util: add inspect suffix to BigInt64Array elements

This commit updates `util.inspect` to add an `n` suffix to BigInts that
appear in BigInt64Arrays. BigInts are formatted with an `n` suffix in
most cases, but this did not occur in BigInt64Arrays due to an apparent
oversight where the implementation of `inspect` for typed arrays assumed
that all typed array elements are numbers.

PR-URL: #21499
Reviewed-By: Michaël Zasso <targos@protonmail.com>
Reviewed-By: Gus Caplan <me@gus.host>
Reviewed-By: Ruben Bridgewater <ruben@bridgewater.de>
Reviewed-By: Tiancheng "Timothy" Gu <timothygu99@gmail.com>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Benjamin Gruenbaum <benjamingr@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Yuta Hiroto <hello@hiroppy.me>

Author: not-an-aardvark

lib/util.js

@@ -739,6 +739,10 @@ function formatNumber(fn, value) {
   return fn(`${value}`, 'number');
 }
 
+function formatBigInt(fn, value) {
+  return fn(`${value}n`, 'bigint');
+}
+
 function formatPrimitive(fn, value, ctx) {
   if (typeof value === 'string') {
     if (ctx.compact === false &&
@@ -779,7 +783,7 @@ function formatPrimitive(fn, value, ctx) {
     return formatNumber(fn, value);
   // eslint-disable-next-line valid-typeof
   if (typeof value === 'bigint')
-    return fn(`${value}n`, 'bigint');
+    return formatBigInt(fn, value);
   if (typeof value === 'boolean')
     return fn(`${value}`, 'boolean');
   if (typeof value === 'undefined')
@@ -915,8 +919,11 @@ function formatTypedArray(ctx, value, recurseTimes, keys) {
   const maxLength = Math.min(Math.max(0, ctx.maxArrayLength), value.length);
   const remaining = value.length - maxLength;
   const output = new Array(maxLength + (remaining > 0 ? 1 : 0));
+  const elementFormatter = value.length > 0 && typeof value[0] === 'number' ?
+    formatNumber :
+    formatBigInt;
   for (var i = 0; i < maxLength; ++i)
-    output[i] = formatNumber(ctx.stylize, value[i]);
+    output[i] = elementFormatter(ctx.stylize, value[i]);
   if (remaining > 0)
     output[i] = `... ${remaining} more item${remaining > 1 ? 's' : ''}`;
   if (ctx.showHidden) {

test/parallel/test-util-inspect-bigint.js

@@ -10,3 +10,5 @@ const { inspect } = require('util');
 assert.strictEqual(inspect(1n), '1n');
 assert.strictEqual(inspect(Object(-1n)), '[BigInt: -1n]');
 assert.strictEqual(inspect(Object(13n)), '[BigInt: 13n]');
+assert.strictEqual(inspect(new BigInt64Array([0n])), 'BigInt64Array [ 0n ]');
+assert.strictEqual(inspect(new BigUint64Array([0n])), 'BigUint64Array [ 0n ]');