benchmark: denoise TextDecoder benchmark a bit, add utf-16le/be

Author: ChALkeR

benchmark/util/text-decoder-stream.js

@@ -2,21 +2,23 @@
 
 const common = require('../common.js');
 
+const MAX_N = 256 * 1024;
+const TOTAL_SIZE = 256 * 1024 * 1024;
+
 const bench = common.createBenchmark(main, {
   encoding: ['utf-8', 'utf-16le'],
   ignoreBOM: [0, 1],
   fatal: [0, 1],
   unicode: [0, 1],
   len: [256, 1024 * 16, 1024 * 128],
   chunks: [10],
-  n: [1e3],
   type: ['SharedArrayBuffer', 'ArrayBuffer', 'Buffer'],
 });
 
 const UNICODE_ALPHA = 'Blåbærsyltetøy';
 const ASCII_ALPHA = 'Blueberry jam';
 
-function main({ encoding, len, unicode, chunks, n, ignoreBOM, type, fatal }) {
+function main({ encoding, len, unicode, chunks, ignoreBOM, type, fatal }) {
   const decoder = new TextDecoder(encoding, { ignoreBOM, fatal });
   let buf;
 
@@ -41,6 +43,7 @@ function main({ encoding, len, unicode, chunks, n, ignoreBOM, type, fatal }) {
 
   const chunk = Math.ceil(len / chunks);
   const max = len - chunk;
+  const n = Math.min(MAX_N, Math.ceil(TOTAL_SIZE / len));
   bench.start();
   for (let i = 0; i < n; i++) {
     let pos = 0;

benchmark/util/text-decoder.js

@@ -3,7 +3,7 @@
 const common = require('../common.js');
 
 const bench = common.createBenchmark(main, {
-  encoding: ['utf-8', 'windows-1252', 'iso-8859-3'],
+  encoding: ['utf-8', 'utf-16le', 'utf-16be', 'windows-1252', 'iso-8859-3'],
   ignoreBOM: [0, 1],
   fatal: [0, 1],
   len: [256, 1024 * 16, 1024 * 128],
@@ -25,7 +25,7 @@ function main({ encoding, len, n, ignoreBOM, type, fatal }) {
       break;
     }
     case 'Buffer': {
-      buf = Buffer.allocUnsafe(len);
+      buf = Buffer.alloc(len);
       break;
     }
   }

lib/internal/encoding.js

@@ -484,7 +484,7 @@ class TextDecoder {
       this[kBOMSeen] = false;
     } else if (isSinglebyteEncoding(enc)) {
       this[kSingleByte] = createSinglebyteDecoder(enc, this[kFatal]);
-    } if (hasIntl) {
+    } else if (hasIntl) {
       let icuEncoding = this[kEncoding];
       if (icuEncoding === 'gbk') icuEncoding = 'gb18030'; // 10.1.1. GBK's decoder is gb18030's decoder
       const handle = icuGetConverter(icuEncoding, this[kFlags]);