test: add test for Postgre error message

Author: kenjis

tests/system/Database/Live/Postgre/ConnectTest.php

@@ -0,0 +1,55 @@
+<?php
+
+declare(strict_types=1);
+
+/**
+ * This file is part of CodeIgniter 4 framework.
+ *
+ * (c) CodeIgniter Foundation <admin@codeigniter.com>
+ *
+ * For the full copyright and license information, please view
+ * the LICENSE file that was distributed with this source code.
+ */
+
+namespace CodeIgniter\Database\Live\Postgre;
+
+use CodeIgniter\Database\Exceptions\DatabaseException;
+use CodeIgniter\Test\CIUnitTestCase;
+use Config\Database;
+use PHPUnit\Framework\Attributes\Group;
+
+/**
+ * @internal
+ */
+#[Group('DatabaseLive')]
+final class ConnectTest extends CIUnitTestCase
+{
+    protected function setUp(): void
+    {
+        parent::setUp();
+
+        $this->db = Database::connect($this->DBGroup);
+
+        if ($this->db->DBDriver !== 'Postgre') {
+            $this->markTestSkipped('This test is only for Postgre.');
+        }
+    }
+
+    public function testShowErrorMessageWhenSettingInvalidCharset(): void
+    {
+        $this->expectException(DatabaseException::class);
+        $this->expectExceptionMessage(
+            'Unable to connect to the database.
+Main connection [Postgre]: ERROR:  invalid value for parameter "client_encoding": "utf8mb4"'
+        );
+
+        $config = config('Database');
+        $group  = $config->tests;
+        // Sets invalid charset.
+        $group['charset'] = 'utf8mb4';
+        $db               = Database::connect($group);
+
+        // Actually connect to DB.
+        $db->initialize();
+    }
+}