[WIP] replace async with bluebird promise

lib/portscanner.js

@@ -1,8 +1,12 @@
 var net = require('net')
 var Socket = net.Socket
-var async = require('async')
+var Promise = require('bluebird')
 var promisify = require('./promisify')
 
+Promise.config({
+  cancellation: true
+})
+
 /**
  * Finds the first port with a status of 'open', implying the port is in use and
  * there is likely a service listening on it.
@@ -188,40 +192,30 @@ function findAPortWithStatus (status) {
 
   endPort = endPort || 65535
 
-  var foundPort = false
-  var numberOfPortsChecked = 0
-  var port = portList ? portList[0] : startPort
-
-  // Returns true if a port with matching status has been found or if checked
-  // the entire range of ports
-  var hasFoundPort = function () {
-    return foundPort || numberOfPortsChecked === (portList ? portList.length : endPort - startPort + 1)
+  if (!portList) {
+    portList = []
+    for (var iPort = startPort; iPort <= endPort; iPort++) {
+      portList.push(iPort)
+    }
   }
 
-  // Checks the status of the port
-  var checkNextPort = function (callback) {
-    checkPortStatus(port, host, function (error, statusOfPort) {
-      numberOfPortsChecked++
-      if (statusOfPort === status) {
-        foundPort = true
-        callback(error)
-      } else {
-        port = portList ? portList[numberOfPortsChecked] : port + 1
-        callback(null)
-      }
+  var promise = Promise.map(portList, function (portToCheck) {
+    return new Promise(function (resolve, reject) {
+      checkPortStatus(portToCheck, host, function (err, statusOfPort) {
+        if (statusOfPort === status) {
+          resolve(portToCheck)
+          promise.cancel()
+          callback(null, portToCheck)
+        } else {
+          resolve(false)
+        }
+      })
     })
-  }
-
-  // Check the status of each port until one with a matching status has been
-  // found or the range of ports has been exhausted
-  async.until(hasFoundPort, checkNextPort, function (error) {
-    if (error) {
-      callback(error, port)
-    } else if (foundPort) {
-      callback(null, port)
-    } else {
-      callback(null, false)
-    }
+  }, {
+    concurrency: 50
+  }).then(function (ports) {
+    ports = ports.filter(Boolean)
+    callback(null, ports[0] || false)
   })
 }
 /**

package.json

@@ -31,7 +31,7 @@
   },
   "main": "./lib/portscanner.js",
   "dependencies": {
-    "async": "1.5.2"
+    "bluebird": "^3.4.6"
   },
   "devDependencies": {
     "ava": "^0.4.2",