Restore helper.promisify so puppeteer-web doesn't break

We can reconsider this once browserify/browserify#1844 gets merged.

experimental/puppeteer-firefox/lib/BrowserFetcher.js

@@ -82,10 +82,10 @@ function downloadURL(product, platform, host, revision) {
   return util.format(downloadURLs[product][platform], host, revision, archiveName(product, platform, revision));
 }
 
-const readdirAsync = util.promisify(fs.readdir.bind(fs));
-const mkdirAsync = util.promisify(fs.mkdir.bind(fs));
-const unlinkAsync = util.promisify(fs.unlink.bind(fs));
-const chmodAsync = util.promisify(fs.chmod.bind(fs));
+const readdirAsync = helper.promisify(fs.readdir.bind(fs));
+const mkdirAsync = helper.promisify(fs.mkdir.bind(fs));
+const unlinkAsync = helper.promisify(fs.unlink.bind(fs));
+const chmodAsync = helper.promisify(fs.chmod.bind(fs));
 
 function existsAsync(filePath) {
   let fulfill = null;

experimental/puppeteer-firefox/lib/Page.js

@@ -4,7 +4,6 @@ const {Dialog} = require('./Dialog');
 const {TimeoutError} = require('./Errors');
 const fs = require('fs');
 const mime = require('mime');
-const util = require('util');
 const EventEmitter = require('events');
 const {createHandle} = require('./JSHandle');
 const {Events} = require('./Events');
@@ -15,7 +14,7 @@ const {TimeoutSettings} = require('./TimeoutSettings');
 const {NavigationWatchdog} = require('./NavigationWatchdog');
 const {Accessibility} = require('./Accessibility');
 
-const writeFileAsync = util.promisify(fs.writeFile);
+const writeFileAsync = helper.promisify(fs.writeFile);
 
 class Page extends EventEmitter {
   /**

experimental/puppeteer-firefox/lib/helper.js

@@ -65,6 +65,26 @@ class Helper {
     }
   }
 
+  /**
+   * @param {function} nodeFunction
+   * @return {function}
+   */
+  static promisify(nodeFunction) {
+    function promisified(...args) {
+      return new Promise((resolve, reject) => {
+        function callback(err, ...result) {
+          if (err)
+            return reject(err);
+          if (result.length === 1)
+            return resolve(result[0]);
+          return resolve(result);
+        }
+        nodeFunction.call(null, ...args, callback);
+      });
+    }
+    return promisified;
+  }
+
   /**
    * @param {!Object} obj
    * @return {boolean}

lib/BrowserFetcher.js

@@ -20,7 +20,7 @@ const path = require('path');
 const util = require('util');
 const extract = require('extract-zip');
 const URL = require('url');
-const {assert} = require('./helper');
+const {helper, assert} = require('./helper');
 const removeRecursive = require('rimraf');
 // @ts-ignore
 const ProxyAgent = require('https-proxy-agent');
@@ -64,10 +64,10 @@ function downloadURL(platform, host, revision) {
   return util.format(downloadURLs[platform], host, revision, archiveName(platform, revision));
 }
 
-const readdirAsync = util.promisify(fs.readdir.bind(fs));
-const mkdirAsync = util.promisify(fs.mkdir.bind(fs));
-const unlinkAsync = util.promisify(fs.unlink.bind(fs));
-const chmodAsync = util.promisify(fs.chmod.bind(fs));
+const readdirAsync = helper.promisify(fs.readdir.bind(fs));
+const mkdirAsync = helper.promisify(fs.mkdir.bind(fs));
+const unlinkAsync = helper.promisify(fs.unlink.bind(fs));
+const chmodAsync = helper.promisify(fs.chmod.bind(fs));
 
 function existsAsync(filePath) {
   let fulfill = null;

lib/DOMWorld.js

@@ -15,11 +15,10 @@
  */
 
 const fs = require('fs');
-const util = require('util');
 const {helper, assert} = require('./helper');
 const {LifecycleWatcher} = require('./LifecycleWatcher');
 const {TimeoutError} = require('./Errors');
-const readFileAsync = util.promisify(fs.readFile);
+const readFileAsync = helper.promisify(fs.readFile);
 
