Using other Helper's methods in Helper

[SanzhiyevMergen]

Case: In your Helper you need to use your other Helper's methods.
For example, you have common Helper for GraphQL api:

class GraphQL extends Module
{
    protected $queries;

    public function sendRequest($operationName, $variables = ''): void
    {
        $this->REST()->sendPOST(
            $this->_getConfig('api_url'),
            [
                'operationName' => $operationName,
                'query'         => $this->queries[$operationName],
                'variables'     => \json_encode($variables),
            ]
        );
    }

    /**
     * @throws ModuleException
     * @return Module | REST
     */
    public function REST()
    {
        return $this->getModule('REST');
    }

and then you need to use method sendRequest to interact with your GraphQL api.

You are free to use your GraphQL Helper like you use any standard Codeception module:

class Backend extends Module
{
     /**
     * @return Module | GraphQL
     * @throws ModuleException
     */
    public function graphql()
    {
        return $this->getModule('GraphQL');
    }

    /**
     * @param $username
     * @param $password
     * @throws ModuleException
     */
    public function login($username, $password): void
    {
        // any actions you need
        $this->graphql()->sendRequest('login', ['username' => $username, 'password' => $password]);
        // set cookie if you need
    }