refactor!: remove DecryptedMessage.has_epoch_changed

Author: SimonThormeyer

crypto-ffi/bindings/shared/src/commonTest/kotlin/com/wire/crypto/MLSTest.kt

@@ -188,7 +188,6 @@ class MLSTest : HasMockDeliveryService() {
         assertThat(decrypted.message).isNull()
         assertThat(decrypted.commitDelay).isNull()
         assertThat(decrypted.senderClientId).isNull()
-        assertThat(decrypted.hasEpochChanged).isTrue()
     }
 
     @Test

crypto-ffi/bindings/swift/WireCoreCrypto/WireCoreCryptoTests/WireCoreCryptoTests.swift

@@ -552,7 +552,6 @@ final class WireCoreCryptoTests: XCTestCase {
         XCTAssertNil(decrypted.message)
         XCTAssertNil(decrypted.commitDelay)
         XCTAssertNil(decrypted.senderClientId)
-        XCTAssertTrue(decrypted.hasEpochChanged)
     }
 
     // swiftlint:disable:next function_body_length

crypto-ffi/src/decrypted_message.rs

@@ -22,11 +22,6 @@ pub struct DecryptedMessage {
     pub commit_delay: Option<u64>,
     /// [ClientId] of the sender of the message being decrypted. Only present for application messages.
     pub sender_client_id: Option<Arc<ClientId>>,
-    /// true when the decrypted message resulted in an epoch change i.e. it was a commit
-    ///
-    /// Deprecated: this member will be removed in the future. Prefer using the `EpochObserver` interface.
-    #[deprecated = "This member will be removed in the future. Prefer using the `EpochObserver` interface."]
-    pub has_epoch_changed: bool,
     /// Identity claims present in the sender credential
     pub identity: WireIdentity,
     /// Only set when the decrypted message is a commit.
@@ -48,7 +43,6 @@ impl From<MlsConversationDecryptMessage> for DecryptedMessage {
             is_active: from.is_active,
             commit_delay: from.delay,
             sender_client_id: from.sender_client_id.map(Into::into).map(Arc::new),
-            has_epoch_changed: from.has_epoch_changed,
             identity: from.identity.into(),
             buffered_messages,
         }
@@ -70,11 +64,6 @@ pub struct BufferedDecryptedMessage {
     pub commit_delay: Option<u64>,
     /// [ClientId] of the sender of the message being decrypted. Only present for application messages.
     pub sender_client_id: Option<Arc<ClientId>>,
-    /// true when the decrypted message resulted in an epoch change i.e. it was a commit
-    ///
-    /// Deprecated: this member will be removed in the future. Prefer using the `EpochObserver` interface.
-    #[deprecated = "This member will be removed in the future. Prefer using the `EpochObserver` interface."]
-    pub has_epoch_changed: bool,
     /// Identity claims present in the sender credential
     pub identity: WireIdentity,
 }
@@ -87,7 +76,6 @@ impl From<MlsBufferedConversationDecryptMessage> for BufferedDecryptedMessage {
             is_active: from.is_active,
             commit_delay: from.delay,
             sender_client_id: from.sender_client_id.map(Into::into).map(Arc::new),
-            has_epoch_changed: from.has_epoch_changed,
             identity: from.identity.into(),
         }
     }

crypto/src/mls/conversation/conversation_guard/decrypt/mod.rs

@@ -60,9 +60,6 @@ pub struct MlsConversationDecryptMessage {
     pub delay: Option<u64>,
     /// [ClientId] of the sender of the message being decrypted. Only present for application messages.
     pub sender_client_id: Option<ClientId>,
-    /// Is the epoch changed after decrypting this message
-    #[deprecated = "This member will be removed in the future. Prefer using the `EpochObserver` interface."]
-    pub has_epoch_changed: bool,
     /// Identity claims present in the sender credential
     /// Present for all messages
     pub identity: WireIdentity,
@@ -88,25 +85,19 @@ pub struct MlsBufferedConversationDecryptMessage {
     /// see [MlsConversationDecryptMessage]
     pub sender_client_id: Option<ClientId>,
     /// see [MlsConversationDecryptMessage]
-    #[deprecated = "This member will be removed in the future. Prefer using the `EpochObserver` interface."]
-    pub has_epoch_changed: bool,
-    /// see [MlsConversationDecryptMessage]
     pub identity: WireIdentity,
     /// see [MlsConversationDecryptMessage]
     pub crl_new_distribution_points: NewCrlDistributionPoints,
 }
 
