From a21dd26a5ebb5879bbb2c81821520550554527b9 Mon Sep 17 00:00:00 2001
From: teor <teor@riseup.net>
Date: Thu, 14 Oct 2021 23:19:21 +1000
Subject: [PATCH] Insert new mempool transactions, then check for rejections
 (#2874)

Previously, we checked some rejections before inserting,
so we could accept some new transactions that should be rejected.
---
 zebrad/src/components/mempool.rs | 37 ++++++++++++++++----------------
 1 file changed, 19 insertions(+), 18 deletions(-)

diff --git a/zebrad/src/components/mempool.rs b/zebrad/src/components/mempool.rs
index 94bcba90..01f11759 100644
--- a/zebrad/src/components/mempool.rs
+++ b/zebrad/src/components/mempool.rs
@@ -267,24 +267,6 @@ impl Service<Request> for Mempool {
                 storage,
                 tx_downloads,
             } => {
-                if let Some(tip_action) = self.chain_tip_change.last_tip_change() {
-                    match tip_action {
-                        // Clear the mempool and cancel downloads if there has been a chain tip reset.
-                        TipAction::Reset { .. } => {
-                            storage.clear();
-                            tx_downloads.cancel_all();
-                        }
-                        // Cancel downloads/verifications/storage of transactions
-                        // with the same mined IDs as recently mined transactions.
-                        TipAction::Grow { block } => {
-                            let mined_ids = block.transaction_hashes.iter().cloned().collect();
-                            tx_downloads.cancel(&mined_ids);
-                            storage.remove_same_effects(&mined_ids);
-                            storage.clear_tip_rejections();
-                        }
-                    }
-                }
-
                 // Collect inserted transaction ids.
                 let mut send_to_peers_ids = HashSet::<_>::new();
 
@@ -304,6 +286,25 @@ impl Service<Request> for Mempool {
                     };
                 }
 
+                // Handle best chain tip changes
+                if let Some(tip_action) = self.chain_tip_change.last_tip_change() {
+                    match tip_action {
+                        // Clear the mempool and cancel downloads if there has been a chain tip reset.
+                        TipAction::Reset { .. } => {
+                            storage.clear();
+                            tx_downloads.cancel_all();
+                        }
+                        TipAction::Grow { block } => {
+                            // Cancel downloads/verifications/storage of transactions
+                            // with the same mined IDs as recently mined transactions.
+                            let mined_ids = block.transaction_hashes.iter().cloned().collect();
+                            tx_downloads.cancel(&mined_ids);
+                            storage.remove_same_effects(&mined_ids);
+                            storage.clear_tip_rejections();
+                        }
+                    }
+                }
+
                 // Remove expired transactions from the mempool.
                 if let Some(tip_height) = self.latest_chain_tip.best_tip_height() {
                     let expired_transactions = remove_expired_transactions(storage, tip_height);