test(sequencer): add testing for cometbft block overflow in prepare p…

…roposal

crates/astria-sequencer/src/app.rs

@@ -2208,4 +2208,78 @@ mod test {
             },
         )
     }
+
+    #[tokio::test]
+    async fn app_prepare_proposal_cometbft_max_bytes_overflow_ok() {
+        let (mut app, storage) = initialize_app_with_storage(None, vec![]).await;
+
+        // update storage with initalized genesis app state
+        let intermediate_state = StateDelta::new(storage.latest_snapshot());
+        let state = Arc::try_unwrap(std::mem::replace(
+            &mut app.state,
+            Arc::new(intermediate_state),
+        ))
+        .expect("we have exclusive ownership of the State at commit()");
+        storage
+            .commit(state)
+            .await
+            .expect("applying genesis state should be okay");
+
+        // create txs which will cause cometbft overflow
+        let (alice_signing_key, _) = get_alice_signing_key_and_address();
+        let tx_pass = UnsignedTransaction {
+            nonce: 0,
+            actions: vec![
+                SequenceAction {
+                    rollup_id: RollupId::from([1u8; 32]),
+                    data: vec![1u8; 100_000],
+                    fee_asset_id: get_native_asset().id(),
+                }
+                .into(),
+            ],
+        }
+        .into_signed(&alice_signing_key);
+        let tx_overflow = UnsignedTransaction {
+            nonce: 1,
+            actions: vec![
+                SequenceAction {
+                    rollup_id: RollupId::from([1u8; 32]),
+                    data: vec![1u8; 100_000],
+                    fee_asset_id: get_native_asset().id(),
+                }
+                .into(),
+            ],
+        }
+        .into_signed(&alice_signing_key);
+
+        let txs: Vec<bytes::Bytes> = vec![
+            tx_pass.to_raw().encode_to_vec().into(),
+            tx_overflow.to_raw().encode_to_vec().into(),
+        ];
+
+        // send to prepare_proposal
+        let prepare_args = abci::request::PrepareProposal {
+            max_tx_bytes: 200_200,
+            txs,
+            local_last_commit: None,
+            misbehavior: vec![],
+            height: Height::default(),
+            time: Time::now(),
+            next_validators_hash: Hash::default(),
+            proposer_address: account::Id::new([1u8; 20]),
+        };
+
+        let result = app
+            .prepare_proposal(prepare_args, storage)
+            .await
+            .expect("too large transactions should not cause prepare proposal to fail");
+
+        // see only first tx made it in
+        assert_eq!(
+            result.txs.len(),
+            3,
+            "total transaciton length should be three, including the two commitments and the one \
+             tx that fit"
+        );
+    }
 }