Determine if a Mink NodeElement contains a specific css rule attribute value.

mink-step-helper-elementhascssvalue.php

/**
 * Determine if a Mink NodeElement contains a specific css rule attribute value.
 *
 * @param NodeElement $element
 *   NodeElement previously selected with $this->getSession()->getPage()->find().
 * @param string $rule
 *   Name of the CSS rule, such as "visibility".
 * @param string $value
 *   Value of the specified rule, such as "hidden".
 *
 * @return NodeElement|bool
 *   The NodeElement selected if true, FALSE otherwise.
 */
protected function elementHasCSSValue($element, $rule, $value)
{
    $exists = FALSE;
    $style = $element->getAttribute('style');
    if ($style) {
        if (preg_match("/(^{$rule}:|; {$rule}:) ([a-z0-9]+);/i", $style, $matches)) {
            $found = array_pop($matches);
            if ($found == $value) {
                $exists = $element;
            }
        }
    }

    return $exists;
}