quack/quack

<?php
/**
 * Quack Compiler and toolkit
 * Copyright (C) 2015-2017 Quack and CONTRIBUTORS
 *
 * This file is part of Quack.
 *
 * Quack is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * Quack is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with Quack.  If not, see <http://www.gnu.org/licenses/>.
 */
namespace QuackCompiler\Ast\Expr;

use \QuackCompiler\Intl\Localization;
use \QuackCompiler\Lexer\Tag;
use \QuackCompiler\Lexer\Token;
use \QuackCompiler\Parser\Parser;
use \QuackCompiler\Scope\Meta;
use \QuackCompiler\Types\TypeError;

class PrefixExpr extends Expr
{
    private $operator;
    private $right;

    public function __construct(Token $operator, Expr $right)
    {
        $this->operator = $operator->getTag();
        $this->right = $right;
    }

    public function format(Parser $parser)
    {
        $source = Tag::T_NOT === $this->operator
            ? 'not '
            : $this->operator;
        $source .= $this->right->format($parser);

        return $this->parenthesize($source);
    }

    public function injectScope($parent_scope)
    {
        $this->scope = $parent_scope;
        $this->right->injectScope($parent_scope);
    }

    public function getType()
    {
        $right_type = $this->right->getType();
        $op_name = Tag::getOperatorLexeme($this->operator);

        $type_error = new TypeError(Localization::message('TYP230', [$op_name, $right_type]));

        switch ($this->operator) {
            case '+':
            case '-':
            case '~':
                if ($right_type->isNumber()) {
                    return $right_type;
                }

                throw $type_error;
            case Tag::T_NOT:
                $bool = $this->scope->getPrimitiveType('Bool');
                if ($bool->check($right_type)) {
                    return $right_type;
                }

                throw $type_error;
        }
    }
}