PHP Parse error: syntax error, unexpected ':', expecting ';' or '{'

Question

I am trying to play with php7. I installed https://github.com/rlerdorf/php7dev and connected via phpstorm. I am trying to use a new function like this:

<?php
namespace Kata;

class StringCalculator
{
    public function add(string $parameters): int {
        return 0;
    }
}

then I try to check it like this:

<?php
namespace Kata;

class StringCalculatorTest extends \PHPUnit_Framework_TestCase
{
    public function testAddEmptyString()
    {
        $calc = new StringCalculator();
        $this->assertSame(0, $calc->add(''));
    }
}

and I run with phpunit, unfortunately I have

PHP Parse error: syntax error, unexpected ':', expecting ';' or '{'

I may not have installed php7 correctly, but everything seems to be fine when I php -v

PHP 7.0.0-dev (cli) (Build: May 25, 2015 16:34:33) (DEBUG) Copyright (c) 1997-2015 PHP Group Zend Engine v3.0.0-dev, Copyright (c) 1998-2015 Zend Technologies with Zend OPcache v7.0.6-dev, Copyright (c) 1999-2015, Zend Technologies

UPDATE

/ php7 ( ), , cli, :

<?php
    $calc = new Kata\StringCalculator();
    var_dump($calc->add(''));

int(0) .

phpunit?

Answer 1

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PHP Parse error: syntax error, unexpected ':', expecting ';' or '{'

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public function add(string $parameters): int {

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