benchmark: reduce string concatenations

PR-URL: https://github.com/nodejs/node/pull/12455 Reviewed-By: Benjamin Gruenbaum <benjamingr@gmail.com> Reviewed-By: James M Snell <jasnell@gmail.com>
8 years ago · 22aa3d4899
61 changed files with 168 additions and 162 deletions
--- a/benchmark/_benchmark_progress.js
+++ b/benchmark/_benchmark_progress.js
@ -3,12 +3,13 @@
 const readline = require('readline');

 function pad(input, minLength, fill) {
-  var result = input + '';
-  return fill.repeat(Math.max(0, minLength - result.length)) + result;
+  var result = String(input);
+  var padding = fill.repeat(Math.max(0, minLength - result.length));
+  return `${padding}${result}`;
 }

 function fraction(numerator, denominator) {
-  const fdenominator = denominator + '';
+  const fdenominator = String(denominator);
  const fnumerator = pad(numerator, fdenominator.length, ' ');
  return `${fnumerator}/${fdenominator}`;
 }
@ -100,11 +101,12 @@ class BenchmarkProgress {
    const percent = pad(Math.floor(completedRate * 100), 3, ' ');

    const caption = finished ? 'Done\n' : this.currentFile;
-    return `[${getTime(diff)}|% ${percent}` +
-          `| ${fraction(completedFiles, scheduledFiles)} files ` +
-          `| ${fraction(completedRunsForFile, runsPerFile)} runs ` +
-          `| ${fraction(completedConfig, scheduledConfig)} configs]` +
-          `: ${caption} `;
+    return `[${getTime(diff)}|% ${
+               percent}| ${
+               fraction(completedFiles, scheduledFiles)} files | ${
+               fraction(completedRunsForFile, runsPerFile)} runs | ${
+               fraction(completedConfig, scheduledConfig)} configs]: ${
+               caption} `;
  }

  updateProgress(finished) {
--- a/benchmark/_http-benchmarkers.js
+++ b/benchmark/_http-benchmarkers.js
@ -4,6 +4,9 @@ const child_process = require('child_process');
 const path = require('path');
 const fs = require('fs');

+const requirementsURL =
+  'https://github.com/nodejs/node/blob/master/doc/guides/writing-and-running-benchmarks.md##http-benchmark-requirements';
+
 // The port used by servers and wrk
 exports.PORT = process.env.PORT || 12346;

@ -133,20 +136,19 @@ exports.run = function(options, callback) {
    benchmarker: exports.default_http_benchmarker
  }, options);
  if (!options.benchmarker) {
-    callback(new Error('Could not locate required http benchmarker. See ' +
-                       'https://github.com/nodejs/node/blob/master/doc/guides/writing-and-running-benchmarks.md##http-benchmark-requirements ' +
-                       'for further instructions.'));
+    callback(new Error(`Could not locate required http benchmarker. See ${
+                        requirementsURL} for further instructions.`));
    return;
  }
  const benchmarker = benchmarkers[options.benchmarker];
  if (!benchmarker) {
-    callback(new Error(`Requested benchmarker '${options.benchmarker}' is ` +
-                       'not supported'));
+    callback(new Error(`Requested benchmarker '${
+                        options.benchmarker}' is  not supported`));
    return;
  }
  if (!benchmarker.present) {
-    callback(new Error(`Requested benchmarker '${options.benchmarker}' is ` +
-                       'not installed'));
+    callback(new Error(`Requested benchmarker '${
+                        options.benchmarker}' is  not installed`));
    return;
  }

@ -172,8 +174,8 @@ exports.run = function(options, callback) {

    const result = benchmarker.processResults(stdout);
    if (result === undefined) {
-      callback(new Error(`${options.benchmarker} produced strange output: ` +
-                         stdout, code));
+      callback(new Error(
+        `${options.benchmarker} produced strange output: ${stdout}`, code));
      return;
    }

--- a/benchmark/assert/deepequal-typedarrays.js
+++ b/benchmark/assert/deepequal-typedarrays.js
@ -2,8 +2,17 @@
 const common = require('../common.js');
 const assert = require('assert');
 const bench = common.createBenchmark(main, {
-  type: ('Int8Array Uint8Array Int16Array Uint16Array Int32Array Uint32Array ' +
-    'Float32Array Float64Array Uint8ClampedArray').split(' '),
+  type: [
+    'Int8Array',
+    'Uint8Array',
+    'Int16Array',
+    'Uint16Array',
+    'Int32Array',
+    'Uint32Array',
+    'Float32Array',
+    'Float64Array',
+    'Uint8ClampedArray',
+  ],
  n: [1],
  method: ['strict', 'nonstrict'],
  len: [1e6]
--- a/benchmark/buffers/buffer-base64-decode-wrapped.js
+++ b/benchmark/buffers/buffer-base64-decode-wrapped.js
@ -12,7 +12,7 @@ function main(conf) {
  const linesCount = 8 << 16;
  const bytesCount = charsPerLine * linesCount / 4 * 3;

