refactor(sdk-ui): remove expect() with better borrow (#6513)

<!-- description of the changes in this PR -->

Follow up on review on this PR
https://github.com/matrix-org/matrix-rust-sdk/pull/6494#discussion_r3146315397

Remove the usage of if/expect that was introduced because of a borrowing
problem.
Instead we use `ok_or_else`, but we clone the debug_string early (to
avoid needing to borrow event again in the `ok_or_else`), it is not
ideal either but better that the expect/panic

I also removed the `is_rtc_notification` and `is_live_location` that was
created I believe just to avoid the borrowing problem? They were only
used in test and it just a shortcut for `matches!()`

- [ ] I've documented the public API Changes in the appropriate
`CHANGELOG.md` files.
- [ ] This PR was made with the help of AI.

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<!-- See CONTRIBUTING.md if you don't know what this is -->
Signed-off-by:

crates/matrix-sdk-ui/src/timeline/controller/aggregations.rs

@@ -39,7 +39,6 @@
 
 use std::{borrow::Cow, collections::HashMap, sync::Arc};
 
-use as_variant::as_variant;
 use matrix_sdk::{check_validity_of_replacement_events, deserialized_responses::EncryptionInfo};
 use ruma::{
     MilliSecondsSinceUnixEpoch, OwnedEventId, OwnedTransactionId, OwnedUserId,
@@ -183,18 +182,16 @@ pub(crate) struct Aggregation {
 fn poll_state_from_item<'a>(
     event: &'a mut Cow<'_, EventTimelineItem>,
 ) -> Result<&'a mut PollState, AggregationError> {
-    if event.content().is_poll() {
-        // It was a poll! Now return the state as mutable.
-        let state = as_variant!(
-            event.to_mut().content_mut(),
-            TimelineItemContent::MsgLike(MsgLikeContent { kind: MsgLikeKind::Poll(s), ..}) => s
-        )
-        .expect("it was a poll just above");
+    let content = event.to_mut().content_mut();
+
+    if let TimelineItemContent::MsgLike(MsgLikeContent { kind: MsgLikeKind::Poll(state), .. }) =
+        content
+    {
         Ok(state)
     } else {
         Err(AggregationError::InvalidType {
             expected: "a poll".to_owned(),
-            actual: event.content().debug_string().to_owned(),
+            actual: content.debug_string().to_owned(),
         })
     }
 }
@@ -203,18 +200,18 @@ fn poll_state_from_item<'a>(
 fn live_location_state_from_item<'a>(
     event: &'a mut Cow<'_, EventTimelineItem>,
 ) -> Result<&'a mut LiveLocationState, AggregationError> {
-    if event.content().is_live_location() {
-        // It was a live location! Now return the state as mutable.
-        let state = event
-            .to_mut()
-            .content_mut()
-            .as_live_location_state_mut()
-            .expect("it was a live location just above");
+    let content = event.to_mut().content_mut();
+
+    if let TimelineItemContent::MsgLike(MsgLikeContent {
+        kind: MsgLikeKind::LiveLocation(state),
+        ..
+    }) = content
+    {
         Ok(state)
     } else {
         Err(AggregationError::InvalidType {
             expected: "a live location".to_owned(),
-            actual: event.content().debug_string().to_owned(),
+            actual: content.debug_string().to_owned(),
         })
     }
 }
@@ -223,13 +220,16 @@ fn live_location_state_from_item<'a>(
 fn rtc_notification_declinations_from_item<'a>(
     event: &'a mut Cow<'_, EventTimelineItem>,
 ) -> Result<&'a mut Vec<OwnedUserId>, AggregationError> {
-    let debug_string = event.content().debug_string().to_owned();
-    event.to_mut().content_mut().as_rtc_notification_mut().ok_or_else(|| {
-        AggregationError::InvalidType {
+    let content = event.to_mut().content_mut();
+
+    if let TimelineItemContent::RtcNotification { declined_by, .. } = content {
+        Ok(declined_by)
+    } else {
+        Err(AggregationError::InvalidType {
             expected: "an rtc notification".to_owned(),
-            actual: debug_string,
-        }
-    })
+            actual: content.debug_string().to_owned(),
+        })
+    }
 }
 
