test: Don't leave protected group if some member's key is missing (#5508)

The "I left the group" message can't be sent to a protected group if some member's key is missing,
in this case we should remain in the group. The problem should be fixed first, then the user may
retry to leave the group.

src/receive_imf/tests.rs

@@ -13,7 +13,7 @@ use crate::constants::{DC_GCL_FOR_FORWARDING, DC_GCL_NO_SPECIALS};
 use crate::download::MIN_DOWNLOAD_LIMIT;
 use crate::imap::prefetch_should_download;
 use crate::imex::{imex, ImexMode};
-use crate::test_utils::{get_chat_msg, TestContext, TestContextManager};
+use crate::test_utils::{get_chat_msg, mark_as_verified, TestContext, TestContextManager};
 use crate::tools::SystemTime;
 
 #[tokio::test(flavor = "multi_thread", worker_threads = 2)]
@@ -4464,6 +4464,40 @@ Chat-Group-Member-Added: charlie@example.com",
     Ok(())
 }
 
+#[tokio::test(flavor = "multi_thread", worker_threads = 2)]
+async fn test_leave_protected_group_missing_member_key() -> Result<()> {
+    let mut tcm = TestContextManager::new();
+    let alice = &tcm.alice().await;
+    let bob = &tcm.bob().await;
+    mark_as_verified(alice, bob).await;
+    let alice_bob_id = alice.add_or_lookup_contact(bob).await.id;
+    let group_id = create_group_chat(alice, ProtectionStatus::Protected, "Group").await?;
+    add_contact_to_chat(alice, group_id, alice_bob_id).await?;
+    alice.send_text(group_id, "Hello!").await;
+    alice
+        .sql
+        .execute(
+            "UPDATE acpeerstates SET addr=? WHERE addr=?",
+            ("b@b", "bob@example.net"),
+        )
+        .await?;
+    assert!(remove_contact_from_chat(alice, group_id, ContactId::SELF)
+        .await
+        .is_err());
+    assert!(is_contact_in_chat(alice, group_id, ContactId::SELF).await?);
+    alice
+        .sql
+        .execute(
+            "UPDATE acpeerstates SET addr=? WHERE addr=?",
+            ("bob@example.net", "b@b"),
+        )
+        .await?;
+    remove_contact_from_chat(alice, group_id, ContactId::SELF).await?;
+    alice.pop_sent_msg().await;
+    assert!(!is_contact_in_chat(alice, group_id, ContactId::SELF).await?);
+    Ok(())
+}
+
 #[tokio::test(flavor = "multi_thread", worker_threads = 2)]
 async fn test_forged_from() -> Result<()> {
     let mut tcm = TestContextManager::new();