One month ago, I decided to empty the backlog of bugs and requests of my plugins.
Before starting this work, I went back in the WordPress Codex, to refresh my knowledge, and get information on the new WordPress 3.x API.

First I read the page Writing a Plugin, that virtually didn’t changed since WordPress 2.3.

After some additional query, I finally found, a document that seems much more interesting: Theme Review including the Guidelines.

This page speaks about themes development, but these recommendations may also be applied with plugins. A similar page for plugins would be welcomed.

The first paragraph of the page catched my attention: the constant WP_DEBUG: when set to TRUE in the file wp-config.php, this variable activates the display of

  • PHP Errors of levels Notice and Warning,
  • Alert messages when the plugin uses a deprecated function, or deprecated arguments.

The activation of DEBUG mode is very useful, to correct bugs that are usually difficult to detect. For example, misuse of arguments in the functions of the WP API.

Therefore, I strongly recommend to plugins and/or themes developers to

  • read the Theme Review,
  • permanently activate the variable WP_DEBUG on their development platform.