Leave configurable dust when swapping tokens

ts/config.ts

@@ -104,4 +104,5 @@ export interface IConfig {
   tokenListStrategy: "explorer" | "chain";
   lookbackRange: number;
   confirmDrip: boolean;
+  leaveDust: BigNumber;
 }

ts/drip/dripItAll.ts

@@ -25,7 +25,7 @@ export async function dripItAll(
     tokensToSwap.map((token) => ({
       symbol: token.symbol,
       address: token.address,
-      balance: formatUnits(token.balance, token.decimals),
+      balance: formatUnits(token.adjustedBalance, token.decimals),
       buyAmount: formatUnits(token.buyAmount, WETH_DECIMALS),
       needsApproval: token.needsApproval,
     }))

ts/drip/getTokensToSwap.ts

@@ -12,7 +12,7 @@ import { getAllowances } from "./getAllowances";
 
 export interface GetTokensToSwapResult {
   buyAmount: BigNumber;
-  balance: BigNumber;
+  adjustedBalance: BigNumber;
   allowance: BigNumber;
   needsApproval: boolean;
   address: string;
@@ -45,7 +45,7 @@ export async function getTokensToSwap(
   // minValue filter again with _real_ balance
   const unfilteredWithBalanceAndAllowance = unfiltered.map((token, idx) => ({
     ...token,
-    balance: balances[idx],
+    adjustedBalance: balances[idx].sub(config.leaveDust),
     allowance: allowances[idx],
     needsApproval: allowances[idx].lt(balances[idx]),
   }));
@@ -56,7 +56,7 @@ export async function getTokensToSwap(
     unfilteredWithBalanceAndAllowance.map((token) =>
       orderBookApi.getQuote({
         sellToken: token.address,
-        sellAmountBeforeFee: token.balance.toString(),
+        sellAmountBeforeFee: token.adjustedBalance.toString(),
         kind: OrderQuoteSideKindSell.SELL,
         buyToken: config.wrappedNativeToken,
         from: config.gpv2Settlement,

ts/drip/postOrders.ts

@@ -22,7 +22,7 @@ export async function postOrders(
       orderBookApi.sendOrder({
         sellToken: token.address,
         buyToken: config.wrappedNativeToken,
-        sellAmount: token.balance.toString(),
+        sellAmount: token.adjustedBalance.toString(),
         buyAmount: token.buyAmount.toString(),
         validTo: nextValidTo,
         appData: appDataContent,

ts/drip/swapTokens.ts

@@ -50,7 +50,7 @@ export const swapTokens = async (
 
   const toDrip = toActuallySwap.map((token) => ({
     token: token.address,
-    sellAmount: token.balance,
+    sellAmount: token.adjustedBalance,
     buyAmount: token.buyAmount,
   }));
 

ts/utils/readConfig.ts

@@ -72,6 +72,14 @@ export async function readConfig(): Promise<
         "-c, --confirm-drip",
         "Ask for confirmation before dripping"
       ).default(false)
+    )
+    .addOption(
+      new Option(
+        "--leave-dust <wei>",
+        "Amount of each token (in wei) to leave in the contract after swapping"
+      )
+        .default(BigNumber.from(10))
+        .argParser((x) => BigNumber.from(x))
     );
 
   program.parse();
@@ -88,6 +96,7 @@ export async function readConfig(): Promise<
     lookbackRange,
     tokenListStrategy,
     confirmDrip,
+    leaveDust,
   } = options;
   const network = selectedNetwork || "mainnet";
 
@@ -147,6 +156,7 @@ export async function readConfig(): Promise<
       lookbackRange,
       targetSafe,
       confirmDrip,
+      leaveDust,
     },
     provider,
   ];