[mempool] Revert unbroadcast set to tracking just txid

When I originally implemented the unbroadcast set in 18038, it just tracked
txids. After 18038 was merged, I offered a patch to 18044 to make the
unbroadcast changes compatible with wtxid relay. In this patch, I updated
`unbroadcast_txids` to a map of txid -> wtxid. Post merge review comments shed
light on the fact that this update was unnecessary, and distracting. So, this
commit updates the unbroadcast ids back to a set.

1 files changed, 10 insertions, 10 deletions

diff --git a/src/txmempool.h b/src/txmempool.h
index f773cd4825..62a836ce67 100644
--- a/src/txmempool.h
+++ b/src/txmempool.h
@@ -574,10 +574,9 @@ private:
     std::vector<indexed_transaction_set::const_iterator> GetSortedDepthAndScore() const EXCLUSIVE_LOCKS_REQUIRED(cs);
 
     /**
-     * track locally submitted transactions to periodically retry initial broadcast
-     * map of txid -> wtxid
+     * Track locally submitted transactions to periodically retry initial broadcast.
      */
-    std::map<uint256, uint256> m_unbroadcast_txids GUARDED_BY(cs);
+    std::set<uint256> m_unbroadcast_txids GUARDED_BY(cs);
 
 public:
     indirectmap<COutPoint, const CTransaction*> mapNextTx GUARDED_BY(cs);
@@ -739,19 +738,20 @@ public:
     size_t DynamicMemoryUsage() const;
 
     /** Adds a transaction to the unbroadcast set */
-    void AddUnbroadcastTx(const uint256& txid, const uint256& wtxid) {
+    void AddUnbroadcastTx(const uint256& txid)
+    {
         LOCK(cs);
-        // Sanity Check: the transaction should also be in the mempool
-        if (exists(txid)) {
-            m_unbroadcast_txids[txid] = wtxid;
-        }
-    }
+        // Sanity check the transaction is in the mempool & insert into
+        // unbroadcast set.
+        if (exists(txid)) m_unbroadcast_txids.insert(txid);
+    };
 
     /** Removes a transaction from the unbroadcast set */
     void RemoveUnbroadcastTx(const uint256& txid, const bool unchecked = false);
 
     /** Returns transactions in unbroadcast set */
-    std::map<uint256, uint256> GetUnbroadcastTxs() const {
+    std::set<uint256> GetUnbroadcastTxs() const
+    {
         LOCK(cs);
         return m_unbroadcast_txids;
     }