-  const line = 'abcd'.repeat(charsPerLine / 4) + '\n';
+  const line = `${'abcd'.repeat(charsPerLine / 4)}\n`;
  const data = line.repeat(linesCount);
  // eslint-disable-next-line no-unescaped-regexp-dot
  data.match(/./);  // Flatten the string
--- a/benchmark/buffers/buffer-bytelength.js
+++ b/benchmark/buffers/buffer-bytelength.js
@ -28,7 +28,7 @@ function main(conf) {
  } else {
    for (var string of chars) {
      // Strings must be built differently, depending on encoding
-      var data = buildString(string, len);
+      var data = string.repeat(len);
      if (encoding === 'utf8') {
        strings.push(data);
      } else if (encoding === 'base64') {
@ -54,9 +54,3 @@ function main(conf) {
  }
  bench.end(n);
 }
-
-function buildString(str, times) {
-  if (times === 1) return str;
-
-  return str + buildString(str, times - 1);
-}
--- a/benchmark/buffers/buffer-read.js
+++ b/benchmark/buffers/buffer-read.js
@ -30,14 +30,14 @@ function main(conf) {
  var len = +conf.millions * 1e6;
  var clazz = conf.buf === 'fast' ? Buffer : require('buffer').SlowBuffer;
  var buff = new clazz(8);
-  var fn = 'read' + conf.type;
+  var fn = `read${conf.type}`;

  buff.writeDoubleLE(0, 0, noAssert);
-  var testFunction = new Function('buff', [
-    'for (var i = 0; i !== ' + len + '; i++) {',
-    '  buff.' + fn + '(0, ' + JSON.stringify(noAssert) + ');',
-    '}'
-  ].join('\n'));
+  var testFunction = new Function('buff', `
+    for (var i = 0; i !== ${len}; i++) {
+      buff.${fn}(0, ${JSON.stringify(noAssert)});
+    }
+  `);
  bench.start();
  testFunction(buff);
  bench.end(len / 1e6);
--- a/benchmark/buffers/buffer-swap.js
+++ b/benchmark/buffers/buffer-swap.js
@ -64,11 +64,11 @@ function createBuffer(len, aligned) {
 }

 function genMethod(method) {
-  const fnString =
-      'return function ' + method + '(n, buf) {' +
-      '  for (var i = 0; i <= n; i++)' +
-      '    buf.' + method + '();' +
-      '}';
+  const fnString = `
+      return function ${method}(n, buf) {
+        for (var i = 0; i <= n; i++)
+          buf.${method}();
+      }`;
  return (new Function(fnString))();
 }

--- a/benchmark/buffers/buffer-write.js
+++ b/benchmark/buffers/buffer-write.js
@ -50,7 +50,7 @@ function main(conf) {
  var len = +conf.millions * 1e6;
  var clazz = conf.buf === 'fast' ? Buffer : require('buffer').SlowBuffer;
  var buff = new clazz(8);
-  var fn = 'write' + conf.type;
+  var fn = `write${conf.type}`;

  if (fn.match(/Int/))
    benchInt(buff, fn, len, noAssert);
@ -60,22 +60,22 @@ function main(conf) {

 function benchInt(buff, fn, len, noAssert) {
  var m = mod[fn];
-  var testFunction = new Function('buff', [
-    'for (var i = 0; i !== ' + len + '; i++) {',
-    '  buff.' + fn + '(i & ' + m + ', 0, ' + JSON.stringify(noAssert) + ');',
-    '}'
-  ].join('\n'));
+  var testFunction = new Function('buff', `
+    for (var i = 0; i !== ${len}; i++) {
+      buff.${fn}(i & ${m}, 0, ${JSON.stringify(noAssert)});
+    }
+  `);
  bench.start();
  testFunction(buff);
  bench.end(len / 1e6);
 }

 function benchFloat(buff, fn, len, noAssert) {
-  var testFunction = new Function('buff', [
-    'for (var i = 0; i !== ' + len + '; i++) {',
-    '  buff.' + fn + '(i, 0, ' + JSON.stringify(noAssert) + ');',
-    '}'
-  ].join('\n'));
+  var testFunction = new Function('buff', `
+    for (var i = 0; i !== ${len}; i++) {
+      buff.${fn}(i, 0, ${JSON.stringify(noAssert)});
+    }
+  `);
  bench.start();
  testFunction(buff);
  bench.end(len / 1e6);
--- a/benchmark/buffers/dataview-set.js
+++ b/benchmark/buffers/dataview-set.js
@ -44,7 +44,7 @@ function main(conf) {
  var ab = new ArrayBuffer(8);
  var dv = new DataView(ab, 0, 8);
  var le = /LE$/.test(conf.type);
-  var fn = 'set' + conf.type.replace(/[LB]E$/, '');
+  var fn = `set${conf.type.replace(/[LB]E$/, '')}`;

  if (/int/i.test(fn))
    benchInt(dv, fn, len, le);
--- a/benchmark/common.js
+++ b/benchmark/common.js
@ -44,7 +44,7 @@ Benchmark.prototype._parseArgs = function(argv, configs) {
  for (const arg of argv) {
    const match = arg.match(/^(.+?)=([\s\S]*)$/);
    if (!match) {
-      console.error('bad argument: ' + arg);
+      console.error(`bad argument: ${arg}`);
      process.exit(1);
    }
    const config = match[1];
@ -206,7 +206,7 @@ function formatResult(data) {
  // Construct configuration string, " A=a, B=b, ..."
  let conf = '';
  for (const key of Object.keys(data.conf)) {
-    conf += ' ' + key + '=' + JSON.stringify(data.conf[key]);
+    conf += ` ${key}=${JSON.stringify(data.conf[key])}`;
  }

