Improve benchmarks accuracy (#148)

* Improve benchmarks accuracy

* Fix test

* Remove plugins from package.json

* Revert parts of benchamrk

* Add best size / best speed

* Add an option to simplify

* Fix linter

* Remove multiPass

* Remove state arg

scripts/benchmark.js

@@ -17,6 +17,8 @@ const compile = require("google-closure-compiler-js").compile;
 
 let packagename, filename;
 
+const NUM_TEST_RUNS = 3;
+
 const script = new Command("benchmark.js")
   .option("-o, --offline", "Only install package if not present; package not removed after testing")
   .usage("[options] <package> [file]")
@@ -35,7 +37,7 @@ if (!packagename) {
 const pathToScripts = __dirname;
 
 const table = new Table({
-  head: ["", "raw", "raw win", "gzip", "gzip win", "parse time", "run"],
+  head: ["", "raw", "raw win", "gzip", "gzip win", "parse time", "run time (average)"],
   chars: {
     top: "",
     "top-mid": "" ,
@@ -100,6 +102,7 @@ function checkFile() {
 }
 
 function test(name, callback) {
+
   console.log("testing", name);
 
   const start = Date.now();
@@ -116,20 +119,39 @@ function test(name, callback) {
   const parseEnd = Date.now();
   const parseNow = parseEnd - parseStart;
 
+  const runTimes = [run];
+
+  for (let i = 1; i < NUM_TEST_RUNS; i++) {
+    const start = Date.now();
+    callback(code);
+    runTimes.push(Date.now() - start);
+  }
+
+  const totalTime = runTimes.reduce((a, b) => a + b, 0);
+  const average = parseInt(totalTime / runTimes.length, 10);
+
   results.push({
     name: name,
     raw: result.length,
     gzip: gzipped.length,
     parse: parseNow,
-    run: run,
+    run: average,
   });
 }
 
 function testFile() {
   code = fs.readFileSync(filename, "utf8");
   gzippedCode = zlib.gzipSync(code);
 
-  test("babili", function (code) {
+  test("babili (best speed)", function (code) {
+    return babel.transform(code, {
+      sourceType: "script",
+      presets: [require("../packages/babel-preset-babili")],
+      comments: false,
+    }).code;
+  });
+
+  test("babili (best size)", function (code) {
     return babel.transform(code, {
       sourceType: "script",
       presets: [require("../packages/babel-preset-babili")],
@@ -161,9 +183,7 @@ function testFile() {
 }
 
 function processResults() {
-  results = results.sort(function (a, b) {
-    return a.gzip > b.gzip;
-  });
+  results = results.sort((a, b) => a.gzip > b.gzip);
 
   results.forEach(function (result, i) {
     let row = [