Use #[non_exhaustive] where applicable (#959)

src/builder/create_channel.rs

@@ -127,7 +127,6 @@ impl CreateChannel {
             let (id, kind) = match perm.kind {
                 PermissionOverwriteType::Member(id) => (id.0, "member"),
                 PermissionOverwriteType::Role(id) => (id.0, "role"),
-                PermissionOverwriteType::__Nonexhaustive => unreachable!(),
             };
 
             json!({

src/cache/mod.rs

@@ -101,6 +101,7 @@ impl<F: FromStr> FromStrAndCache for F {
 /// [`Shard`]: ../gateway/struct.Shard.html
 /// [`http`]: ../http/index.html
 #[derive(Debug)]
+#[non_exhaustive]
 pub struct Cache {
     /// A map of channels in [`Guild`]s that the current user has received data
     /// for.
@@ -182,7 +183,6 @@ pub struct Cache {
     pub(crate) message_queue: RwLock<HashMap<ChannelId, VecDeque<MessageId>>>,
     /// The settings for the cache.
     settings: RwLock<Settings>,
-    __nonexhaustive: (),
 }
 
 impl Cache {
@@ -969,7 +969,6 @@ impl Default for Cache {
             user: RwLock::new(CurrentUser::default()),
             users: RwLock::new(HashMap::default()),
             message_queue: RwLock::new(HashMap::default()),
-            __nonexhaustive: (),
         }
     }
 }

src/cache/settings.rs

@@ -11,19 +11,18 @@
 /// settings.max_messages(10);
 /// ```
 #[derive(Clone, Debug)]
+#[non_exhaustive]
 pub struct Settings {
     /// The maximum number of messages to store in a channel's message cache.
     ///
     /// Defaults to 0.
     pub max_messages: usize,
-    __nonexhaustive: (),
 }
 
 impl Default for Settings {
     fn default() -> Self {
         Settings {
             max_messages: usize::default(),
-            __nonexhaustive: (),
         }
     }
 }

src/client/bridge/gateway/shard_runner.rs

@@ -242,10 +242,8 @@ impl ShardRunner {
         match *action {
             ShardAction::Reconnect(ReconnectType::Reidentify) => self.request_restart().await,
             ShardAction::Reconnect(ReconnectType::Resume) => self.shard.resume().await,
-            ShardAction::Reconnect(ReconnectType::__Nonexhaustive) => unreachable!(),
             ShardAction::Heartbeat => self.shard.heartbeat().await,
             ShardAction::Identify => self.shard.identify().await,
-            ShardAction::__Nonexhaustive => unreachable!(),
         }
     }
 
@@ -427,7 +425,6 @@ impl ShardRunner {
                 // Value must be forwarded over the websocket
                 self.shard.client.send_json(&value).await.is_ok()
             },
-            InterMessage::__Nonexhaustive => unreachable!(),
         }
     }
 
@@ -545,7 +542,6 @@ impl ShardRunner {
                             return Ok((None, None, false));
                         }
                     },
-                    ReconnectType::__Nonexhaustive => unreachable!(),
                 }
 
                 return Ok((None, None, true));

src/client/dispatch.rs

@@ -65,11 +65,10 @@ fn context(
 
 // Once we can use `Box` as part of a pattern, we will reconsider boxing.
 #[allow(clippy::large_enum_variant)]
+#[non_exhaustive]
 pub(crate) enum DispatchEvent {
     Client(ClientEvent),
     Model(Event),
-    #[doc(hidden)]
-    __Nonexhaustive,
 }
 