 /**
  * @unrestricted

lib/Launcher.js

@@ -15,7 +15,6 @@
  */
 const os = require('os');
 const path = require('path');
-const util = require('util');
 const http = require('http');
 const https = require('https');
 const URL = require('url');
@@ -31,8 +30,8 @@ const {TimeoutError} = require('./Errors');
 const WebSocketTransport = require('./WebSocketTransport');
 const PipeTransport = require('./PipeTransport');
 
-const mkdtempAsync = util.promisify(fs.mkdtemp);
-const removeFolderAsync = util.promisify(removeFolder);
+const mkdtempAsync = helper.promisify(fs.mkdtemp);
+const removeFolderAsync = helper.promisify(removeFolder);
 
 const CHROME_PROFILE_PATH = path.join(os.tmpdir(), 'puppeteer_dev_profile-');
 

lib/Page.js

@@ -18,7 +18,6 @@ const fs = require('fs');
 const path = require('path');
 const EventEmitter = require('events');
 const mime = require('mime');
-const util = require('util');
 const {Events} = require('./Events');
 const {Connection} = require('./Connection');
 const {Dialog} = require('./Dialog');
@@ -33,7 +32,7 @@ const {createJSHandle} = require('./JSHandle');
 const {Accessibility} = require('./Accessibility');
 const {TimeoutSettings} = require('./TimeoutSettings');
 
-const writeFileAsync = util.promisify(fs.writeFile);
+const writeFileAsync = helper.promisify(fs.writeFile);
 
 class Page extends EventEmitter {
   /**

lib/helper.js

@@ -16,11 +16,6 @@
 const {TimeoutError} = require('./Errors');
 const debugError = require('debug')(`puppeteer:error`);
 const fs = require('fs');
-const util = require('util');
-
-const openAsync = util.promisify(fs.open);
-const writeAsync = util.promisify(fs.write);
-const closeAsync = util.promisify(fs.close);
 
 class Helper {
   /**
@@ -161,6 +156,26 @@ class Helper {
     return typeof obj === 'number' || obj instanceof Number;
   }
 
+  /**
+   * @param {function} nodeFunction
+   * @return {function}
+   */
+  static promisify(nodeFunction) {
+    function promisified(...args) {
+      return new Promise((resolve, reject) => {
+        function callback(err, ...result) {
+          if (err)
+            return reject(err);
+          if (result.length === 1)
+            return resolve(result[0]);
+          return resolve(result);
+        }
+        nodeFunction.call(null, ...args, callback);
+      });
+    }
+    return promisified;
+  }
+
   /**
    * @param {!NodeJS.EventEmitter} emitter
    * @param {(string|symbol)} eventName
@@ -255,6 +270,10 @@ class Helper {
   }
 }
 
+const openAsync = Helper.promisify(fs.open);
+const writeAsync = Helper.promisify(fs.write);
+const closeAsync = Helper.promisify(fs.close);
+
 /**
  * @param {*} value
  * @param {string=} message

test/launcher.spec.js

@@ -16,12 +16,11 @@
 const fs = require('fs');
 const os = require('os');
 const path = require('path');
-const util = require('util');
-
-const rmAsync = util.promisify(require('rimraf'));
-const mkdtempAsync = util.promisify(fs.mkdtemp);
-const readFileAsync = util.promisify(fs.readFile);
-const statAsync = util.promisify(fs.stat);
+const {helper} = require('../lib/helper');
+const rmAsync = helper.promisify(require('rimraf'));
+const mkdtempAsync = helper.promisify(fs.mkdtemp);
+const readFileAsync = helper.promisify(fs.readFile);
+const statAsync = helper.promisify(fs.stat);
 const TMP_FOLDER = path.join(os.tmpdir(), 'pptr_tmp_folder-');
 const utils = require('./utils');