evm: fix keep balance when resetting an account (#353)

* keep balance when override account

* Update CHANGELOG.md

Co-authored-by: Federico Kunze Küllmer <31522760+fedekunze@users.noreply.github.com>

CHANGELOG.md

@@ -46,6 +46,7 @@ Ref: https://keepachangelog.com/en/1.0.0/
 * (evm) [tharsis#68](https://github.com/tharsis/ethermint/issues/68) Replace block hash storage map to use staking `HistoricalInfo`.
 * (evm) [tharsis#276](https://github.com/tharsis/ethermint/pull/276) Vm errors don't result in cosmos tx failure, just
   different tx state and events.
+* (evm) [tharsis#342](https://github.com/tharsis/ethermint/issues/342) Don't clear balance when resetting the account.
 
 ### API Breaking
 

x/evm/keeper/keeper.go

@@ -316,17 +316,9 @@ func (k Keeper) ClearBalance(addr sdk.AccAddress) (prevBalance sdk.Coin, err err
 	return prevBalance, nil
 }
 
-// ResetAccount removes the code, storage state and evm denom balance coins stored
+// ResetAccount removes the code, storage state, but keep all the native tokens stored
 // with the given address.
 func (k Keeper) ResetAccount(addr common.Address) {
 	k.DeleteCode(addr)
 	k.DeleteAccountStorage(addr)
-	_, err := k.ClearBalance(addr.Bytes())
-	if err != nil {
-		k.Logger(k.ctx).Error(
-			"failed to clear balance during account reset",
-			"ethereum-address", addr.Hex(),
-			"error", err,
-		)
-	}
 }

x/evm/keeper/statedb_test.go

@@ -27,14 +27,14 @@ func (suite *KeeperTestSuite) TestCreateAccount() {
 		callback func(common.Address)
 	}{
 		{
-			"reset account",
+			"reset account (keep balance)",
 			suite.address,
 			func(addr common.Address) {
 				suite.app.EvmKeeper.AddBalance(addr, big.NewInt(100))
 				suite.Require().NotZero(suite.app.EvmKeeper.GetBalance(addr).Int64())
 			},
 			func(addr common.Address) {
-				suite.Require().Zero(suite.app.EvmKeeper.GetBalance(addr).Int64())
+				suite.Require().Equal(suite.app.EvmKeeper.GetBalance(addr).Int64(), int64(100))
 			},
 		},
 		{