Fix connection.destroy() on pool connection creating sequences

fixes #1291

Changes.md

@@ -6,6 +6,7 @@ you spot any mistakes.
 
 ## HEAD
 
+* Fix `connection.destroy()` on pool connection creating sequences #1291
 * Fix reading password from MySQL URL that has bare colon #1278
 * Handle MySQL servers not closing TCP connection after QUIT -> OK exchange #1277
 * Minor SqlString Date to string performance improvement #1233

lib/PoolConnection.js

@@ -43,8 +43,8 @@ PoolConnection.prototype.end = function () {
 };
 
 PoolConnection.prototype.destroy = function () {
+  Connection.prototype.destroy.apply(this, arguments);
   this._removeFromPool(this);
-  return Connection.prototype.destroy.apply(this, arguments);
 };
 
 PoolConnection.prototype._removeFromPool = function _removeFromPool() {

test/unit/pool/test-connection-destroy.js

@@ -0,0 +1,27 @@
+var assert     = require('assert');
+var common     = require('../../common');
+var Connection = common.Connection;
+var pool       = common.createPool({port: common.fakeServerPort});
+
+var server = common.createFakeServer();
+
+server.listen(common.fakeServerPort, function (err) {
+  assert.ifError(err);
+
+  pool.getConnection(function (err, connection) {
+    assert.ifError(err);
+    assert.notEqual(connection.state, 'disconnected');
+
+    connection.on('enqueue', function () {
+      throw new Error('Unexpected sequence enqueued after connection destroy');
+    });
+
+    connection.destroy();
+    assert.equal(connection.state, 'disconnected');
+
+    pool.end(function (err) {
+      assert.ifError(err);
+      server.destroy();
+    });
+  });
+});