 impl From<MlsConversationDecryptMessage> for MlsBufferedConversationDecryptMessage {
     fn from(from: MlsConversationDecryptMessage) -> Self {
-        // we still support the `has_epoch_changed` field, though we'll remove it later
-        #[expect(deprecated)]
         Self {
             app_msg: from.app_msg,
             proposals: from.proposals,
             is_active: from.is_active,
             delay: from.delay,
             sender_client_id: from.sender_client_id,
-            has_epoch_changed: from.has_epoch_changed,
             identity: from.identity,
             crl_new_distribution_points: from.crl_new_distribution_points,
         }
@@ -237,15 +228,12 @@ impl ConversationGuard {
                     "Application message"
                 );
 
-                // we still support the `has_epoch_changed` field, though we'll remove it later
-                #[expect(deprecated)]
                 MlsConversationDecryptMessage {
                     app_msg: Some(app_msg.into_bytes()),
                     proposals: vec![],
                     is_active: true,
                     delay: None,
                     sender_client_id: Some(sender_client_id),
-                    has_epoch_changed: false,
                     identity,
                     buffered_messages: None,
                     crl_new_distribution_points: None.into(),
@@ -301,15 +289,12 @@ impl ConversationGuard {
                 let conversation = self.conversation().await;
                 let delay = conversation.compute_next_commit_delay();
 
-                // we still support the `has_epoch_changed` field, though we'll remove it later
-                #[expect(deprecated)]
                 MlsConversationDecryptMessage {
                     app_msg: None,
                     proposals: vec![],
                     is_active: true,
                     delay,
                     sender_client_id: None,
-                    has_epoch_changed: false,
                     identity,
                     buffered_messages: None,
                     crl_new_distribution_points,
@@ -411,15 +396,12 @@ impl ConversationGuard {
                 );
                 client.notify_epoch_changed(conversation.id.clone(), epoch).await;
 
-                // we still support the `has_epoch_changed` field, though we'll remove it later
-                #[expect(deprecated)]
                 MlsConversationDecryptMessage {
                     app_msg: None,
                     proposals,
                     is_active: conversation.group.is_active(),
                     delay: conversation.compute_next_commit_delay(),
                     sender_client_id: None,
-                    has_epoch_changed: true,
                     identity,
                     buffered_messages,
                     crl_new_distribution_points,
@@ -440,15 +422,12 @@ impl ConversationGuard {
                     .map_err(RecursiveError::mls_credential("getting new crl distribution points"))?;
                 conversation.group.store_pending_proposal(*proposal);
 
-                // we still support the `has_epoch_changed` field, though we'll remove it later
-                #[expect(deprecated)]
                 MlsConversationDecryptMessage {
                     app_msg: None,
                     proposals: vec![],
                     is_active: true,
                     delay: conversation.compute_next_commit_delay(),
                     sender_client_id: None,
-                    has_epoch_changed: false,
                     identity,
                     buffered_messages: None,
                     crl_new_distribution_points,

crypto/src/mls/conversation/own_commit.rs

@@ -114,15 +114,12 @@ impl MlsConversation {
         .await
         .map_err(RecursiveError::mls_credential("getting new crl distribution points"))?;
 
-        // we still support the `has_epoch_changed` field, though we'll remove it later
-        #[expect(deprecated)]
         Ok(MlsConversationDecryptMessage {
             app_msg: None,
             proposals: vec![],
             is_active: self.group.is_active(),
             delay: self.compute_next_commit_delay(),
             sender_client_id: None,
-            has_epoch_changed: true,
             identity,
             buffered_messages: None,
             crl_new_distribution_points,

crypto/src/mls/conversation/pending_conversation.rs

@@ -199,19 +199,12 @@ impl PendingConversation {
         .await
         .map_err(RecursiveError::mls_credential("getting new crl distribution points"))?;
 
-        // Note that though we return `has_epoch_changed: true` here, we don't notify the observer.
-        // This function can only be reached via a code path going through `MlsConversation::decrypt_message`
-        // which already notifies the observer; it would be redundant to notify here also.
-
-        // we still support the `has_epoch_changed` field, though we'll remove it later
-        #[expect(deprecated)]
         Ok(MlsConversationDecryptMessage {
             app_msg: None,
             proposals: vec![],
             is_active: conversation.group.is_active(),
             delay: conversation.compute_next_commit_delay(),
             sender_client_id: None,
-            has_epoch_changed: true,
             identity,
             buffered_messages,
             crl_new_distribution_points,