Move logic from LookupUTXOStatsWithIndex to CoinStatsIndex::LookUpStats

The indexing codepath logic in node/coinstats.cpp is simple enough to be
moved into CoinStatsIndex::LookUpStats, avoiding an additional layer of
function calls. Callers are modified accordingly.

Also, add 2 missed BOOST_CHECKs to the coinstatsindex_initial_sync unit
test.

2 files changed, 21 insertions, 18 deletions

diff --git a/src/index/coinstatsindex.cpp b/src/index/coinstatsindex.cpp
index 69078708f9..c4bc47e538 100644
--- a/src/index/coinstatsindex.cpp
+++ b/src/index/coinstatsindex.cpp
@@ -316,28 +316,31 @@ static bool LookUpOne(const CDBWrapper& db, const CBlockIndex* block_index, DBVa
     return db.Read(DBHashKey(block_index->GetBlockHash()), result);
 }
 
-bool CoinStatsIndex::LookUpStats(const CBlockIndex* block_index, CCoinsStats& coins_stats) const
+std::optional<CCoinsStats> CoinStatsIndex::LookUpStats(const CBlockIndex* block_index) const
 {
+    CCoinsStats stats{Assert(block_index)->nHeight, block_index->GetBlockHash()};
+    stats.index_used = true;
+
     DBVal entry;
     if (!LookUpOne(*m_db, block_index, entry)) {
-        return false;
+        return std::nullopt;
     }
 
-    coins_stats.hashSerialized = entry.muhash;
-    coins_stats.nTransactionOutputs = entry.transaction_output_count;
-    coins_stats.nBogoSize = entry.bogo_size;
-    coins_stats.total_amount = entry.total_amount;
-    coins_stats.total_subsidy = entry.total_subsidy;
-    coins_stats.total_unspendable_amount = entry.total_unspendable_amount;
-    coins_stats.total_prevout_spent_amount = entry.total_prevout_spent_amount;
-    coins_stats.total_new_outputs_ex_coinbase_amount = entry.total_new_outputs_ex_coinbase_amount;
-    coins_stats.total_coinbase_amount = entry.total_coinbase_amount;
-    coins_stats.total_unspendables_genesis_block = entry.total_unspendables_genesis_block;
-    coins_stats.total_unspendables_bip30 = entry.total_unspendables_bip30;
-    coins_stats.total_unspendables_scripts = entry.total_unspendables_scripts;
-    coins_stats.total_unspendables_unclaimed_rewards = entry.total_unspendables_unclaimed_rewards;
-
-    return true;
+    stats.hashSerialized = entry.muhash;
+    stats.nTransactionOutputs = entry.transaction_output_count;
+    stats.nBogoSize = entry.bogo_size;
+    stats.total_amount = entry.total_amount;
+    stats.total_subsidy = entry.total_subsidy;
+    stats.total_unspendable_amount = entry.total_unspendable_amount;
+    stats.total_prevout_spent_amount = entry.total_prevout_spent_amount;
+    stats.total_new_outputs_ex_coinbase_amount = entry.total_new_outputs_ex_coinbase_amount;
+    stats.total_coinbase_amount = entry.total_coinbase_amount;
+    stats.total_unspendables_genesis_block = entry.total_unspendables_genesis_block;
+    stats.total_unspendables_bip30 = entry.total_unspendables_bip30;
+    stats.total_unspendables_scripts = entry.total_unspendables_scripts;
+    stats.total_unspendables_unclaimed_rewards = entry.total_unspendables_unclaimed_rewards;
+
+    return stats;
 }
 
 bool CoinStatsIndex::Init()
diff --git a/src/index/coinstatsindex.h b/src/index/coinstatsindex.h
index 6f53bb74fb..a6c935c25e 100644
--- a/src/index/coinstatsindex.h
+++ b/src/index/coinstatsindex.h
@@ -56,7 +56,7 @@ public:
     explicit CoinStatsIndex(size_t n_cache_size, bool f_memory = false, bool f_wipe = false);
 
     // Look up stats for a specific block using CBlockIndex
-    bool LookUpStats(const CBlockIndex* block_index, node::CCoinsStats& coins_stats) const;
+    std::optional<node::CCoinsStats> LookUpStats(const CBlockIndex* block_index) const;
 };
 
 /// The global UTXO set hash object.