Return a status enum from ScanForWalletTransactions

Return the failed block as an out var.

This clarifies the outcome as the prior return value could
be null due to user abort or failure.

1 files changed, 10 insertions, 8 deletions

diff --git a/src/wallet/rpcwallet.cpp b/src/wallet/rpcwallet.cpp
index 1514c978b8..c3f12f373d 100644
--- a/src/wallet/rpcwallet.cpp
+++ b/src/wallet/rpcwallet.cpp
@@ -3332,16 +3332,18 @@ UniValue rescanblockchain(const JSONRPCRequest& request)
         }
     }
 
-    const CBlockIndex* stopBlock = pwallet->ScanForWalletTransactions(pindexStart, pindexStop, reserver, true);
-    if (!stopBlock) {
-        if (pwallet->IsAbortingRescan()) {
-            throw JSONRPCError(RPC_MISC_ERROR, "Rescan aborted.");
-        }
-        // if we got a nullptr returned, ScanForWalletTransactions did rescan up to the requested stopindex
+    const CBlockIndex* stopBlock;
+    CWallet::ScanResult result =
+        pwallet->ScanForWalletTransactions(pindexStart, pindexStop, reserver, stopBlock, true);
+    switch (result) {
+    case CWallet::ScanResult::SUCCESS:
         stopBlock = pindexStop ? pindexStop : pChainTip;
-    }
-    else {
+        break;
+    case CWallet::ScanResult::FAILURE:
         throw JSONRPCError(RPC_MISC_ERROR, "Rescan failed. Potentially corrupted data files.");
+    case CWallet::ScanResult::USER_ABORT:
+        throw JSONRPCError(RPC_MISC_ERROR, "Rescan aborted.");
+        // no default case, so the compiler can warn about missing cases
     }
     UniValue response(UniValue::VOBJ);
     response.pushKV("start_height", pindexStart->nHeight);