fix: wrong variable and add tests

Author: kenjis

system/Database/BaseBuilder.php

@@ -3066,7 +3066,7 @@ protected function compileSelect($selectOverride = false): string
                 // is because until the user calls the from() function we don't know if there are aliases
                 foreach ($this->QBSelect as $key => $val) {
                     if ($val instanceof RawSql) {
-                        $this->QBSelect[$key] = (string) $this->QBSelect[0];
+                        $this->QBSelect[$key] = (string) $val;
                     } else {
                         $protect              = $this->QBNoEscape[$key] ?? null;
                         $this->QBSelect[$key] = $this->db->protectIdentifiers($val, false, $protect);

tests/system/Database/Builder/SelectTest.php

@@ -19,6 +19,7 @@
 use CodeIgniter\Database\SQLSRV\Builder as SQLSRVBuilder;
 use CodeIgniter\Test\CIUnitTestCase;
 use CodeIgniter\Test\Mock\MockConnection;
+use PHPUnit\Framework\Attributes\DataProvider;
 use PHPUnit\Framework\Attributes\Group;
 
 /**
@@ -67,21 +68,62 @@ public function testSelectAcceptsArray(): void
         $this->assertSame($expected, str_replace("\n", ' ', $builder->getCompiledSelect()));
     }
 
-    public function testSelectAcceptsArrayWithRawSql(): void
+    #[DataProvider('provideSelectAcceptsArrayWithRawSql')]
+    public function testSelectAcceptsArrayWithRawSql(array $select, string $expected): void
     {
         $builder = new BaseBuilder('employees', $this->db);
 
-        $builder->select([
-            new RawSql("IF(salary > 5000, 'High', 'Low') AS salary_level"),
-            'employee_id',
-        ]);
+        $builder->select($select);
 
-        $expected = <<<'SQL'
-            SELECT IF(salary > 5000, 'High', 'Low') AS salary_level, "employee_id" FROM "employees"
-            SQL;
         $this->assertSame($expected, str_replace("\n", ' ', $builder->getCompiledSelect()));
     }
 
+    /**
+     * @return list<list<RawSql|string>|string>
+     */
+    public static function provideSelectAcceptsArrayWithRawSql(): iterable
+    {
+        yield from [
+            [
+                [
+                    new RawSql("IF(salary > 5000, 'High', 'Low') AS salary_level"),
+                    'employee_id',
+                ],
+                <<<'SQL'
+                    SELECT IF(salary > 5000, 'High', 'Low') AS salary_level, "employee_id" FROM "employees"
+                    SQL,
+            ],
+            [
+                [
+                    'employee_id',
+                    new RawSql("IF(salary > 5000, 'High', 'Low') AS salary_level"),
+                ],
+                <<<'SQL'
+                    SELECT "employee_id", IF(salary > 5000, 'High', 'Low') AS salary_level FROM "employees"
+                    SQL,
+            ],
+            [
+                [
+                    new RawSql("CONCAT(first_name, ' ', last_name) AS full_name"),
+                    new RawSql("IF(salary > 5000, 'High', 'Low') AS salary_level"),
+                ],
+                <<<'SQL'
+                    SELECT CONCAT(first_name, ' ', last_name) AS full_name, IF(salary > 5000, 'High', 'Low') AS salary_level FROM "employees"
+                    SQL,
+            ],
+            [
+                [
+                    new RawSql("CONCAT(first_name, ' ', last_name) AS full_name"),
+                    'employee_id',
+                    new RawSql("IF(salary > 5000, 'High', 'Low') AS salary_level"),
+                ],
+                <<<'SQL'
+                    SELECT CONCAT(first_name, ' ', last_name) AS full_name, "employee_id", IF(salary > 5000, 'High', 'Low') AS salary_level FROM "employees"
+                    SQL,
+            ],
+        ];
+    }
+
     public function testSelectAcceptsMultipleColumns(): void
     {
         $builder = new BaseBuilder('users', $this->db);