RainLab\Translate\Models\Message::makeMessageCode PHP Method

    protected static function makeMessageCode($messageId)
    {
        $separator = '.';
        // Convert all dashes/underscores into separator
        $messageId = preg_replace('![' . preg_quote('_') . '|' . preg_quote('-') . ']+!u', $separator, $messageId);
        // Remove all characters that are not the separator, letters, numbers, or whitespace.
        $messageId = preg_replace('![^' . preg_quote($separator) . '\\pL\\pN\\s]+!u', '', mb_strtolower($messageId));
        // Replace all separator characters and whitespace by a single separator
        $messageId = preg_replace('![' . preg_quote($separator) . '\\s]+!u', $separator, $messageId);
        return Str::limit(trim($messageId, $separator), 250);
    }

 public function testMakeMessageCode()
 {
     $this->assertEquals('hello.world', Message::makeMessageCode('hello world'));
     $this->assertEquals('hello.world', Message::makeMessageCode(' hello world '));
     $this->assertEquals('hello.world', Message::makeMessageCode('hello-world'));
     $this->assertEquals('hello.world', Message::makeMessageCode('hello--world'));
     // casing
     $this->assertEquals('hello.world', Message::makeMessageCode('Hello World'));
     $this->assertEquals('hello.world', Message::makeMessageCode('Hello World!'));
     // underscores
     $this->assertEquals('helloworld', Message::makeMessageCode('hello_world'));
     $this->assertEquals('helloworld', Message::makeMessageCode('hello__world'));
     // length limit
     $veryLongString = str_repeat("10 charstr", 30);
     $this->assertTrue(strlen($veryLongString) > 250);
     $this->assertEquals(253, strlen(Message::makeMessageCode($veryLongString)));
     $this->assertStringEndsWith('...', Message::makeMessageCode($veryLongString));
     // unicode characters
     // brrowered some test cases from Stringy, the library Laravel's
     // `slug()` function depends on
     // https://github.com/danielstjules/Stringy/blob/master/tests/CommonTest.php
     $this->assertEquals('fòô.bàř', Message::makeMessageCode('fòô bàř'));
     $this->assertEquals('ťéśţ', Message::makeMessageCode(' ŤÉŚŢ '));
     $this->assertEquals('φ.ź.3', Message::makeMessageCode('φ = ź = 3'));
     $this->assertEquals('перевірка', Message::makeMessageCode('перевірка'));
     $this->assertEquals('лысая.гора', Message::makeMessageCode('лысая гора'));
     $this->assertEquals('щука', Message::makeMessageCode('щука'));
     $this->assertEquals('foo.漢字', Message::makeMessageCode('foo 漢字'));
     // Chinese
     $this->assertEquals('xin.chào.thế.giới', Message::makeMessageCode('xin chào thế giới'));
     $this->assertEquals('xin.chào.thế.giới', Message::makeMessageCode('XIN CHÀO THẾ GIỚI'));
     $this->assertEquals('đấm.phát.chết.luôn', Message::makeMessageCode('đấm phát chết luôn'));
     $this->assertEquals('foo', Message::makeMessageCode('foo '));
     // no-break space (U+00A0)
     $this->assertEquals('foo', Message::makeMessageCode('foo           '));
     // spaces U+2000 to U+200A
     $this->assertEquals('foo', Message::makeMessageCode('foo '));
     // narrow no-break space (U+202F)
     $this->assertEquals('foo', Message::makeMessageCode('foo '));
     // medium mathematical space (U+205F)
     $this->assertEquals('foo', Message::makeMessageCode('foo　'));
     // ideographic space (U+3000)
 }