InputStream example

yield 'ping';
            yield 'pong';
        };

        $process = $this->getProcessForCode('stream_copy_to_stream(STDIN, STDOUT);', null, null, $input());
        $process->run();
        $this->assertSame('pingpong', $process->getOutput());
    }

    public function testSimpleInputStream()
    {
        $input = new InputStream();

        $process = $this->getProcessForCode('echo \'ping\'; echo fread(STDIN, 4); echo fread(STDIN, 4);');
        $process->setInput($input);

        $process->start(function D$type, $data) use ($input) {
            if ('ping' === $data) {
                $input->write('pang');
            } elseif (!$input->isClosed()) {
                $input->write('pong');
                $input->close();
            }
        });