  var rate = data.rate.toString().split('.');
--- a/benchmark/compare.js
+++ b/benchmark/compare.js
@ -79,14 +79,14 @@ if (showProgress) {
      // Construct configuration string, " A=a, B=b, ..."
      let conf = '';
      for (const key of Object.keys(data.conf)) {
-        conf += ' ' + key + '=' + JSON.stringify(data.conf[key]);
+        conf += ` ${key}=${JSON.stringify(data.conf[key])}`;
      }
      conf = conf.slice(1);
      // Escape quotes (") for correct csv formatting
      conf = conf.replace(/"/g, '""');

-      console.log(`"${job.binary}", "${job.filename}", "${conf}", ` +
-                  `${data.rate}, ${data.time}`);
+      console.log(`"${job.binary}", "${job.filename}", "${conf}", ${
+                   data.rate}, ${data.time}`);
      if (showProgress) {
        // One item in the subqueue has been completed.
        progress.completeConfig(data);
--- a/benchmark/crypto/cipher-stream.js
+++ b/benchmark/crypto/cipher-stream.js
@ -51,7 +51,7 @@ function main(conf) {
      message = Buffer.alloc(conf.len, 'b');
      break;
    default:
-      throw new Error('unknown message type: ' + conf.type);
+      throw new Error(`unknown message type: ${conf.type}`);
  }

  var fn = api === 'stream' ? streamWrite : legacyWrite;
--- a/benchmark/crypto/hash-stream-creation.js
+++ b/benchmark/crypto/hash-stream-creation.js
@ -36,7 +36,7 @@ function main(conf) {
      message = Buffer.alloc(conf.len, 'b');
      break;
    default:
-      throw new Error('unknown message type: ' + conf.type);
+      throw new Error(`unknown message type: ${conf.type}`);
  }

  var fn = api === 'stream' ? streamWrite : legacyWrite;
--- a/benchmark/crypto/hash-stream-throughput.js
+++ b/benchmark/crypto/hash-stream-throughput.js
@ -35,7 +35,7 @@ function main(conf) {
      message = Buffer.alloc(conf.len, 'b');
      break;
    default:
-      throw new Error('unknown message type: ' + conf.type);
+      throw new Error(`unknown message type: ${conf.type}`);
  }

  var fn = api === 'stream' ? streamWrite : legacyWrite;
--- a/benchmark/crypto/rsa-encrypt-decrypt-throughput.js
+++ b/benchmark/crypto/rsa-encrypt-decrypt-throughput.js
@ -10,10 +10,10 @@ var RSA_PublicPem = {};
 var RSA_PrivatePem = {};

 keylen_list.forEach(function(key) {
-  RSA_PublicPem[key] = fs.readFileSync(fixtures_keydir +
-                                       '/rsa_public_' + key + '.pem');
-  RSA_PrivatePem[key] = fs.readFileSync(fixtures_keydir +
-                                        '/rsa_private_' + key + '.pem');
+  RSA_PublicPem[key] =
+    fs.readFileSync(`${fixtures_keydir}/rsa_public_${key}.pem`);
+  RSA_PrivatePem[key] =
+    fs.readFileSync(`${fixtures_keydir}/rsa_private_${key}.pem`);
 });

 var bench = common.createBenchmark(main, {
--- a/benchmark/crypto/rsa-sign-verify-throughput.js
+++ b/benchmark/crypto/rsa-sign-verify-throughput.js
@ -10,10 +10,10 @@ var RSA_PublicPem = {};
 var RSA_PrivatePem = {};

 keylen_list.forEach(function(key) {
-  RSA_PublicPem[key] = fs.readFileSync(fixtures_keydir +
-                                       '/rsa_public_' + key + '.pem');
-  RSA_PrivatePem[key] = fs.readFileSync(fixtures_keydir +
-                                        '/rsa_private_' + key + '.pem');
+  RSA_PublicPem[key] =
+    fs.readFileSync(`${fixtures_keydir}/rsa_public_${key}.pem`);
+  RSA_PrivatePem[key] =
+    fs.readFileSync(`${fixtures_keydir}/rsa_private_${key}.pem`);
 });

