public function testPeekToken()
{
$grammar = "comment :== literal .";
$scanner = new Scanner(trim($grammar));
$scanner->nextToken();
$t = $scanner->currentToken();
$this->assertEquals("comment", $t->getValue());
$this->assertEquals(":==", $scanner->peekToken()->getValue());
$scanner->nextToken();
$t = $scanner->currentToken();
$this->assertEquals(":==", $t->getValue());
$this->assertEquals("literal", $scanner->peekToken()->getValue());
$scanner->nextToken();
$t = $scanner->currentToken();
$this->assertEquals("literal", $t->getValue());
$scanner->nextToken();
$t = $scanner->currentToken();
$this->assertEquals(".", $t->getValue());
$scanner->nextToken();
$t = $scanner->currentToken();
$this->assertEquals(Token::EOF, $t->getType());
}
