test(twap-monitor): cover a removal arriving before its create

modules/twap-monitor/src/keeper.rs

@@ -1195,6 +1195,64 @@ mod tests {
         });
     }
 
+    #[test]
+    fn removal_before_its_create_self_heals_via_the_first_poll() {
+        // The exact race module.toml's own comment warns about: the two
+        // log streams merge in arrival order, not chain order, so a
+        // removal can reach `on_chain_logs` before the create it
+        // cancels. `removal_of_an_unindexed_watch_is_a_no_op` already
+        // confirms the removal alone is silently dropped in that case -
+        // this chains the rest of the story: the create that follows
+        // persists the watch anyway, with no memory of the earlier
+        // removal, and the very first poll must still tear it down.
+        //
+        // The revert used here is `SingleOrderNotAuthed()` - the actual
+        // selector the deployed `ComposableCow._auth` reverts with for a
+        // removed order (nullislabs/composable-cow/src/ComposableCow.sol),
+        // not one of the five legacy `IConditionalOrder` reasons
+        // `poll_invalid_drops_watch_and_gates` already covers.
+        // `LegacyRevertAdapter::classify`'s unrecognised-selector
+        // fallback is what has to catch this one.
+        let host = MockHost::new();
+        let venue = MockVenue::default();
+        let owner = address!("0011223344556677889900AABBCCDDEEFF001122");
+        let params = sample_params();
+        let hash = keccak256(params.abi_encode());
+        let key = watch_key(&owner, &hash);
+
+        on_chain_logs(&host, &[make_removed_log(owner, hash, at(2, 0))]).unwrap();
+        assert_eq!(
+            host.store.len(),
+            0,
+            "removal of an unindexed watch is a no-op"
+        );
+
+        on_chain_logs(&host, &[make_log(owner, &params, at(1, 0))]).unwrap();
+        assert!(
+            host.store.snapshot().contains_key(&key),
+            "the create persists the watch with no memory of the earlier removal",
+        );
+
+        let selector = alloy_primitives::keccak256(b"SingleOrderNotAuthed()")[..4].to_vec();
+        host.chain.respond_to(
+            "eth_call",
+            programmed_eth_call_params(owner, &params),
+            Err(ChainError::Rpc(nexum_sdk::host::RpcError {
+                code: 3,
+                message: "execution reverted".into(),
+                data: Some(selector.into()),
+            })),
+        );
+
+        dispatch(&host, &venue, sample_block(1_000)).unwrap();
+
+        assert!(
+            !host.store.snapshot().contains_key(&key),
+            "the first poll against a chain-dead order must self-heal the stale watch",
+        );
+        assert_eq!(venue.submit_count(), 0, "a dead order is never submitted");
+    }
+
     /// The supervisor builds log filters from this manifest's chain-log
     /// `event_signature` pins, so a drift from a decoder topic-0
     /// subscribes to one topic and decodes another. Compares the two