 impl Aggregation {

crates/matrix-sdk-ui/src/timeline/event_item/content/mod.rs

@@ -223,38 +223,6 @@ impl TimelineItemContent {
         }) => state)
     }
 
-    /// If `self` is of the [`MsgLike`][Self::MsgLike] variant with a
-    /// [`LiveLocation`][MsgLikeKind::LiveLocation] kind, return the inner
-    /// [`LiveLocationState`] mutably.
-    pub(in crate::timeline) fn as_live_location_state_mut(
-        &mut self,
-    ) -> Option<&mut LiveLocationState> {
-        as_variant!(self, Self::MsgLike(MsgLikeContent {
-            kind: MsgLikeKind::LiveLocation(state),
-            ..
-        }) => state)
-    }
-
-    pub(in crate::timeline) fn as_rtc_notification_mut(&mut self) -> Option<&mut Vec<OwnedUserId>> {
-        if let TimelineItemContent::RtcNotification { declined_by, .. } = self {
-            Some(declined_by)
-        } else {
-            None
-        }
-    }
-
-    /// Check whether this item's content is a
-    /// [`LiveLocation`][MsgLikeKind::LiveLocation].
-    pub fn is_live_location(&self) -> bool {
-        matches!(self, Self::MsgLike(MsgLikeContent { kind: MsgLikeKind::LiveLocation(_), .. }))
-    }
-
-    /// Check whether this item's content is an
-    /// [`RtcNotification`][Self::RtcNotification].
-    pub fn is_rtc_notification(&self) -> bool {
-        matches!(self, Self::RtcNotification { .. })
-    }
-
     /// If `self` is of the [`MsgLike`][Self::MsgLike] variant, return the
     /// inner [`Message`].
     pub fn as_message(&self) -> Option<&Message> {

crates/matrix-sdk-ui/src/timeline/tests/shields.rs

@@ -22,7 +22,8 @@ use ruma::{
 use stream_assert::{assert_next_matches, assert_pending};
 
 use crate::timeline::{
-    EventSendState, TimelineEventShieldState, TimelineEventShieldStateCode,
+    EventSendState, MsgLikeContent, MsgLikeKind, TimelineEventShieldState,
+    TimelineEventShieldStateCode, TimelineItemContent,
     tests::{TestTimeline, TestTimelineBuilder},
 };
 
@@ -156,7 +157,13 @@ async fn test_live_location_no_sent_in_clear_shield() {
 
     // No beacons yet → shield should be None.
     let item = assert_next_matches!(stream, VectorDiff::PushBack { value } => value);
-    assert!(item.content().is_live_location(), "timeline item should be a live location");
+    assert!(
+        matches!(
+            item.content(),
+            TimelineItemContent::MsgLike(MsgLikeContent { kind: MsgLikeKind::LiveLocation(_), .. })
+        ),
+        "timeline item should be a live location"
+    );
 
     let shield = item.get_shield(false);
     assert_eq!(shield, TimelineEventShieldState::None);

crates/matrix-sdk-ui/tests/integration/timeline/rtc.rs

@@ -52,7 +52,7 @@ async fn test_decline_call() {
 
     assert_let!(VectorDiff::PushBack { value: message } = &timeline_updates[0]);
     let event_item = message.as_event().unwrap();
-    assert!(event_item.content().is_rtc_notification());
+    assert!(matches!(event_item.content(), TimelineItemContent::RtcNotification { .. }));
     assert_let!(
         TimelineItemContent::RtcNotification { call_intent: _, declined_by } = event_item.content()
     );
@@ -116,7 +116,7 @@ async fn test_multiple_decline_call() {
 
     assert_let!(VectorDiff::PushBack { value: message } = &timeline_updates[0]);
     let event_item = message.as_event().unwrap();
-    assert!(event_item.content().is_rtc_notification());
+    assert!(matches!(event_item.content(), TimelineItemContent::RtcNotification { .. }));
     assert_let!(
         TimelineItemContent::RtcNotification { call_intent: _, declined_by } = event_item.content()
     );