Merge pull request NomicFoundation#1989 from nomiclabs/hardhat-node-w…

…arning

Print a warning in the node task about the accounts being shared

.changeset/thick-paws-pretend.md

@@ -0,0 +1,5 @@
+---
+"hardhat": patch
+---
+
+Print a warning in the node task if the default accounts are used.

docs/advanced/hardhat-runtime-environment.md

@@ -66,6 +66,5 @@ extendEnvironment((hre) => {
 
   // hre.network.provider is an EIP1193-compatible provider.
   hre.web3 = new Web3(hre.network.provider);
-
 });
 ```

packages/hardhat-core/src/builtin-tasks/node.ts

@@ -20,6 +20,7 @@ import {
   JsonRpcServer,
 } from "../types";
 
+import { HARDHAT_NETWORK_MNEMONIC } from "../internal/core/config/default-config";
 import {
   TASK_NODE,
   TASK_NODE_CREATE_SERVER,
@@ -31,31 +32,62 @@ import { watchCompilerOutput } from "./utils/watch";
 
 const log = debug("hardhat:core:tasks:node");
 
+function printDefaultConfigWarning() {
+  console.log(
+    chalk.bold(
+      "WARNING: These accounts, and their private keys, are publicly known."
+    )
+  );
+  console.log(
+    chalk.bold(
+      "Any funds sent to them on Mainnet or any other live network WILL BE LOST."
+    )
+  );
+}
+
 function logHardhatNetworkAccounts(networkConfig: HardhatNetworkConfig) {
-  if (networkConfig.accounts === undefined) {
-    return;
-  }
+  const isDefaultConfig =
+    !Array.isArray(networkConfig.accounts) &&
+    networkConfig.accounts.mnemonic === HARDHAT_NETWORK_MNEMONIC;
 
   const { BN, bufferToHex, privateToAddress, toBuffer } =
     require("ethereumjs-util") as typeof EthereumjsUtilT;
 
   console.log("Accounts");
   console.log("========");
 
+  if (isDefaultConfig) {
+    console.log();
+    printDefaultConfigWarning();
+    console.log();
+  }
+
   const accounts = normalizeHardhatNetworkAccountsConfig(
     networkConfig.accounts
   );
 
   for (const [index, account] of accounts.entries()) {
     const address = bufferToHex(privateToAddress(toBuffer(account.privateKey)));
-    const privateKey = bufferToHex(toBuffer(account.privateKey));
+
     const balance = new BN(account.balance)
       .div(new BN(10).pow(new BN(18)))
       .toString(10);
 
-    console.log(`Account #${index}: ${address} (${balance} ETH)
-Private Key: ${privateKey}
-`);
+    let entry = `Account #${index}: ${address} (${balance} ETH)`;
+
+    if (isDefaultConfig) {
+      const privateKey = bufferToHex(toBuffer(account.privateKey));
+      entry += `
+Private Key: ${privateKey}`;
+    }
+
+    console.log(entry);
+    console.log();
+  }
+
+  if (isDefaultConfig) {
+    printDefaultConfigWarning();
+    console.log();
   }
 }
 

packages/hardhat-core/src/internal/core/config/default-config.ts

@@ -7,7 +7,7 @@ export const DEFAULT_SOLC_VERSION = "0.7.3";
 export const HARDHAT_NETWORK_DEFAULT_GAS_PRICE = "auto";
 export const HARDHAT_NETWORK_DEFAULT_MAX_PRIORITY_FEE_PER_GAS = 1e9;
 export const HARDHAT_NETWORK_DEFAULT_INITIAL_BASE_FEE_PER_GAS = 1e9;
-const HARDHAT_NETWORK_MNEMONIC =
+export const HARDHAT_NETWORK_MNEMONIC =
   "test test test test test test test test test test test junk";
 export const DEFAULT_HARDHAT_NETWORK_BALANCE = "10000000000000000000000";