provide tests for Request::i18n(), re #4774

Merge request !3568

tests/unit/lib/classes/RequestParametersTest.php

@@ -38,6 +38,9 @@ class RequestParametersTest extends Codeception\Test\Unit
         $_GET['datetime'] = '2025-03-25 17:39:04';
         $_GET['invalid_date'] = 'foobar';
 
+        $_POST['localized'] = 'abc';
+        $_POST['localized_i18n']['en_GB'] = 'def';
+
         $testconfig = new Config([
             'USERNAME_REGULAR_EXPRESSION' => '/^([a-zA-Z0-9_@.-]{4,})$/',
         ]);
@@ -284,6 +287,29 @@ class RequestParametersTest extends Codeception\Test\Unit
         $this->assertFalse($invalid_date);
     }
 
+    /**
+     * @covers Request::i18n
+     */
+    public function testRequestI18n()
+    {
+        $i18n = Request::i18n('localized');
+        $this->assertEquals('abc', $i18n->original());
+        $this->assertEquals('def', $i18n->localized('en_GB'));
+        $this->assertNull($i18n->localized('no_LANG'));
+    }
+
+    /**
+     * @covers Request::i18n
+     */
+    public function testRequestI18nWithDefault()
+    {
+        $default = new I18NString('foo', ['en_GB' => 'bar']);
+
+        $i18n = Request::i18n('unknown', $default);
+        $this->assertEquals('foo', $i18n->original());
+        $this->assertEquals('bar', $i18n->localized('en_GB'));
+    }
+
     public function tearDown(): void
     {
         Config::set(null);