Ivelina Dimova - The Magic of Advanced Debugging

As lead of the Ongoing Client Support at CrowdFavorite I’ve worked with lots of legacy code on different projects. This session covers some of the lessons we’ve learned in the process and tips how to deal with the most common issues faster and more effective. It also shows how the legacy code can be actually fun.

Transcript

1. The Magic of
   Advanced Debugging
   

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3. Work Days
   

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5. Once upon a time
   

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8. Where to start
   

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9. Don’t ever debug on
   production
   

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10. Set debug constants
    

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13. Fatal error: Cannot use object of type stdClass as array in
    /Users/ivdimova/Sites/project.dev/wordpress/wp-content/plugin
    s/custom-social-feed/includes/init.php on line 645, referer:
    http://project.dev/
    

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14. Invalid argument supplied for foreach() in
    /Users/ivdimova/Sites/project.dev/wp-includes/plugin.php on
    line 523
    

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15. Plugin conflicts?!
    

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16. Grep all the things
    grep all the things
    

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17. var_dump();
    error_log();
    error_log( print_r( $object, 1 ) );
    

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18. Query Monitor
    

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20. Xdebug
    

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26. Permissions, permissions
    

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27. Version Control
    

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28. git log
    

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29. git blame
    

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31. Identify filters and hooks
    

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32. add_action( 'plugins_loaded', 'prefix_remove_action', 10 );
    function prefix_remove_action() {
    $invoice = new WC_Gateway_Sprout_Invoices();
    $result = remove_action( 'woocommerce_thankyou_sprout_invoices', array(
    $invoice, 'thankyou_page' ), 20 );
    }
    

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36. Leave legacy for others
    

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38. Contact:
    iv.dimova@gmail.com
    @iv_wp
    https://www.linkedin.com/in/ivdimova
    

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