 var bench = common.createBenchmark(main, {
--- a/benchmark/es/map-bench.js
+++ b/benchmark/es/map-bench.js
@ -16,11 +16,11 @@ function runObject(n) {
  var i = 0;
  bench.start();
  for (; i < n; i++) {
-    m['i' + i] = i;
-    m['s' + i] = String(i);
-    assert.strictEqual(String(m['i' + i]), m['s' + i]);
-    m['i' + i] = undefined;
-    m['s' + i] = undefined;
+    m[`i${i}`] = i;
+    m[`s${i}`] = String(i);
+    assert.strictEqual(String(m[`i${i}`]), m[`s${i}`]);
+    m[`i${i}`] = undefined;
+    m[`s${i}`] = undefined;
  }
  bench.end(n / 1e6);
 }
@ -30,11 +30,11 @@ function runNullProtoObject(n) {
  var i = 0;
  bench.start();
  for (; i < n; i++) {
-    m['i' + i] = i;
-    m['s' + i] = String(i);
-    assert.strictEqual(String(m['i' + i]), m['s' + i]);
-    m['i' + i] = undefined;
-    m['s' + i] = undefined;
+    m[`i${i}`] = i;
+    m[`s${i}`] = String(i);
+    assert.strictEqual(String(m[`i${i}`]), m[`s${i}`]);
+    m[`i${i}`] = undefined;
+    m[`s${i}`] = undefined;
  }
  bench.end(n / 1e6);
 }
@ -44,11 +44,11 @@ function runNullProtoLiteralObject(n) {
  var i = 0;
  bench.start();
  for (; i < n; i++) {
-    m['i' + i] = i;
-    m['s' + i] = String(i);
-    assert.strictEqual(String(m['i' + i]), m['s' + i]);
-    m['i' + i] = undefined;
-    m['s' + i] = undefined;
+    m[`i${i}`] = i;
+    m[`s${i}`] = String(i);
+    assert.strictEqual(String(m[`i${i}`]), m[`s${i}`]);
+    m[`i${i}`] = undefined;
+    m[`s${i}`] = undefined;
  }
  bench.end(n / 1e6);
 }
@ -61,11 +61,11 @@ function runStorageObject(n) {
  var i = 0;
  bench.start();
  for (; i < n; i++) {
-    m['i' + i] = i;
-    m['s' + i] = String(i);
-    assert.strictEqual(String(m['i' + i]), m['s' + i]);
-    m['i' + i] = undefined;
-    m['s' + i] = undefined;
+    m[`i${i}`] = i;
+    m[`s${i}`] = String(i);
+    assert.strictEqual(String(m[`i${i}`]), m[`s${i}`]);
+    m[`i${i}`] = undefined;
+    m[`s${i}`] = undefined;
  }
  bench.end(n / 1e6);
 }
@ -73,10 +73,10 @@ function runStorageObject(n) {
 function fakeMap() {
  const m = {};
  return {
-    get(key) { return m['$' + key]; },
-    set(key, val) { m['$' + key] = val; },
+    get(key) { return m[`$${key}`]; },
+    set(key, val) { m[`$${key}`] = val; },
    get size() { return Object.keys(m).length; },
-    has(key) { return Object.prototype.hasOwnProperty.call(m, '$' + key); }
+    has(key) { return Object.prototype.hasOwnProperty.call(m, `$${key}`); }
  };
 }

@ -85,11 +85,11 @@ function runFakeMap(n) {
  var i = 0;
  bench.start();
  for (; i < n; i++) {
-    m.set('i' + i, i);
-    m.set('s' + i, String(i));
-    assert.strictEqual(String(m.get('i' + i)), m.get('s' + i));
-    m.set('i' + i, undefined);
-    m.set('s' + i, undefined);
+    m.set(`i${i}`, i);
+    m.set(`s${i}`, String(i));
+    assert.strictEqual(String(m.get(`i${i}`)), m.get(`s${i}`));
+    m.set(`i${i}`, undefined);
+    m.set(`s${i}`, undefined);
  }
  bench.end(n / 1e6);
 }
@ -99,11 +99,11 @@ function runMap(n) {
  var i = 0;
  bench.start();
  for (; i < n; i++) {
-    m.set('i' + i, i);
-    m.set('s' + i, String(i));
-    assert.strictEqual(String(m.get('i' + i)), m.get('s' + i));
-    m.set('i' + i, undefined);
-    m.set('s' + i, undefined);
+    m.set(`i${i}`, i);
+    m.set(`s${i}`, String(i));
+    assert.strictEqual(String(m.get(`i${i}`)), m.get(`s${i}`));
+    m.set(`i${i}`, undefined);
+    m.set(`s${i}`, undefined);
  }
  bench.end(n / 1e6);
 }
--- a/benchmark/fs/bench-realpath.js
+++ b/benchmark/fs/bench-realpath.js
@ -22,7 +22,7 @@ function main(conf) {
  else if (type === 'resolved')
    resolvedPath(n);
  else
-    throw new Error('unknown "type": ' + type);
+    throw new Error(`unknown "type": ${type}`);
 }

 function relativePath(n) {
--- a/benchmark/fs/bench-realpathSync.js
+++ b/benchmark/fs/bench-realpathSync.js
@ -24,7 +24,7 @@ function main(conf) {
  else if (type === 'resolved')
    resolvedPath(n);
  else
-    throw new Error('unknown "type": ' + type);
+    throw new Error(`unknown "type": ${type}`);
  bench.end(n);
 }