 impl DispatchEvent {
@@ -138,8 +137,6 @@ impl DispatchEvent {
             Self::Model(Event::VoiceStateUpdate(ref mut event)) => {
                 update(cache_and_http, event).await;
             },
-            Self::Model(Event::__Nonexhaustive) => unreachable!(),
-            Self::__Nonexhaustive => unreachable!(),
             _ => (),
         }
     }
@@ -361,7 +358,6 @@ async fn handle_event(
                         event_handler.category_create(context, &channel).await;
                     });
                 },
-                Channel::__Nonexhaustive => unreachable!(),
             }
         },
         DispatchEvent::Model(Event::ChannelDelete(mut event)) => {
@@ -383,7 +379,6 @@ async fn handle_event(
                         event_handler.category_delete(context, &channel).await;
                     });
                 },
-                Channel::__Nonexhaustive => unreachable!(),
             }
         },
         DispatchEvent::Model(Event::ChannelPinsUpdate(event)) => {
@@ -745,7 +740,5 @@ async fn handle_event(
                 event_handler.webhook_update(context, event.guild_id, event.channel_id).await;
             });
         },
-        DispatchEvent::Model(Event::__Nonexhaustive) => unreachable!(),
-        DispatchEvent::__Nonexhaustive => unreachable!(),
     }
 }

src/client/error.rs

@@ -18,6 +18,7 @@ use std::{
 /// [`GuildId::ban`]: ../model/id/struct.GuildId.html#method.ban
 #[allow(clippy::enum_variant_names)]
 #[derive(Clone, Debug, Eq, Hash, PartialEq)]
+#[non_exhaustive]
 pub enum Error {
     /// When the token provided is invalid. This is returned when validating a
     /// token through the [`validate_token`] function.
@@ -30,8 +31,6 @@ pub enum Error {
     /// When all shards that the client is responsible for have shutdown with an
     /// error.
     Shutdown,
-    #[doc(hidden)]
-    __Nonexhaustive,
 }
 
 impl Display for Error {
@@ -40,7 +39,6 @@ impl Display for Error {
             Error::InvalidToken => f.write_str("The provided token was invalid"),
             Error::ShardBootFailure => f.write_str("Failed to (re-)boot a shard"),
             Error::Shutdown => f.write_str("The clients shards shutdown"),
-            Error::__Nonexhaustive => unreachable!(),
         }
     }
 }
@@ -51,7 +49,6 @@ impl StdError for Error {
             Error::InvalidToken => "The provided token was invalid",
             Error::ShardBootFailure => "Failed to (re-)boot a shard",
             Error::Shutdown => "The clients shards shutdown",
-            Error::__Nonexhaustive => unreachable!(),
         }
     }
 }

src/client/mod.rs

@@ -302,7 +302,6 @@ impl<'a> Future for ClientBuilder<'a> {
                 #[cfg(feature = "cache")]
                 update_cache_timeout: self.timeout.take(),
                 http: Arc::clone(&http),
-                __nonexhaustive: (),
             });
 
             self.fut = Some(Box::pin(async move {

src/constants.rs

@@ -65,6 +65,7 @@ pub static JOIN_MESSAGES: &[&str] = &[
 
 /// Enum to map gateway opcodes.
 #[derive(Clone, Copy, Debug, Eq, Hash, PartialEq, PartialOrd, Ord)]
+#[non_exhaustive]
 pub enum OpCode {
     /// Dispatches an event.
     Event = 0,
@@ -90,8 +91,6 @@ pub enum OpCode {
     Hello = 10,
     /// Sent immediately following a client heartbeat that was received.
     HeartbeatAck = 11,
-    #[doc(hidden)]
-    __Nonexhaustive,
 }
 
 enum_number!(
@@ -126,13 +125,13 @@ impl OpCode {
             OpCode::InvalidSession => 9,
             OpCode::Hello => 10,
             OpCode::HeartbeatAck => 11,
-            OpCode::__Nonexhaustive => unreachable!(),
         }
     }
 }
 
