Twig/Extension/DataSourceExtension.php
private function getVars(DataSourceViewInterface $dataSource)
    {
        return isset($this->themesVars[$dataSource->getName()])
            ? $this->themesVars[$dataSource->getName()]
            : []
        ;
    }
private function getVars(DataSourceViewInterface $dataSource)
    {
        return isset($this->themesVars[$dataSource->getName()])
            ? $this->themesVars[$dataSource->getName()]
            : []
        ;
    }
private function getVars ( DataSourceViewInterface $ dataSource ) { return isset ( $ this -> themesVars [ $ dataSource -> getName ( ) ] ) ? $ this -> themesVars [ $ dataSource -> getName ( ) ] : [ ] ; }
Return vars passed to theme. Those vars will be added to block context.

@param DataSourceViewInterface $dataSource
@return array
Return vars passed to theme . Those vars will be added to block context .