improve: allow the monitored balances error/warn thresholds to be zero (

#2019)

Signed-off-by: bennett <[email protected]>

src/monitor/MonitorConfig.ts

@@ -1,6 +1,6 @@
 import winston from "winston";
 import { CommonConfig, ProcessEnv } from "../common";
-import { ethers, getNativeTokenAddressForChain } from "../utils";
+import { ethers, getNativeTokenAddressForChain, isDefined } from "../utils";
 
 // Set modes to true that you want to enable in the AcrossMonitor bot.
 export interface BotModes {
@@ -143,20 +143,20 @@ export class MonitorConfig extends CommonConfig {
     if (MONITORED_BALANCES) {
       this.monitoredBalances = JSON.parse(MONITORED_BALANCES).map(
         ({ errorThreshold, warnThreshold, account, token, chainId }) => {
-          if (!errorThreshold && !warnThreshold) {
+          if (!isDefined(errorThreshold) && !isDefined(warnThreshold)) {
             throw new Error("Must provide either an errorThreshold or a warnThreshold");
           }
 
           let parsedErrorThreshold: number | null = null;
-          if (errorThreshold) {
+          if (isDefined(errorThreshold)) {
             if (Number.isNaN(Number(errorThreshold))) {
               throw new Error(`errorThreshold value: ${errorThreshold} cannot be converted to a number`);
             }
             parsedErrorThreshold = Number(errorThreshold);
           }
 
           let parsedWarnThreshold: number | null = null;
-          if (warnThreshold) {
+          if (isDefined(warnThreshold)) {
             if (Number.isNaN(Number(errorThreshold))) {
               throw new Error(`warnThreshold value: ${warnThreshold} cannot be converted to a number`);
             }