fix(model): Deserialize unavailable guilds in GUILD_CREATE.

This changes GuildCreate from being a tuple struct to being a enum
that can either be available or unavailable, and containing either a
full Guild or a UnavailableGuild.

examples/gateway-request-members.rs

@@ -22,7 +22,7 @@ async fn main() -> anyhow::Result<()> {
         match event {
             Event::GuildCreate(guild) => {
                 // Let's request all of the guild's members for caching.
-                shard.command(&RequestGuildMembers::builder(guild.id).query("", None));
+                shard.command(&RequestGuildMembers::builder(guild.id()).query("", None));
             }
             Event::Ready(_) => {
                 // You can also specify an individual member within a guild.

twilight-cache-inmemory/src/event/guild.rs

@@ -136,7 +136,12 @@ impl<CacheModels: CacheableModels> InMemoryCache<CacheModels> {
 
 impl<CacheModels: CacheableModels> UpdateCache<CacheModels> for GuildCreate {
     fn update(&self, cache: &InMemoryCache<CacheModels>) {
-        cache.cache_guild(self.0.clone());
+        match self {
+            GuildCreate::Available(g) => cache.cache_guild(g.clone()),
+            GuildCreate::Unavailable(g) => {
+                cache.unavailable_guilds.insert(g.id);
+            }
+        }
     }
 }
 
@@ -350,7 +355,7 @@ mod tests {
         let cache = DefaultInMemoryCache::new();
         let guild = test::guild(Id::new(1), None);
 
-        cache.update(&GuildCreate(guild.clone()));
+        cache.update(&GuildCreate::Availible(guild.clone()));
 
         let mutation = PartialGuild {
             id: guild.id,
@@ -406,7 +411,7 @@ mod tests {
         let member = test::member(user_id);
         let guild = test::guild(guild_id, Some(1));
 
-        cache.update(&GuildCreate(guild));
+        cache.update(&GuildCreate::Availible(guild));
         cache.update(&MemberAdd { guild_id, member });
 
         assert_eq!(cache.guild(guild_id).unwrap().member_count, Some(2));
@@ -425,7 +430,7 @@ mod tests {
         let mut guild = test::guild(guild_id, Some(1));
         guild.members.push(member);
 
-        cache.update(&GuildCreate(guild.clone()));
+        cache.update(&GuildCreate::Availible(guild.clone()));
 
         assert_eq!(
             1,
@@ -446,7 +451,7 @@ mod tests {
         );
         assert!(cache.guild(guild_id).unwrap().unavailable);
 
-        cache.update(&GuildCreate(guild));
+        cache.update(&GuildCreate::Availible(guild));
 
         assert_eq!(
             1,

twilight-cache-inmemory/src/permission.rs

@@ -923,7 +923,7 @@ mod tests {
         let cache = DefaultInMemoryCache::new();
         let permissions = cache.permissions();
 
-        cache.update(&GuildCreate(base_guild()));
+        cache.update(&GuildCreate::Availible(base_guild()));
         cache.update(&MemberAdd {
             guild_id: GUILD_ID,
             member: test::member(USER_ID),
@@ -969,7 +969,7 @@ mod tests {
         let cache = DefaultInMemoryCache::new();
         let permissions = cache.permissions();
 
-        cache.update(&GuildCreate(base_guild()));
+        cache.update(&GuildCreate::Availible(base_guild()));
         assert!(matches!(
             permissions.in_channel(USER_ID, CHANNEL_ID).unwrap_err().kind(),
             ChannelErrorType::ChannelUnavailable { channel_id: c_id }
@@ -1030,7 +1030,7 @@ mod tests {
     fn owner() -> Result<(), Box<dyn Error>> {
         let cache = DefaultInMemoryCache::new();
         let permissions = cache.permissions();
-        cache.update(&GuildCreate(base_guild()));
+        cache.update(&GuildCreate::Availible(base_guild()));
 
         assert!(permissions.root(OWNER_ID, GUILD_ID)?.is_all());
 
@@ -1088,7 +1088,7 @@ mod tests {
             everyone_permissions,
         )]);
 
-        cache.update(&GuildCreate(guild));
+        cache.update(&GuildCreate::Availible(guild));
         let mut member = test::member(USER_ID);
         member.communication_disabled_until = Some(in_future);
         cache.update(&MemberAdd {

twilight-model/src/gateway/event/mod.rs

@@ -183,7 +183,7 @@ impl Event {
             Event::ChannelUpdate(e) => e.0.guild_id,
             Event::CommandPermissionsUpdate(e) => Some(e.0.guild_id),
             Event::GuildAuditLogEntryCreate(e) => e.0.guild_id,
-            Event::GuildCreate(e) => Some(e.0.id),
+            Event::GuildCreate(e) => Some(e.id()),
             Event::GuildDelete(e) => Some(e.id),
             Event::GuildEmojisUpdate(e) => Some(e.guild_id),
             Event::GuildIntegrationsUpdate(e) => Some(e.guild_id),

twilight-model/src/gateway/payload/incoming/guild_create.rs

@@ -1,20 +1,60 @@
-use crate::guild::Guild;
+use crate::{
+    guild::{Guild, UnavailableGuild},
+    id::{marker::GuildMarker, Id},
+};
 use serde::{Deserialize, Serialize};
-use std::ops::{Deref, DerefMut};
 
 #[derive(Clone, Debug, Deserialize, Eq, PartialEq, Serialize)]
-pub struct GuildCreate(pub Guild);
-
-impl Deref for GuildCreate {
-    type Target = Guild;
+#[serde(untagged)]
+pub enum GuildCreate {
+    Available(Guild),
+    Unavailable(UnavailableGuild),
+}
 
-    fn deref(&self) -> &Self::Target {
-        &self.0
+impl GuildCreate {
+    /// Extract guild id.
+    pub const fn id(&self) -> Id<GuildMarker> {
+        match self {
+            GuildCreate::Available(g) => g.id,
+            GuildCreate::Unavailable(g) => g.id,
+        }
     }
 }
 
-impl DerefMut for GuildCreate {
-    fn deref_mut(&mut self) -> &mut Self::Target {
-        &mut self.0
+#[cfg(test)]
+mod tests {
+    use serde_test::Token;
+
+    use crate::{guild::UnavailableGuild, id::Id};
+
+    use super::GuildCreate;
+
+    #[test]
+    fn unavailable_guild() {
+        let expected = GuildCreate::Unavailable(UnavailableGuild {
+            id: Id::new(1234),
+            unavailable: true,
+        });
+
+        // Note: This looks a bit strange because it does not use
+        //       Token::TupleVariant, this is because it will
+        //       serialize back into a struct, and thus make it
+        //       fails. This also tests that the enum is transparent
+        //       for serde.
+        serde_test::assert_tokens(
+            &expected,
+            &[
+                Token::Struct {
+                    name: "UnavailableGuild",
+                    len: 2,
+                },
+                Token::Str("id"),
+                Token::NewtypeStruct { name: "Id" },
+                Token::Str("1234"),
+                Token::Str("unavailable"),
+                Token::Bool(true),
+                Token::StructEnd,
+            ],
+        );
     }
 }