lib/IniModifierArray.php
public function getSectionList()
    {
        $list = [];
        foreach ($this->modifiers as $mod) {
            $list = array_merge($list, $mod->getSectionList());
        }
        return array_unique($list);
    }
public function getSectionList()
    {
        $list = [];
        foreach ($this->modifiers as $mod) {
            $list = array_merge($list, $mod->getSectionList());
        }
        return array_unique($list);
    }
return the list of section names.

@return array