From b283cfbc6eef86443b3cfe6bf3916ec691e82936 Mon Sep 17 00:00:00 2001
From: nvonpentz <12549658+nvonpentz@users.noreply.github.com>
Date: Mon, 27 Feb 2023 15:37:54 -0500
Subject: [PATCH 1/2] Fix asset discovery for cUSDT

When checking if a BalanceScanner result is > 0 for asset discovery,
convert the balance to an integer instead of doing a string comparison.
---
 .../asset_discovery_manager_unittest.cc       | 19 +++++++++++++++++++
 .../browser/asset_discovery_manager.cc        | 13 +++++++------
 2 files changed, 26 insertions(+), 6 deletions(-)

diff --git a/browser/brave_wallet/asset_discovery_manager_unittest.cc b/browser/brave_wallet/asset_discovery_manager_unittest.cc
index 4ffd308375e2..d7d3a11f565c 100644
--- a/browser/brave_wallet/asset_discovery_manager_unittest.cc
+++ b/browser/brave_wallet/asset_discovery_manager_unittest.cc
@@ -1125,6 +1125,25 @@ TEST_F(AssetDiscoveryManagerUnitTest, DiscoverEthAssets) {
   TestDiscoverEthAssets({"0xB4B2802129071b2B9eBb8cBB01EA1E4D14B34961"}, false,
                         {});
 
+  // One account returns the cUSDT token response for no balance detected
+  // (successful), yields no discovered contract addresses
+  const char cusdt_balance_not_detected_response[] = R"({
+        "jsonrpc":"2.0",
+        "id":1,
+        "result":"0x000000000000000000000000000000000000000000000000000000000000002000000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000020000000000000000000000000000000000000000000000000000000000000000100000000000000000000000000000000000000000000000000000000000000400000000000000000000000000000000000000000000000000000000000000060000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000"
+    })";
+
+  requests = {
+      {GetNetwork(mojom::kMainnetChainId, mojom::CoinType::ETH),
+       {
+           {"0xB4B2802129071b2B9eBb8cBB01EA1E4D14B34961",
+            cusdt_balance_not_detected_response},
+       }},
+  };
+  SetInterceptorForDiscoverEthAssets(requests);
+  TestDiscoverEthAssets({"0xB4B2802129071b2B9eBb8cBB01EA1E4D14B34961"}, false,
+                        {});
+
   // One account, with a balance, yields discovered contract address
   requests = {
       {GetNetwork(mojom::kMainnetChainId, mojom::CoinType::ETH),
diff --git a/components/brave_wallet/browser/asset_discovery_manager.cc b/components/brave_wallet/browser/asset_discovery_manager.cc
index c7d7cab49ae8..dc0b694d52e5 100644
--- a/components/brave_wallet/browser/asset_discovery_manager.cc
+++ b/components/brave_wallet/browser/asset_discovery_manager.cc
@@ -279,12 +279,13 @@ void AssetDiscoveryManager::OnGetERC20TokenBalances(
 
   // Populate the map using the balance_results
   for (size_t i = 0; i < balance_results.size(); i++) {
-    if (balance_results[i]->balance.has_value() &&
-        balance_results[i]->balance !=
-            "0x000000000000000000000000000000000000000000000000000000000000000"
-            "0") {
-      chain_id_to_contract_addresses_with_balance[chain_id].push_back(
-          contract_addresses[i]);
+    if (balance_results[i]->balance.has_value()) {
+      uint256_t balance_uint;
+      HexValueToUint256(balance_results[i]->balance.value(), &balance_uint);
+      if (balance_uint > 0) {
+        chain_id_to_contract_addresses_with_balance[chain_id].push_back(
+            contract_addresses[i]);
+      }
     }
   }
 

From 5044d49c624f037ac7644adc94e98203f09b91e4 Mon Sep 17 00:00:00 2001
From: nvonpentz <12549658+nvonpentz@users.noreply.github.com>
Date: Mon, 27 Feb 2023 15:54:40 -0500
Subject: [PATCH 2/2] Handle case when HexValueToUint256 fails

---
 components/brave_wallet/browser/asset_discovery_manager.cc | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/components/brave_wallet/browser/asset_discovery_manager.cc b/components/brave_wallet/browser/asset_discovery_manager.cc
index dc0b694d52e5..4ca0a1cae8dc 100644
--- a/components/brave_wallet/browser/asset_discovery_manager.cc
+++ b/components/brave_wallet/browser/asset_discovery_manager.cc
@@ -281,8 +281,9 @@ void AssetDiscoveryManager::OnGetERC20TokenBalances(
   for (size_t i = 0; i < balance_results.size(); i++) {
     if (balance_results[i]->balance.has_value()) {
       uint256_t balance_uint;
-      HexValueToUint256(balance_results[i]->balance.value(), &balance_uint);
-      if (balance_uint > 0) {
+      bool success =
+          HexValueToUint256(balance_results[i]->balance.value(), &balance_uint);
+      if (success && balance_uint > 0) {
         chain_id_to_contract_addresses_with_balance[chain_id].push_back(
             contract_addresses[i]);
       }