Adding simple CONCAT() function transformer for Sqlite

lib/Cake/Model/Datasource/Database/Dialect/PostgresDialectTrait.php

@@ -19,7 +19,6 @@
 
 use Cake\Model\Datasource\Database\Expression\UnaryExpression;
 use Cake\Model\Datasource\Database\Query;
-use Cake\Model\Datasource\Database\SqlDialectTrait;
 
 trait PostgresDialectTrait {
 

lib/Cake/Model/Datasource/Database/Dialect/SqliteDialectTrait.php

@@ -0,0 +1,42 @@
+<?php
+/**
+ * PHP Version 5.4
+ *
+ * CakePHP(tm) : Rapid Development Framework (http://cakephp.org)
+ * Copyright (c) Cake Software Foundation, Inc. (http://cakefoundation.org)
+ *
+ * Licensed under The MIT License
+ * For full copyright and license information, please see the LICENSE.txt
+ * Redistributions of files must retain the above copyright notice.
+ *
+ * @copyright     Copyright (c) Cake Software Foundation, Inc. (http://cakefoundation.org)
+ * @link          http://cakephp.org CakePHP(tm) Project
+ * @package       Cake.Model
+ * @since         CakePHP(tm) v 3.0.0
+ * @license       MIT License (http://www.opensource.org/licenses/mit-license.php)
+ */
+namespace Cake\Model\Datasource\Database\Dialect;
+
+use Cake\Model\Datasource\Database\Expression\FunctionExpression;
+use Cake\Model\Datasource\Database\Query;
+
+trait SqliteDialectTrait {
+
+	protected function _selectQueryTranslator($query) {
+		return parent::_selectQueryTranslator($query)
+			->traverseExpressions(function($expression) {
+				if ($expression instanceof FunctionExpression) {
+					$this->_transformFunctionExpression($expression);
+				}
+			});
+	}
+
+	protected function _transformFunctionExpression(FunctionExpression $expression) {
+		if ($expression->name() === 'CONCAT') {
+			// CONCAT function is expressed as exp1 || exp2
+			$expression->name('')->type(' ||');
+		}
+	}
+
+}
+

lib/Cake/Model/Datasource/Database/Driver/Sqlite.php

@@ -18,13 +18,15 @@
 namespace Cake\Model\Datasource\Database\Driver;
 
 use Cake\Model\Datasource\Database\Statement\BufferedStatement;
+use Cake\Model\Datasource\Database\Dialect\SqliteDialectTrait;
 use PDO;
 
 class Sqlite extends \Cake\Model\Datasource\Database\Driver {
 
 	use PDODriverTrait {
 		connect as protected _connect;
 	}
+	use SqliteDialectTrait;
 
 /**
  * Base configuration settings for Sqlite driver

lib/Cake/Model/Datasource/Database/Expression/FunctionExpression.php

@@ -34,7 +34,7 @@ class FunctionExpression extends QueryExpression {
  *
  * ``$f = new FunctionExpression('CONCAT', ['name' => 'literal', ' rules']);``
  *
- * Will produce ``CONCANT(name, ' rules')``
+ * Will produce ``CONCAT(name, ' rules')``
  *
  * @param string $name the name of the function to be constructed
  * @param array $params list of arguments to be passed to the function

lib/Cake/Model/Datasource/Database/Expression/UnaryExpression.php

@@ -20,7 +20,7 @@
 class UnaryExpression extends QueryExpression {
 
 	public function sql() {
-		return $this->_conjunction . ' (' . ((string)current($this->_conditions)) . ')';
+		return $this->_conjunction . ' (' . (string)$this->_conditions[0] . ')';
 	}
 
 }

lib/Cake/Test/TestCase/Model/Datasource/Database/QueryTest.php

@@ -1944,25 +1944,27 @@ public function testInsertFailureMixingTypesQueryFirst() {
 	}
 
 /**
- * undocumented function
+ * Tests that functions are correctly transformed and their parameters are bound
  *
  * @group FunctionExpression
  * @return void
  */
 	public function testSQLFunctions() {
 		$this->_insertTwoRecords();
 		$query = new Query($this->connection);
-		$result = $query->select(function($q) { return ['total' => $q->count('*'), 'title']; })
+		$result = $query->select(function($q) { return ['total' => $q->count('*')]; })
 			->from('articles')
 			->execute();
-		$expected = [['total' => 2, 'title' => 'another title']];
+		$expected = [['total' => 2]];
 		$this->assertEquals($expected, $result->fetchAll('assoc'));
 
 		$query = new Query($this->connection);
-		$result = $query->select([$query->concat(['title' => 'literal', ' is appended'])])
+		$result = $query->select(['c' => $query->concat(['title' => 'literal', ' is appended'])])
 			->from('articles')
+			->order(['c' => 'ASC'])
 			->execute();
-		debug($result->fetchAll());
+		$expected = [['c' => 'a title is appended'], ['c' => 'another title is appended']];
+		$this->assertEquals($expected, $result->fetchAll('assoc'));
 	}