Fix the order of received commands. Close #91

Changelog.md

@@ -2,6 +2,8 @@
 
 ### Master Branch
 
+* Fix the order of received commands([#91](https://github.com/luin/ioredis/issues/91)).
+
 ### v1.5.11 - July 7, 2015
 
 * Allow omitting callback in `exec`.

lib/pipeline.js

@@ -147,6 +147,7 @@ Pipeline.prototype.sendCommand = function (command) {
   var position = this._queue.length;
 
   var _this = this;
+
   command.promise.then(function (result) {
     _this.fillResult([null, result], position);
   }).catch(function (error) {
@@ -219,27 +220,25 @@ Pipeline.prototype.exec = function (callback) {
     pipelineSlot = Math.random() * 16384 | 0;
   }
 
-  var promise;
   var _this = this;
-  if (scripts.length) {
-    promise = this.redis.script('exists', scripts.map(function (item) {
-      return item.sha;
-    })).then(function (results) {
-      var pending = [];
-      for (var i = 0; i < results.length; ++i) {
-        if (!results[i]) {
-          pending.push(scripts[i]);
-        }
-      }
-      return Promise.all(pending.map(function (script) {
-        return _this.redis.script('load', script.lua);
-      }));
-    });
-  } else {
-    promise = Promise.resolve();
+  if (!scripts.length) {
+    return execPipeline();
   }
+  return this.redis.script('exists', scripts.map(function (item) {
+    return item.sha;
+  })).then(function (results) {
+    var pending = [];
+    for (var i = 0; i < results.length; ++i) {
+      if (!results[i]) {
+        pending.push(scripts[i]);
+      }
+    }
+    return Promise.all(pending.map(function (script) {
+      return _this.redis.script('load', script.lua);
+    }));
+  }).then(execPipeline);
 
-  return promise.then(function () {
+  function execPipeline () {
     var data = '';
     var writePending = _this.replyPending =  _this._queue.length;
 
@@ -282,7 +281,7 @@ Pipeline.prototype.exec = function (callback) {
       _this.redis.sendCommand(_this._queue[i], stream, node);
     }
     return _this.promise;
-  });
+  }
 };
 
 module.exports = Pipeline;