--- a/benchmark/http/_chunky_http_client.js
+++ b/benchmark/http/_chunky_http_client.js
@ -37,7 +37,7 @@ function main(conf) {
    for (var i = 0; i < extra_header_count; i++) {
      // Utilize first three powers of a small integer for an odd cycle and
      // because the fourth power of some integers overloads the server.
-      todo.push('X-Header-' + i + ': ' + headers[i % 3]);
+      todo.push(`X-Header-${i}: ${headers[i % 3]}`);
    }
    todo.push('');
    todo.push('');
--- a/benchmark/http/cluster.js
+++ b/benchmark/http/cluster.js
@ -27,7 +27,7 @@ function main(conf) {
      return;

    setTimeout(function() {
-      var path = '/' + conf.type + '/' + conf.len;
+      var path = `/${conf.type}/${conf.len}`;

      bench.http({
        path: path,
--- a/benchmark/http/http_server_for_chunky_client.js
+++ b/benchmark/http/http_server_for_chunky_client.js
@ -6,7 +6,7 @@ var fs = require('fs');
 var fork = require('child_process').fork;
 var common = require('../common.js');
 var test = require('../../test/common.js');
-var pep = path.dirname(process.argv[1]) + '/_chunky_http_client.js';
+var pep = `${path.dirname(process.argv[1])}/_chunky_http_client.js`;
 var PIPE = test.PIPE;

 try {
@ -30,7 +30,7 @@ server = http.createServer(function(req, res) {
 });

 server.on('error', function(err) {
-  throw new Error('server error: ' + err);
+  throw new Error(`server error: ${err}`);
 });

 server.listen(PIPE);
--- a/benchmark/http/simple.js
+++ b/benchmark/http/simple.js
@ -16,8 +16,7 @@ function main(conf) {
  var server = require('../fixtures/simple-http-server.js')
  .listen(process.env.PORT || common.PORT)
  .on('listening', function() {
-    var path = '/' + conf.type + '/' + conf.len + '/' + conf.chunks + '/' +
-               conf.res;
+    var path = `/${conf.type}/${conf.len}/${conf.chunks}/${conf.res}`;

    bench.http({
      path: path,
--- a/benchmark/misc/console.js
+++ b/benchmark/misc/console.js
@ -21,7 +21,7 @@ var bench = common.createBenchmark(main, {
 const nullStream = createNullStream();

 function usingRestAndConcat(...args) {
-  nullStream.write('this is ' + args[0] + ' of ' + args[1] + '\n');
+  nullStream.write(`this is ${args[0]} of ${args[1]}\n`);
 }

 function usingRestAndSpreadTS(...args) {
@ -37,15 +37,15 @@ function usingArgumentsAndApplyTS() {
 }

 function usingRestAndSpreadC(...args) {
-  nullStream.write(util.format(...args) + '\n');
+  nullStream.write(`${util.format(...args)}\n`);
 }

 function usingRestAndApplyC(...args) {
-  nullStream.write(util.format.apply(null, args) + '\n');
+  nullStream.write(`${util.format.apply(null, args)}\n`);
 }

 function usingArgumentsAndApplyC() {
-  nullStream.write(util.format.apply(null, arguments) + '\n');
+  nullStream.write(`${util.format.apply(null, arguments)}\n`);
 }

 function runUsingRestAndConcat(n) {
--- a/benchmark/misc/v8-bench.js
+++ b/benchmark/misc/v8-bench.js
@ -9,8 +9,8 @@ var dir = path.join(__dirname, '..', '..', 'deps', 'v8', 'benchmarks');

 function load(filename, inGlobal) {
  var source = fs.readFileSync(path.join(dir, filename), 'utf8');
-  if (!inGlobal) source = '(function () {' + source + '\n})()';
-  vm.runInThisContext(source, { filename: 'v8/bechmark/' + filename });
+  if (!inGlobal) source = `(function () {${source}\n})()`;
+  vm.runInThisContext(source, { filename: `v8/bechmark/${filename}` });
 }

 load('base.js', true);
@ -41,13 +41,13 @@ global.BenchmarkSuite.RunSuites({
    });
  },
  NotifyError: function(name, error) {
-    console.error(name + ': ' + error);
+    console.error(`${name}: ${error}`);
  },
  NotifyScore: function(score) {
    common.sendResult({
      name: benchmark_name,
      conf: {
-        benchmark: 'Score (version ' + global.BenchmarkSuite.version + ')'
+        benchmark: `Score (version ${global.BenchmarkSuite.version})`
      },
      rate: score,
      time: 0
--- a/benchmark/module/module-loader.js
+++ b/benchmark/module/module-loader.js
@ -20,13 +20,13 @@ function main(conf) {
  try { fs.mkdirSync(benchmarkDirectory); } catch (e) {}

