Since I wrote the original version of this article long time ago on 04/09/2012 and a lot had happened since then, I no longer have the original article. The following is what I have recovered from Internet Archive Wayback Machine. Note that since the Wayback Machine doesn’t store images, all of the image-referencing content below has been either modified or removed. Please read the version here if you need to see the original article with image placeholders.
In the theme and plugin sections of WordPress admin area, there is an edit button for each theme and plugin in order for you to edit the source code for them. I believe that some of you never touched this button to take advantage of the open source platform provided by WordPress just like me. I think that a lot of plugins to suit my needs, why would I edit somebody’s code?
Until recently, I was testing the Network Latest Posts plugin and noticed that it lacks the date/time display option. I searched for an alternate plugin but no single plugin can support the multisite. Finally I decided to dig through the source code of Network Latest Posts to customize my needs.
Here are the lessons I learned through editing its code:
When I first read through the source code, I noticed a lot of code duplication. I wonder why the plugin developer didn’t place these repeated code into a function for easier access. I think I can improve its code by either move the duplicated code into a function, or convert it into object-oriented structure.
Thanks to the duplicated code in almost all the if…else statements, I used try and test method to modify a bit of code and test the plugin on the front-end. If the changes were not in effect, I reverted back to the original code and moved to the next section of code.
- It’s important to have enough comments
The developer leaves many comments across the source code for this plugin. Thanks those comments, I saved lots of time by skipping the appropriate sections of code during the trying and testing process.
The comments are not just for other people to read through your code. I also learned that it’s easier to navigate through the code for me if I leave comments for the right sections of code.
- Opportunity to learn others’ coding styles
One of the benefits of reading through other people’s source code is to learn their coding styles. If you never write a line of code for a WordPress plugin before, you don’t know the format of the code aside from your own coding style.
Through reading other people’s code, you can beginning to learn different coding styles from different developers. Not for long, you can develop your own coding style by combining the coding styles you learned.
- Knowing the behaviors of the plugin
Another benefit of carefully reading the source code for each of the plugins you installed is to know the behaviors of the plugins. For example, the Network Latest Posts plugin saves the widget options to a database table. This can cause a bunch of useless database records if you installed and uninstalled many plugins.
With this knowledge, I can dig through the database with phpmyadmin to find and delete the records corresponding to the source code. Or I can write a PHP script to delete all of those records based on their code.
If you think a plugin has bad behavior, you can also check its code to see if the code can be modified to correct its behavior, or remove it from WordPress.
Do you know any other benefits for reading other ones’ source code? Please share them in the comments section below.