Running data recurring… Warning: count(): Parameter must be an array or an object that implements Countable in lib/internal/Magento/Framework/View/Design/Theme/ThemeList.php on line 237
I have encountered this issue in a bin/magento setup:upgrade response after upgrading PHP to 7.2.
The «Changelog» section of the PHP count() function specification says:
| Version | Description |
|---|---|
| 7.2.0 |
count() will now yield a warning on invalid countable types passed to the array_or_countable parameter. |
http://php.net/manual/en/function.count.php#refsect1-function.count-changelog
«PHP RFC: Counting of non-countable objects» says:
Calling count() on a scalar or object that doesn’t implement the
Countableinterface returns1.
There are no known use cases for this, and it can easily hide bugs <…>.
<…>
This RFC proposes adding a warning when calling count() with a parameter that is a scalar, null, or an object that doesn’t implementCountable.
You need to patch the Magento\Framework\View\Design\Theme\ThemeList::_prepareConfigurationData() method.
Replace the line:
with the following one:
if ($parentPathPieces && count($parentPathPieces) == 1) {
See also
count(): Parameter must be an array or an object that implements Countable in Magento/Theme/Block/Html/Topmenu.php on line 241».count(): Parameter must be an array or an object that implements Countable in Magento/Backend/Block/Menu.php on line 390».count(): Parameter must be an array or an object that implements Countable in Magento/Wishlist/Observer/AddToCart.php on line 79».It is fixed at 2018-01-25 in the Magento 2.3 development branch:
Thank it’s working 
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