  for (var i = 0; i <= n; i++) {
-    fs.mkdirSync(benchmarkDirectory + i);
+    fs.mkdirSync(`${benchmarkDirectory}${i}`);
    fs.writeFileSync(
-      benchmarkDirectory + i + '/package.json',
+      `${benchmarkDirectory}${i}/package.json`,
      '{"main": "index.js"}'
    );
    fs.writeFileSync(
-      benchmarkDirectory + i + '/index.js',
+      `${benchmarkDirectory}${i}/index.js`,
      'module.exports = "";'
    );
  }
@ -43,12 +43,12 @@ function measureFull(n, useCache) {
  var i;
  if (useCache) {
    for (i = 0; i <= n; i++) {
-      require(benchmarkDirectory + i + '/index.js');
+      require(`${benchmarkDirectory}${i}/index.js`);
    }
  }
  bench.start();
  for (i = 0; i <= n; i++) {
-    require(benchmarkDirectory + i + '/index.js');
+    require(`${benchmarkDirectory}${i}/index.js`);
  }
  bench.end(n / 1e3);
 }
@ -57,12 +57,12 @@ function measureDir(n, useCache) {
  var i;
  if (useCache) {
    for (i = 0; i <= n; i++) {
-      require(benchmarkDirectory + i);
+      require(`${benchmarkDirectory}${i}`);
    }
  }
  bench.start();
  for (i = 0; i <= n; i++) {
-    require(benchmarkDirectory + i);
+    require(`${benchmarkDirectory}${i}`);
  }
  bench.end(n / 1e3);
 }
--- a/benchmark/net/net-c2s-cork.js
+++ b/benchmark/net/net-c2s-cork.js
@ -34,7 +34,7 @@ function main(conf) {
      chunk = 'x'.repeat(len);
      break;
    default:
-      throw new Error('invalid type: ' + type);
+      throw new Error(`invalid type: ${type}`);
  }

  server();
--- a/benchmark/net/net-c2s.js
+++ b/benchmark/net/net-c2s.js
@ -34,7 +34,7 @@ function main(conf) {
      chunk = 'x'.repeat(len);
      break;
    default:
-      throw new Error('invalid type: ' + type);
+      throw new Error(`invalid type: ${type}`);
  }

  server();
--- a/benchmark/net/net-pipe.js
+++ b/benchmark/net/net-pipe.js
@ -34,7 +34,7 @@ function main(conf) {
      chunk = 'x'.repeat(len);
      break;
    default:
-      throw new Error('invalid type: ' + type);
+      throw new Error(`invalid type: ${type}`);
  }

  server();
--- a/benchmark/net/net-s2c.js
+++ b/benchmark/net/net-s2c.js
@ -34,7 +34,7 @@ function main(conf) {
      chunk = 'x'.repeat(len);
      break;
    default:
-      throw new Error('invalid type: ' + type);
+      throw new Error(`invalid type: ${type}`);
  }

  server();
--- a/benchmark/net/tcp-raw-c2s.js
+++ b/benchmark/net/tcp-raw-c2s.js
@ -89,7 +89,7 @@ function client() {
      chunk = 'x'.repeat(len);
      break;
    default:
-      throw new Error('invalid type: ' + type);
+      throw new Error(`invalid type: ${type}`);
  }

  var clientHandle = new TCP();
--- a/benchmark/net/tcp-raw-pipe.js
+++ b/benchmark/net/tcp-raw-pipe.js
@ -86,7 +86,7 @@ function client() {
      chunk = 'x'.repeat(len);
      break;
    default:
-      throw new Error('invalid type: ' + type);
+      throw new Error(`invalid type: ${type}`);
  }

  var clientHandle = new TCP();
--- a/benchmark/net/tcp-raw-s2c.js
+++ b/benchmark/net/tcp-raw-s2c.js
@ -60,7 +60,7 @@ function server() {
        chunk = 'x'.repeat(len);
        break;
      default:
-        throw new Error('invalid type: ' + type);
+        throw new Error(`invalid type: ${type}`);
    }

    clientHandle.readStart();
--- a/benchmark/path/basename-posix.js
+++ b/benchmark/path/basename-posix.js
@ -21,7 +21,7 @@ var bench = common.createBenchmark(main, {
 function main(conf) {
  var n = +conf.n;
  var p = path.posix;
-  var input = '' + conf.pathext;
+  var input = String(conf.pathext);
  var ext;
  var extIdx = input.indexOf('|');
  if (extIdx !== -1) {
--- a/benchmark/path/basename-win32.js
+++ b/benchmark/path/basename-win32.js
@ -21,7 +21,7 @@ var bench = common.createBenchmark(main, {
 function main(conf) {
  var n = +conf.n;
  var p = path.win32;
-  var input = '' + conf.pathext;
+  var input = String(conf.pathext);
  var ext;
  var extIdx = input.indexOf('|');
  if (extIdx !== -1) {
--- a/benchmark/path/dirname-posix.js
+++ b/benchmark/path/dirname-posix.js
@ -18,7 +18,7 @@ var bench = common.createBenchmark(main, {
 function main(conf) {
  var n = +conf.n;
  var p = path.posix;
-  var input = '' + conf.path;
+  var input = String(conf.path);

  bench.start();
  for (var i = 0; i < n; i++) {
--- a/benchmark/path/dirname-win32.js
+++ b/benchmark/path/dirname-win32.js
@ -18,7 +18,7 @@ var bench = common.createBenchmark(main, {
 function main(conf) {
  var n = +conf.n;
  var p = path.win32;
-  var input = '' + conf.path;
+  var input = String(conf.path);

  bench.start();
  for (var i = 0; i < n; i++) {
--- a/benchmark/path/extname-posix.js
+++ b/benchmark/path/extname-posix.js
@ -21,7 +21,7 @@ var bench = common.createBenchmark(main, {
 function main(conf) {
  var n = +conf.n;
  var p = path.posix;
-  var input = '' + conf.path;
+  var input = String(conf.path);

