events: Remove EventKind

The EventType associated type on EventContent practically provides the
same information.

crates/ruma-common/src/events.rs

@@ -21,7 +21,7 @@
 //! # Extending Ruma with custom events
 //!
 //! For our examples we will start with a simple custom state event. `ruma_event`
-//! specifies the state event's `type` and it's [`kind`](EventKind).
+//! specifies the state event's `type` and its `kind`.
 //!
 //! ```rust
 //! use ruma_common::events::macros::EventContent;

crates/ruma-common/src/events/content.rs

@@ -34,61 +34,12 @@ where
     }
 }
 
-/// Trait for abstracting over event content structs.
-///
-/// … but *not* enums which don't always have an event type and kind (e.g. message vs state) that's
-/// fixed / known at compile time.
+/// An event content type with a statically-known event `type` value.
 pub trait StaticEventContent: EventContent {
-    /// The event's "kind".
-    ///
-    /// See the type's documentation.
-    const KIND: EventKind;
-
     /// The event type.
     const TYPE: &'static str;
 }
 
-/// The "kind" of an event.
-///
-/// This corresponds directly to the event content marker traits.
-#[derive(Clone, Copy, Debug, PartialEq, Eq, PartialOrd, Ord, Hash)]
-#[non_exhaustive]
-pub enum EventKind {
-    /// Global account data event kind.
-    GlobalAccountData,
-
-    /// Room account data event kind.
-    RoomAccountData,
-
-    /// Ephemeral room event kind.
-    EphemeralRoomData,
-
-    /// Message-like event kind.
-    ///
-    /// Since redacted / non-redacted message-like events are used in the same places but have
-    /// different sets of fields, these two variations are treated as two closely-related event
-    /// kinds.
-    MessageLike {
-        /// Redacted variation?
-        redacted: bool,
-    },
-
-    /// State event kind.
-    ///
-    /// Since redacted / non-redacted state events are used in the same places but have different
-    /// sets of fields, these two variations are treated as two closely-related event kinds.
-    State {
-        /// Redacted variation?
-        redacted: bool,
-    },
-
-    /// To-device event kind.
-    ToDevice,
-
-    /// Presence event kind.
-    Presence,
-}
-
 /// Content of a global account-data event.
 pub trait GlobalAccountDataEventContent:
     EventContent<EventType = GlobalAccountDataEventType>

crates/ruma-common/src/events/presence.rs

@@ -6,7 +6,7 @@ use js_int::UInt;
 use ruma_macros::{Event, EventContent};
 use serde::{ser::SerializeStruct, Deserialize, Serialize};
 
-use super::{EventContent, EventKind, StaticEventContent};
+use super::EventContent;
 use crate::{presence::PresenceState, OwnedMxcUri, OwnedUserId};
 
 /// Presence event.
@@ -85,11 +85,6 @@ impl PresenceEventContent {
     }
 }
 
-impl StaticEventContent for PresenceEventContent {
-    const KIND: EventKind = EventKind::Presence;
-    const TYPE: &'static str = "m.presence";
-}
-
 #[cfg(test)]
 mod tests {
     use js_int::uint;

crates/ruma-macros/src/events/event_content.rs

@@ -357,8 +357,8 @@ pub fn expand_event_content(
         true,
     )
     .unwrap_or_else(syn::Error::into_compile_error);
-    let static_event_content_impl = event_kind
-        .map(|k| generate_static_event_content_impl(ident, k, false, &event_type, ruma_common));
+    let static_event_content_impl =
+        generate_static_event_content_impl(ident, &event_type, ruma_common);
     let type_aliases = event_kind.map(|k| {
         generate_event_type_aliases(k, ident, &event_type.value(), ruma_common)
             .unwrap_or_else(syn::Error::into_compile_error)
@@ -453,13 +453,8 @@ fn generate_redacted_event_content<'a>(
 
     let sub_trait_name = format_ident!("Redacted{event_kind}Content");
 
-    let static_event_content_impl = generate_static_event_content_impl(
-        &redacted_ident,
-        event_kind,
-        true,
-        event_type,
-        ruma_common,
-    );
+    let static_event_content_impl =
+        generate_static_event_content_impl(&redacted_ident, event_type, ruma_common);
 
     Ok(quote! {
         // this is the non redacted event content's impl
@@ -613,13 +608,8 @@ fn generate_possibly_redacted_event_content<'a>(
         )
         .unwrap_or_else(syn::Error::into_compile_error);
 
-        let static_event_content_impl = generate_static_event_content_impl(
-            &possibly_redacted_ident,
-            event_kind,
-            true,
-            event_type,
-            ruma_common,
-        );
+        let static_event_content_impl =
+            generate_static_event_content_impl(&possibly_redacted_ident, event_type, ruma_common);
 
         Ok(quote! {
             #[doc = #doc]
@@ -961,30 +951,11 @@ fn generate_event_content_impl<'a>(
 
 fn generate_static_event_content_impl(
     ident: &Ident,
-    event_kind: EventKind,
-    redacted: bool,
     event_type: &LitStr,
     ruma_common: &TokenStream,
 ) -> TokenStream {
-    let event_kind = match event_kind {
-        EventKind::GlobalAccountData => quote! { GlobalAccountData },
-        EventKind::RoomAccountData => quote! { RoomAccountData },
-        EventKind::Ephemeral => quote! { EphemeralRoomData },
-        EventKind::MessageLike => quote! { MessageLike { redacted: #redacted } },
-        EventKind::State => quote! { State { redacted: #redacted } },
-        EventKind::ToDevice => quote! { ToDevice },
-        EventKind::RoomRedaction
-        | EventKind::Presence
-        | EventKind::Decrypted
-        | EventKind::HierarchySpaceChild => {
-            unreachable!("not a valid event content kind")
-        }
-    };
-
     quote! {
         impl #ruma_common::events::StaticEventContent for #ident {
-            const KIND: #ruma_common::events::EventKind =
-                #ruma_common::events::EventKind::#event_kind;
             const TYPE: &'static ::std::primitive::str = #event_type;
         }
     }