Add support for using promises in Cursor.read()

Author: Bluenix2

packages/pg-cursor/index.js

@@ -6,6 +6,7 @@ const util = require('util')
 
 let nextUniqueID = 1 // concept borrowed from org.postgresql.core.v3.QueryExecutorImpl
 
+<<<<<<< HEAD
 function Cursor(text, values, config) {
   EventEmitter.call(this)
 
@@ -30,6 +31,25 @@ Cursor.prototype._ifNoData = function () {
   this._shiftQueue()
   if (this.connection) {
     this.connection.removeListener('rowDescription', this._rowDescription)
+=======
+class Cursor extends EventEmitter {
+  constructor(text, values, config) {
+    super()
+
+    this._conf = config || {}
+    this.text = text
+    this.values = values ? values.map(prepare) : null
+    this.connection = null
+    this._queue = []
+    this.state = 'initialized'
+    this._result = new Result(this._conf.rowMode, this._conf.types)
+    this._Promise = this._conf.Promise || global.Promise
+    this._cb = null
+    this._rows = null
+    this._portal = null
+    this._ifNoData = this._ifNoData.bind(this)
+    this._rowDescription = this._rowDescription.bind(this)
+>>>>>>> e800f45 (Add support for using promises in Cursor.read())
   }
 }
 
@@ -216,20 +236,31 @@ Cursor.prototype.close = function (cb) {
   }
 }
 
-Cursor.prototype.read = function (rows, cb) {
-  if (this.state === 'idle' || this.state === 'submitted') {
-    return this._getRows(rows, cb)
-  }
-  if (this.state === 'busy' || this.state === 'initialized') {
-    return this._queue.push([rows, cb])
-  }
-  if (this.state === 'error') {
-    return setImmediate(() => cb(this._error))
-  }
-  if (this.state === 'done') {
-    return setImmediate(() => cb(null, []))
-  } else {
-    throw new Error('Unknown state: ' + this.state)
+  read(rows, cb) {
+    var result
+
+    if (!cb) {
+      result = new this._Promise((resolve, reject) => {
+        cb = (err, rows) => (err ? reject(err) : resolve(rows))
+      })
+    }
+    if (this.state === 'idle' || this.state === 'submitted') {
+      this._getRows(rows, cb)
+    }
+    else if (this.state === 'busy' || this.state === 'initialized') {
+      this._queue.push([rows, cb])
+    }
+    else if (this.state === 'error') {
+      setImmediate(() => cb(this._error))
+    }
+    else if (this.state === 'done') {
+      setImmediate(() => cb(null, []))
+    } else {
+      throw new Error('Unknown state: ' + this.state)
+    }
+
+    // Return the promise (or undefined)
+    return result
   }
 }