 /// Enum to map voice opcodes.
 #[derive(Clone, Copy, Debug, Eq, Hash, PartialEq, PartialOrd, Ord)]
+#[non_exhaustive]
 pub enum VoiceOpCode {
     /// Used to begin a voice websocket connection.
     Identify = 0,
@@ -158,8 +157,6 @@ pub enum VoiceOpCode {
     ClientConnect = 12,
     /// Message indicating that another user has disconnected from the voice channel.
     ClientDisconnect = 13,
-    #[doc(hidden)]
-    __Nonexhaustive,
 }
 
 enum_number!(
@@ -194,7 +191,6 @@ impl VoiceOpCode {
             VoiceOpCode::Resumed => 9,
             VoiceOpCode::ClientConnect => 12,
             VoiceOpCode::ClientDisconnect => 13,
-            VoiceOpCode::__Nonexhaustive => unreachable!(),
         }
     }
 }

src/error.rs

@@ -53,6 +53,7 @@ pub type Result<T> = StdResult<T, Error>;
 /// [`GatewayError`]: gateway/enum.GatewayError.html
 /// [`Result`]: type.Result.html
 #[derive(Debug)]
+#[non_exhaustive]
 pub enum Error {
     /// An error while decoding a payload.
     Decode(&'static str, Value),
@@ -109,8 +110,6 @@ pub enum Error {
     /// [voice module]: voice/index.html
     #[cfg(feature = "voice")]
     Voice(VoiceError),
-    #[doc(hidden)]
-    __Nonexhaustive,
 }
 
 impl From<FormatError> for Error {
@@ -198,7 +197,6 @@ impl Display for Error {
             Error::Tungstenite(inner) => fmt::Display::fmt(&inner, f),
             #[cfg(feature = "voice")]
             Error::Voice(_) => f.write_str("Voice error"),
-            Error::__Nonexhaustive => unreachable!(),
         }
     }
 }

src/framework/standard/args.rs

@@ -7,13 +7,12 @@ use std::borrow::Cow;
 
 /// Defines how an operation on an `Args` method failed.
 #[derive(Debug)]
+#[non_exhaustive]
 pub enum Error<E> {
     /// "END-OF-STRING". We reached the end. There's nothing to parse anymore.
     Eos,
     /// Parsing operation failed. Contains how it did.
     Parse(E),
-    #[doc(hidden)]
-    __Nonexhaustive,
 }
 
 impl<E> From<E> for Error<E> {
@@ -29,7 +28,6 @@ impl<E: fmt::Display> fmt::Display for Error<E> {
         match *self {
             Eos => write!(f, "ArgError(\"end of string\")"),
             Parse(ref e) => write!(f, "ArgError(\"{}\")", e),
-            __Nonexhaustive => unreachable!(),
         }
     }
 }

src/framework/standard/help_commands.rs

@@ -92,7 +92,6 @@ macro_rules! format_command_name {
             HelpBehaviour::Strike => format!("~~`{}`~~", $command_name),
             HelpBehaviour::Nothing => format!("`{}`", $command_name),
             HelpBehaviour::Hide => continue,
-            HelpBehaviour::__Nonexhaustive => unreachable!(),
         }
     };
 }
@@ -183,6 +182,7 @@ impl Suggestions {
 /// yields relevant data in customised textual
 /// representation.
 #[derive(Clone, Debug)]
+#[non_exhaustive]
 pub enum CustomisedHelpData<'a> {
     /// To display suggested commands.
     SuggestedCommands {
@@ -198,8 +198,6 @@ pub enum CustomisedHelpData<'a> {
     SingleCommand { command: Command<'a> },
     /// To display failure in finding a fitting command.
     NoCommandFound { help_error_message: &'a str },
-    #[doc(hidden)]
-    __Nonexhaustive,
 }
 