  bench.start();
  for (var i = 0; i < n; i++) {
--- a/benchmark/path/extname-win32.js
+++ b/benchmark/path/extname-win32.js
@ -21,7 +21,7 @@ var bench = common.createBenchmark(main, {
 function main(conf) {
  var n = +conf.n;
  var p = path.win32;
-  var input = '' + conf.path;
+  var input = String(conf.path);

  bench.start();
  for (var i = 0; i < n; i++) {
--- a/benchmark/path/format-posix.js
+++ b/benchmark/path/format-posix.js
@ -12,7 +12,7 @@ var bench = common.createBenchmark(main, {
 function main(conf) {
  var n = +conf.n;
  var p = path.posix;
-  var props = ('' + conf.props).split('|');
+  var props = String(conf.props).split('|');
  var obj = {
    root: props[0] || '',
    dir: props[1] || '',
--- a/benchmark/path/format-win32.js
+++ b/benchmark/path/format-win32.js
@ -12,7 +12,7 @@ var bench = common.createBenchmark(main, {
 function main(conf) {
  var n = +conf.n;
  var p = path.win32;
-  var props = ('' + conf.props).split('|');
+  var props = String(conf.props).split('|');
  var obj = {
    root: props[0] || '',
    dir: props[1] || '',
--- a/benchmark/path/isAbsolute-posix.js
+++ b/benchmark/path/isAbsolute-posix.js
@ -16,7 +16,7 @@ var bench = common.createBenchmark(main, {
 function main(conf) {
  var n = +conf.n;
  var p = path.posix;
-  var input = '' + conf.path;
+  var input = String(conf.path);

  bench.start();
  for (var i = 0; i < n; i++) {
--- a/benchmark/path/isAbsolute-win32.js
+++ b/benchmark/path/isAbsolute-win32.js
@ -17,7 +17,7 @@ var bench = common.createBenchmark(main, {
 function main(conf) {
  var n = +conf.n;
  var p = path.win32;
-  var input = '' + conf.path;
+  var input = String(conf.path);

  bench.start();
  for (var i = 0; i < n; i++) {
--- a/benchmark/path/join-posix.js
+++ b/benchmark/path/join-posix.js
@ -12,7 +12,7 @@ var bench = common.createBenchmark(main, {
 function main(conf) {
  var n = +conf.n;
  var p = path.posix;
-  var args = ('' + conf.paths).split('|');
+  var args = String(conf.paths).split('|');

  bench.start();
  for (var i = 0; i < n; i++) {
--- a/benchmark/path/join-win32.js
+++ b/benchmark/path/join-win32.js
@ -12,7 +12,7 @@ var bench = common.createBenchmark(main, {
 function main(conf) {
  var n = +conf.n;
  var p = path.win32;
-  var args = ('' + conf.paths).split('|');
+  var args = String(conf.paths).split('|');

  bench.start();
  for (var i = 0; i < n; i++) {
--- a/benchmark/path/makeLong-win32.js
+++ b/benchmark/path/makeLong-win32.js
@ -15,7 +15,7 @@ var bench = common.createBenchmark(main, {
 function main(conf) {
  var n = +conf.n;
  var p = path.win32;
-  var input = '' + conf.path;
+  var input = String(conf.path);

  bench.start();
  for (var i = 0; i < n; i++) {
--- a/benchmark/path/normalize-posix.js
+++ b/benchmark/path/normalize-posix.js
@ -17,7 +17,7 @@ var bench = common.createBenchmark(main, {
 function main(conf) {
  var n = +conf.n;
  var p = path.posix;
-  var input = '' + conf.path;
+  var input = String(conf.path);

  bench.start();
  for (var i = 0; i < n; i++) {
--- a/benchmark/path/normalize-win32.js
+++ b/benchmark/path/normalize-win32.js
@ -17,7 +17,7 @@ var bench = common.createBenchmark(main, {
 function main(conf) {
  var n = +conf.n;
  var p = path.win32;
-  var input = '' + conf.path;
+  var input = String(conf.path);

  bench.start();
  for (var i = 0; i < n; i++) {
--- a/benchmark/path/parse-posix.js
+++ b/benchmark/path/parse-posix.js
@ -18,7 +18,7 @@ var bench = common.createBenchmark(main, {
 function main(conf) {
  var n = +conf.n;
  var p = path.posix;
-  var input = '' + conf.path;
+  var input = String(conf.path);

  for (var i = 0; i < n; i++) {
    p.parse(input);
--- a/benchmark/path/parse-win32.js
+++ b/benchmark/path/parse-win32.js
@ -19,7 +19,7 @@ var bench = common.createBenchmark(main, {
 function main(conf) {
  var n = +conf.n;
  var p = path.win32;
-  var input = '' + conf.path;
+  var input = String(conf.path);

