug, Eq, Hash, PartialEq, PartialOrd, Ord, Deserialize, Serialize)]
-    #[serde(from = "u8", into = "u8")]
     #[non_exhaustive]
     pub enum SortOrder {
         /// Sort forum posts by activity.

src/model/channel/reaction.rs

@@ -63,7 +63,6 @@ enum_number! {
     /// A list of types a reaction can be.
     #[derive(Clone, Copy, Debug, Eq, Hash, Ord, PartialEq, PartialOrd, Deserialize, Serialize)]
     #[cfg_attr(feature = "typesize", derive(typesize::derive::TypeSize))]
-    #[serde(from = "u8", into = "u8")]
     #[non_exhaustive]
     pub enum ReactionTypes {
         Normal = 0,

src/model/connection.rs

@@ -42,7 +42,6 @@ enum_number! {
     ///
     /// [Discord docs](https://discord.com/developers/docs/resources/user#connection-object-visibility-types).
     #[derive(Clone, Copy, Debug, Eq, Hash, Ord, PartialEq, PartialOrd, Deserialize, Serialize)]
-    #[serde(from = "u8", into = "u8")]
     #[non_exhaustive]
     pub enum ConnectionVisibility {
         /// Invisible to everyone except the user themselves

src/model/gateway.rs

@@ -188,11 +188,9 @@ enum_number! {
     /// [Discord docs](https://discord.com/developers/docs/topics/gateway-events#activity-object-activity-types).
     #[derive(Clone, Copy, Debug, Default, Eq, Hash, Ord, PartialEq, PartialOrd, Deserialize, Serialize)]
     #[cfg_attr(feature = "typesize", derive(typesize::derive::TypeSize))]
-    #[serde(from = "u8", into = "u8")]
     #[non_exhaustive]
     pub enum ActivityType {
         /// An indicator that the user is playing a game.
-        #[default]
         Playing = 0,
         /// An indicator that the user is streaming to a service.
         Streaming = 1,