refactor: Add interfaces::FoundBlock class to selectively return block data

FoundBlock class allows interfaces::Chain::findBlock to return more block
information without having lots of optional output parameters. FoundBlock class
is also used by other chain methods in upcoming commits.

There is mostly no change in behavior. Only exception is
CWallet::RescanFromTime now throwing NonFatalCheckError instead of
std::logic_error.

2 files changed, 10 insertions, 8 deletions

diff --git a/src/wallet/rpcwallet.cpp b/src/wallet/rpcwallet.cpp
index 5d34e592db..1e6d37c462 100644
--- a/src/wallet/rpcwallet.cpp
+++ b/src/wallet/rpcwallet.cpp
@@ -37,6 +37,8 @@
 #include <univalue.h>
 
 
+using interfaces::FoundBlock;
+
 static const std::string WALLET_ENDPOINT_BASE = "/wallet/";
 
 static inline bool GetAvoidReuseFlag(const CWallet* const pwallet, const UniValue& param) {
@@ -149,8 +151,7 @@ static void WalletTxToJSON(interfaces::Chain& chain, interfaces::Chain::Lock& lo
         entry.pushKV("blockheight", wtx.m_confirm.block_height);
         entry.pushKV("blockindex", wtx.m_confirm.nIndex);
         int64_t block_time;
-        bool found_block = chain.findBlock(wtx.m_confirm.hashBlock, nullptr /* block */, &block_time);
-        CHECK_NONFATAL(found_block);
+        CHECK_NONFATAL(chain.findBlock(wtx.m_confirm.hashBlock, FoundBlock().time(block_time)));
         entry.pushKV("blocktime", block_time);
     } else {
         entry.pushKV("trusted", wtx.IsTrusted(locked_chain));
@@ -1618,7 +1619,7 @@ static UniValue listsinceblock(const JSONRPCRequest& request)
     UniValue removed(UniValue::VARR);
     while (include_removed && altheight && *altheight > *height) {
         CBlock block;
-        if (!pwallet->chain().findBlock(blockId, &block) || block.IsNull()) {
+        if (!pwallet->chain().findBlock(blockId, FoundBlock().data(block)) || block.IsNull()) {
             throw JSONRPCError(RPC_INTERNAL_ERROR, "Can't read block from disk");
         }
         for (const CTransactionRef& tx : block.vtx) {
diff --git a/src/wallet/wallet.cpp b/src/wallet/wallet.cpp
index 98f308f927..c8641b03fb 100644
--- a/src/wallet/wallet.cpp
+++ b/src/wallet/wallet.cpp
@@ -22,6 +22,7 @@
 #include <script/script.h>
 #include <script/signingprovider.h>
 #include <util/bip32.h>
+#include <util/check.h>
 #include <util/error.h>
 #include <util/fees.h>
 #include <util/moneystr.h>
@@ -35,6 +36,8 @@
 
 #include <boost/algorithm/string/replace.hpp>
 
+using interfaces::FoundBlock;
+
 const std::map<uint64_t,std::string> WALLET_FLAG_CAVEATS{
     {WALLET_FLAG_AVOID_REUSE,
         "You need to rescan the blockchain in order to correctly mark used "
@@ -1601,9 +1604,7 @@ int64_t CWallet::RescanFromTime(int64_t startTime, const WalletRescanReserver& r
         ScanResult result = ScanForWalletTransactions(start_block, {} /* stop_block */, reserver, update);
         if (result.status == ScanResult::FAILURE) {
             int64_t time_max;
-            if (!chain().findBlock(result.last_failed_block, nullptr /* block */, nullptr /* time */, &time_max)) {
-                throw std::logic_error("ScanForWalletTransactions returned invalid block hash");
-            }
+            CHECK_NONFATAL(chain().findBlock(result.last_failed_block, FoundBlock().maxTime(time_max)));
             return time_max + TIMESTAMP_WINDOW + 1;
         }
     }
@@ -1671,7 +1672,7 @@ CWallet::ScanResult CWallet::ScanForWalletTransactions(const uint256& start_bloc
         }
 
         CBlock block;
-        if (chain().findBlock(block_hash, &block) && !block.IsNull()) {
+        if (chain().findBlock(block_hash, FoundBlock().data(block)) && !block.IsNull()) {
             auto locked_chain = chain().lock();
             LOCK(cs_wallet);
             if (!locked_chain->getBlockHeight(block_hash)) {
@@ -3622,7 +3623,7 @@ unsigned int CWallet::ComputeTimeSmart(const CWalletTx& wtx) const
     unsigned int nTimeSmart = wtx.nTimeReceived;
     if (!wtx.isUnconfirmed() && !wtx.isAbandoned()) {
         int64_t blocktime;
-        if (chain().findBlock(wtx.m_confirm.hashBlock, nullptr /* block */, &blocktime)) {
+        if (chain().findBlock(wtx.m_confirm.hashBlock, FoundBlock().time(blocktime))) {
             int64_t latestNow = wtx.nTimeReceived;
             int64_t latestEntry = 0;