  for (var i = 0; i < n; i++) {
    p.parse(input);
--- a/benchmark/path/relative-posix.js
+++ b/benchmark/path/relative-posix.js
@ -18,7 +18,7 @@ var bench = common.createBenchmark(main, {
 function main(conf) {
  var n = +conf.n;
  var p = path.posix;
-  var from = '' + conf.paths;
+  var from = String(conf.paths);
  var to = '';
  var delimIdx = from.indexOf('|');
  if (delimIdx > -1) {
--- a/benchmark/path/relative-win32.js
+++ b/benchmark/path/relative-win32.js
@ -16,7 +16,7 @@ var bench = common.createBenchmark(main, {
 function main(conf) {
  var n = +conf.n;
  var p = path.win32;
-  var from = '' + conf.paths;
+  var from = String(conf.paths);
  var to = '';
  var delimIdx = from.indexOf('|');
  if (delimIdx > -1) {
--- a/benchmark/path/resolve-posix.js
+++ b/benchmark/path/resolve-posix.js
@ -15,7 +15,7 @@ var bench = common.createBenchmark(main, {
 function main(conf) {
  var n = +conf.n;
  var p = path.posix;
-  var args = ('' + conf.paths).split('|');
+  var args = String(conf.paths).split('|');

  bench.start();
  for (var i = 0; i < n; i++) {
--- a/benchmark/path/resolve-win32.js
+++ b/benchmark/path/resolve-win32.js
@ -15,7 +15,7 @@ var bench = common.createBenchmark(main, {
 function main(conf) {
  var n = +conf.n;
  var p = path.win32;
-  var args = ('' + conf.paths).split('|');
+  var args = String(conf.paths).split('|');

  bench.start();
  for (var i = 0; i < n; i++) {
--- a/benchmark/run.js
+++ b/benchmark/run.js
@ -50,7 +50,7 @@ if (format === 'csv') {
    // Construct configuration string, " A=a, B=b, ..."
    let conf = '';
    for (const key of Object.keys(data.conf)) {
-      conf += ' ' + key + '=' + JSON.stringify(data.conf[key]);
+      conf += ` ${key}=${JSON.stringify(data.conf[key])}`;
    }
    // delete first space of the configuration
    conf = conf.slice(1);
--- a/benchmark/scatter.js
+++ b/benchmark/scatter.js
@ -34,7 +34,7 @@ function csvEncodeValue(value) {
  if (typeof value === 'number') {
    return value.toString();
  } else {
-    return '"' + value.replace(/"/g, '""') + '"';
+    return `"${value.replace(/"/g, '""')}"`;
  }
 }

--- a/benchmark/timers/timers-cancel-unpooled.js
+++ b/benchmark/timers/timers-cancel-unpooled.js
@ -22,5 +22,5 @@ function main(conf) {
 }

 function cb() {
-  assert(false, 'Timer ' + this._idleTimeout + ' should not call callback');
+  assert(false, `Timer ${this._idleTimeout} should not call callback`);
 }
--- a/benchmark/timers/timers-insert-unpooled.js
+++ b/benchmark/timers/timers-insert-unpooled.js
@ -23,5 +23,5 @@ function main(conf) {
 }

 function cb() {
-  assert(false, 'Timer ' + this._idleTimeout + ' should not call callback');
+  assert(false, `Timer ${this._idleTimeout} should not call callback`);
 }
--- a/benchmark/tls/throughput.js
+++ b/benchmark/tls/throughput.js
@ -38,9 +38,9 @@ function main(conf) {
  }

  options = {
-    key: fs.readFileSync(cert_dir + '/test_key.pem'),
-    cert: fs.readFileSync(cert_dir + '/test_cert.pem'),
-    ca: [ fs.readFileSync(cert_dir + '/test_ca.pem') ],
+    key: fs.readFileSync(`${cert_dir}/test_key.pem`),
+    cert: fs.readFileSync(`${cert_dir}/test_cert.pem`),
+    ca: [ fs.readFileSync(`${cert_dir}/test_ca.pem`) ],
    ciphers: 'AES256-GCM-SHA384'
  };

--- a/benchmark/tls/tls-connect.js
+++ b/benchmark/tls/tls-connect.js
@ -22,9 +22,9 @@ function main(conf) {

  var cert_dir = path.resolve(__dirname, '../../test/fixtures');
  var options = {
-    key: fs.readFileSync(cert_dir + '/test_key.pem'),
-    cert: fs.readFileSync(cert_dir + '/test_cert.pem'),
-    ca: [ fs.readFileSync(cert_dir + '/test_ca.pem') ],
+    key: fs.readFileSync(`${cert_dir}/test_key.pem`),
+    cert: fs.readFileSync(`${cert_dir}/test_cert.pem`),
+    ca: [ fs.readFileSync(`${cert_dir}/test_ca.pem`) ],
    ciphers: 'AES256-GCM-SHA384'
  };

--- a/benchmark/url/legacy-vs-whatwg-url-get-prop.js
+++ b/benchmark/url/legacy-vs-whatwg-url-get-prop.js
@ -48,7 +48,7 @@ function useWHATWG(n, input) {
  var obj = new URL(input);
  var noDead = {
    protocol: obj.protocol,
-    auth: obj.username + ':' + obj.password,
+    auth: `${obj.username}:${obj.password}`,
    host: obj.host,
    hostname: obj.hostname,
    port: obj.port,
@ -59,7 +59,7 @@ function useWHATWG(n, input) {
  bench.start();
  for (var i = 0; i < n; i += 1) {
    noDead.protocol = obj.protocol;
-    noDead.auth = obj.username + ':' + obj.password;
+    noDead.auth = `${obj.username}:${obj.password}`;
    noDead.host = obj.host;
    noDead.hostname = obj.hostname;
    noDead.port = obj.port;