Update class-wc-taxjar-nexus.php

[MillerMedia]

Describe the problem (reference the issue if applicable) and what the PR accomplishes.

Steps to Reproduce

Receiving this error in a WPEngine hosting environment. We do not know what triggered it but we did see that sometimes $this->nexus can be null in this function in certain instances. Added a simply null check:

Error Details

An error of type E_ERROR was caused in line 24 of the file /nas/content/live/oursite/wp-content/plugins/taxjar-simplified-taxes-for-woocommerce/includes/class-wc-taxjar-nexus.php. Error message: Uncaught TypeError: count(): Argument #1 ($value) must be of type Countable|array, null given in /nas/content/live/oursite/wp-content/plugins/taxjar-simplified-taxes-for-woocommerce/includes/class-wc-taxjar-nexus.php:24 Stack trace:
#0 /nas/content/live/oursite/wp-content/plugins/taxjar-simplified-taxes-for-woocommerce/includes/class-taxjar-settings.php(330): WC_Taxjar_Nexus->get_form_settings_field() #1 /nas/content/live/oursite/wp-content/plugins/taxjar-simplified-taxes-for-woocommerce/includes/class-taxjar-settings.php(208): TaxJar_Settings::get_nexus_settings_display() #2 /nas/content/live/oursite/wp-content/plugins/taxjar-simplified-taxes-for-woocommerce/includes/class-taxjar-settings.php(645): TaxJar_Settings::get_settings() #3 /nas/content/live/oursite/wp-includes/class-wp-hook.php(310): TaxJar_Settings::save('') #4 /nas/content/live/oursite/wp-includes/class-wp-hook.php(334): WP_Hook->apply_filters('', Array) #5 /nas/content/live/oursite/wp-includes/plugin.php(517): WP_Hook->do_action(Array) #6 /nas/content/live/oursite/wp-content/plugins/woocommerce/includes/admin/class-wc-admin-settings.php(77): do_action('woocommerce_set...') #7 /nas/content/live/oursite/wp-content/plugins/woocommerce/includes/admin/class-wc-admin-menus.php(153): WC_Admin_Settings::save() #8 /nas/content/live/oursite/wp-includes/class-wp-hook.php(310): WC_Admin_Menus->save_settings('') #9 /nas/content/live/oursite/wp-includes/class-wp-hook.php(334): WP_Hook->apply_filters(NULL, Array) #10 /nas/content/live/oursite/wp-includes/plugin.php(517): WP_Hook->do_action(Array) #11 /nas/content/live/oursite/wp-settings.php(654): do_action('wp_loaded') #12 /nas/content/live/oursite/wp-config.php(121): require_once('/nas/content/li...') #13 /nas/content/live/oursite/wp-load.php(50): require_once('/nas/content/li...') #14 /nas/content/live/oursite/wp-admin/admin.php(34): require_once('/nas/content/li...') #15 {main}
thrown

Expected Result

No error should be thrown when $this->nexus is null and the admin page with settings is visited.

Click-Test Versions

• [x ] Woo 4.0
• Woo 3.9
• Woo 3.8
• Woo 3.7
• Woo 3.6
• Woo 3.5
• Woo 3.4
• Woo 3.3
• Woo 3.2
• Woo 3.1
• Woo 3.0

Specs Passing

• Woo 4.0
• Woo 3.9
• Woo 3.8
• Woo 3.7
• Woo 3.6
• Woo 3.5
• Woo 3.4
• Woo 3.3
• Woo 3.2
• Woo 3.1
• Woo 3.0

[CLAassistant]

All committers have signed the CLA.

[gabriele-mwd]

Hi, I'm facing quite the same issue but the problem in my case is that $this->nexus is a string, which is not countable, and that is causing a fatal error, too.
I would suggest to replace !is_null( $this->nexus ) with is_countable( $this->nexus ).

I've also noticed that this PR was opened one year ago and it hasn't been merged yet. Is the TaxJar team still active?