Fix ‘Invalid argument supplied for foreach()’ error

Specifically, this code applies to  gravity-forms-custom-post-types/gfcptaddonbase.php, but it could apply to other instances of the error.

Original code:

foreach( $form_or_field['fields'] as $field ) {
    if( $this->has_tax_enhanced_ui( $field ) ) {
    return true;
    }
}

Fixed (added ‘if not empty’ conditional):

if( !empty($form_or_field['fields']) ) {
    foreach( $form_or_field['fields'] as $field ) {
        if( $this->has_tax_enhanced_ui( $field ) ) {
        return true;
        }
    }
}

Reference Links

https://stackoverflow.com/questions/18951168/invalid-argument-supplied-for-foreach-in-codeigniter