PhpCsFixer\Fixer\Alias\NoMixedEchoPrintFixer::configure PHP Method

    public function configure(array $configuration = null)
    {
        if (null === $configuration) {
            $configuration = self::$defaultConfig;
        } else {
            if (1 !== count($configuration) || !array_key_exists('use', $configuration) || !in_array($configuration['use'], array('print', 'echo'), true)) {
                throw new InvalidFixerConfigurationException($this->getName(), sprintf('Expected array of element "use" with value "echo" or "print", got "%s".', var_export($configuration, true)));
            }
        }
        $this->resolveConfig($configuration);
    }