Draining the pool after releasing connections may cause write to destroyed stream

lib/connection-pool.js

@@ -265,24 +265,26 @@ ConnectionPool.prototype.release = function(connection) {
     }
 };
 
-ConnectionPool.prototype.drain = function (callback) {
+ConnectionPool.prototype.drain = async function (callback) {
     this.log('draining pool');
     if (this.drained) {//pool has been drained
         if (callback)
             callback();
         return;
     }
 
+    // Flag as drained as this prevent others from acquiring new connections from the pool.
     this.drained = true;
 
+    // Remove all pending acquires.
     for (i = this.waiting.length - 1; i >= 0; i--) {
         var waiter = this.waiting[i];
 
         if (waiter.timeout)
             clearTimeout(waiter.timeout);
     }
 
-    this.waiting = null;
+    this.waiting.length = 0;
 
     var eventTotal = this.connections.length;
     var eventCount = 0;
@@ -302,6 +304,14 @@ ConnectionPool.prototype.drain = function (callback) {
             clearTimeout(pooled.timeout);
 
         if (pooled.con) {
+            if (pooled.con.request) {
+                pooled.con.request.cancel();
+
+                // Make sure no requests are running before closing the connection.
+                while (pooled.con.request) {
+                    await new Promise(done => setTimeout(done, 100));
+                }
+            }
             pooled.con.on('end', ended);
             pooled.con.close();
         } else {

package.json

@@ -1,6 +1,6 @@
 {
   "name": "tedious-connection-pool",
-  "version": "1.0.5",
+  "version": "1.0.6",
   "description": "Connection Pool for tedious.",
   "main": "lib/connection-pool.js",
   "scripts": {
@@ -30,8 +30,8 @@
     }
   ],
   "license": "MIT",
-  "dependencies": {
-    "tedious": "^1.14.0"
+  "peerDependencies": {
+    "tedious": ">= 1.0.0"
   },
   "devDependencies": {
     "mocha": "^3.0.2",