src/Context/Form/FormContext.php
public function shouldSeeThumbnail()
    {
        $thumb = false;

        foreach (['.upload-preview', '.media-thumbnail img', '.image-preview img'] as $selector) {
            if ($thumb) {
                break;
            }

            $thumb = $this->findByCss($selector);
        }

        if (null === $thumb) {
            throw new \Exception('An expected image tag was not found.');
        }

        $file = explode('?', $thumb->getAttribute('src'));
        $file = reset($file);

        $curl = new CurlService();
        list(, $info) = $curl->execute('GET', $file);

        if (empty($info) || strpos($info['content_type'], 'image/') === false) {
            throw new FileNotFoundException(sprintf('%s did not return an image', $file));
        }
    }
public function shouldSeeThumbnail()
    {
        $thumb = false;

        foreach (['.upload-preview', '.media-thumbnail img', '.image-preview img'] as $selector) {
            if ($thumb) {
                break;
            }

            $thumb = $this->findByCss($selector);
        }

        if (null === $thumb) {
            throw new \Exception('An expected image tag was not found.');
        }

        $file = explode('?', $thumb->getAttribute('src'));
        $file = reset($file);

        $curl = new CurlService();
        list(, $info) = $curl->execute('GET', $file);

        if (empty($info) || strpos($info['content_type'], 'image/') === false) {
            throw new FileNotFoundException(sprintf('%s did not return an image', $file));
        }
    }
Check that an image was uploaded and can be viewed on the page.

@throws \Exception
@throws FileNotFoundException

@Then /^(?:|I )should see the thumbnail$/