Fix error printing for unknown errors

Author: schaable

v-next/hardhat/src/internal/cli/error-handler.ts

@@ -1,3 +1,5 @@
+import util from "node:util";
+
 import {
   HardhatError,
   HardhatPluginError,
@@ -84,7 +86,7 @@ export function printErrorMessages(
     /* eslint-disable-next-line @typescript-eslint/restrict-template-expressions
     -- As we don't know the type of error we are printing, we can't know if it
     has a `stack` property or not, so we print it as a string. */
-    print(error instanceof Error ? `${error.stack}` : `${error}`);
+    print(error instanceof Error ? `${error.stack}` : `${util.inspect(error)}`);
     if (postErrorStackTraceMessage !== undefined) {
       print("");
       print(postErrorStackTraceMessage);

v-next/hardhat/test/internal/cli/error-handler.ts

@@ -1,5 +1,6 @@
 import assert from "node:assert/strict";
 import { beforeEach, describe, it } from "node:test";
+import util from "node:util";
 
 import {
   HardhatError,
@@ -278,7 +279,7 @@ describe("error-handler", () => {
         assert.equal(lines.length, 5);
         assert.equal(lines[0], chalk.red.bold(`An unexpected error occurred:`));
         assert.equal(lines[1], "");
-        assert.equal(lines[2], `${error}`);
+        assert.equal(lines[2], `${util.inspect(error)}`);
         assert.equal(lines[3], "");
         assert.equal(
           lines[4],