No Debug Code

July 16, 2015 ยท View on GitHub

Debug code is be of several flavor :

  • var_dump and print_r
  • debug_print_backtrace and debug_backtrace (the latter one has to be printed)
  • $php_errormsg variable (also when printed)
  • ini_set with display_errors and html_errors directives
  • print or echo with information (i.e. echo 'DEBUG';. That includes HTML comments or $debug messages.
  • Helper functions or classes, such as Kint, php-ref, dump_r, Krumo, dBug.
<?php

if (!is_object($dbconnexion)) {
	debug($dbconnexion);
	die();
}
?>

The most suited tool for debugging is a PHP debugger, that will run the code and give a full view of the situation, call stack and variable values. PHP debuggers also allow step by step execution. They are usually integrated with the IDE.

It is recommended to remove all mention to those tools in production code, so as to avoid situations where they are really used (and are in production).

Rule Details

The following patterns are considered warnings:

<?php

print 'debug';

require '/kint/Kint.class.php';
Kint::dump( $_SERVER );

?>

Further Readings