 /// Wraps around a `Vec<Vec<T>>` and provides access
@@ -1316,7 +1314,6 @@ pub async fn with_embeds(
             &command,
             help_options.embed_success_colour,
         ).await,
-        CustomisedHelpData::__Nonexhaustive => unreachable!(),
     };
 
     match response_result {
@@ -1491,7 +1488,6 @@ pub async fn plain(
         CustomisedHelpData::SingleCommand { ref command } => {
             single_command_to_plain_string(&help_options, &command)
         },
-        CustomisedHelpData::__Nonexhaustive => unreachable!(),
     };
 
     match msg.channel_id.say(&ctx, result).await {

src/framework/standard/mod.rs

@@ -47,6 +47,7 @@ use crate::model::{guild::Role, id::RoleId};
 /// An enum representing all possible fail conditions under which a command won't
 /// be executed.
 #[derive(Debug)]
+#[non_exhaustive]
 pub enum DispatchError {
     /// When a custom function check has failed.
     CheckFailed(&'static str, Reason),
@@ -82,8 +83,6 @@ pub enum DispatchError {
     IgnoredBot,
     /// When the bot ignores webhooks and a command was issued by one.
     WebhookAuthor,
-    #[doc(hidden)]
-    __Nonexhaustive,
 }
 
 type DispatchHook = for<'fut> fn(&'fut Context, &'fut Message, DispatchError) -> BoxFuture<'fut , ()>;

src/framework/standard/structures/check.rs

@@ -17,6 +17,7 @@ use futures::future::BoxFuture;
 /// [`Check`]: struct.Check.html
 /// [`CheckResult::Failure`]: enum.CheckResult.html#variant.Failure
 #[derive(Clone, Debug)]
+#[non_exhaustive]
 pub enum Reason {
     /// No information on the failure.
     Unknown,
@@ -26,8 +27,6 @@ pub enum Reason {
     Log(String),
     /// Information for the user but also for logging purposes.
     UserAndLog { user: String, log: String },
-    #[doc(hidden)]
-    __Nonexhaustive,
 }
 
 /// Returned from [`Check`]s.

src/framework/standard/structures/mod.rs

@@ -19,12 +19,11 @@ pub mod buckets;
 pub use self::check::*;
 
 #[derive(Debug, Clone, Copy, PartialEq, Eq)]
+#[non_exhaustive]
 pub enum OnlyIn {
     Dm,
     Guild,
     None,
-    #[doc(hidden)]
-    __Nonexhaustive,
 }
 
 impl Default for OnlyIn {
@@ -129,15 +128,14 @@ impl PartialEq for HelpCommand {
 /// Lacking required roles to execute the command.
 /// The command can't be used in the current channel (as in `DM only` or `guild only`).
 #[derive(Copy, Clone, Debug, PartialOrd, Ord, Eq, PartialEq)]
+#[non_exhaustive]
 pub enum HelpBehaviour {
     /// The command will be displayed, hence nothing will be done.
     Nothing,
     /// Strikes a command by applying `~~{command_name}~~`.
     Strike,
     /// Does not list a command in the help-menu.
     Hide,
-    #[doc(hidden)]
-    __Nonexhaustive,
 }
 
 #[derive(Clone, Debug, PartialEq)]

src/gateway/error.rs

@@ -13,6 +13,7 @@ use async_tungstenite::tungstenite::protocol::CloseFrame;
 /// Note that - from a user standpoint - there should be no situation in which
 /// you manually handle these.
 #[derive(Clone, Debug)]
+#[non_exhaustive]
 pub enum Error {
     /// There was an error building a URL.
     BuildingUrl,
@@ -57,8 +58,6 @@ pub enum Error {
     /// If an connection has been established but priviliged gateway intents
     /// were provided without enabling them prior.
     DisallowedGatewayIntents,
-    #[doc(hidden)]
-    __Nonexhaustive,
 }
 
 impl Display for Error {
@@ -78,7 +77,6 @@ impl Display for Error {
             Error::ReconnectFailure => f.write_str("Failed to Reconnect"),
             Error::InvalidGatewayIntents => f.write_str("Invalid gateway intents were provided"),
             Error::DisallowedGatewayIntents => f.write_str("Disallowed gateway intents were provided"),
-            Error::__Nonexhaustive => unreachable!(),
         }
     }
 }