Christina Reichel

i think this can be generalised as a false positive whenever the check for null is done indirectly (so not something along the lines of `$foo !== null` or `empty($foo)`)....

IMO that problem is solved by just having a doc comment saying "This is a method stub that can be overridden for writers that support this functionality" or something along...

I also added a `BaseStringHelper::contains()` function as php7 does not have `str_contains`. This will become redundant once the minimum supported php version is raised to php8.0 or higher.

> This method is already redundant for ~70% of framework users if that number is true, that'd mean not including the polyfill would be a breaking change for 30% of...

so in other words, you'd rather have it as a construct like ```php if (function_exists('str_contains') ? str_contains([...]) : (mb_strpos([...]) !== -1)) ``` ? I originally considered doing that, but figured...

alright, done :)

if this can't be merged for some reason, another solution that doesn't involve code changes would be to update the composer.json to read `"phpoffice/phpspreadsheet": "^1.0"` rather than `"phpoffice/phpspreadsheet": ">=1.0"`, forcing...

@gshap1995 a 2.0.0 version with breaking changes (including this) is already planned, but might still take a bit: https://github.com/kartik-v/yii2-export/pull/381#issuecomment-2608692933