Writing code, especially in a collaborative environment like open source, requires all participants to follow specific standards. Coding standards help avoid common coding errors, improve the readability of code, and simplify modification. In this workshop, you'll learn about the WordPress Coding Standards, where to find information about them, as well as how to automate the process of formatting your code to meet the coding standards.

1. Jonathan Bossenger
Let’s Code
Learn.WordPress.org
WordPress Coding Standards

2. 2
👋🏽
Welcome!
As you join, please let us know in the chat where
you’re joining us from, and what the weather’s like in
your part of the world…
Hello!
○ My name is Jonathan Bossenger
○ From Cape Town, South Africa
○ Developer educator at Automattic
○ Sponsored to work with the Training Team
○ jonathanbossenger.com

3. Learn.WordPress.org
WordPress Coding
Standards
Jonathan Bossenger

4. Announcements
○ A note on today’s presentation…

5. Announcements
○ Welcome, and thanks to Laura for co-hosting.
○ Please let me know if you can’t see this slide!
○ We are presenting in focus mode, but please feel free to enable your video.
○ You are welcome to ask questions.
○ You are welcome to post questions in the chat, or unmute to ask questions.

6. Announcements
○ The example code from today’s presentation
• https://github.com/jonathanbossenger/wp-learn-coding-
standards/releases/download/1.0.0/wp-learn-coding-standards.1.0.0.zip
• https://www.howtogeek.com/789559/how-to-stop-safari-from-automatically-
unzipping-downloaded-files-on-mac/
○ If I am going too fast, please let me know!
○ We will be posting this session to https://wordpress.tv/ afterwards
○ For more WordPress focused content please visit https://learn.wordpress.org/

7. Learning Outcomes
1. What are Coding Standards?
2. Coding Standards for WordPress
• HTML and CSS Coding Standards
⁃ Validating your HTML and CSS code
• PHP and JavaScript Coding Standards
⁃ Linting your PHP and JavaScript code
3. WordPress Code Examples Starter

8. Let’s code lint.

9. What are Coding Standards?
1. Wikipedia defines them as a set of guidelines for a specific programming language
that recommend programming style, practices, and methods for each aspect of a
program written in that language
2. Coding standards create a baseline for collaboration and review within various
aspects of an open source project and community
3. Coding standards help avoid common coding errors, improve the readability of
code, and simplify modification

10. What are Coding Standards?
1. If you are planning to contribute to WordPress core, you need to familiarize
yourself with these standards, as any code you submit will need to comply with
them.
2. While it is not strictly a requirement, it's also a good idea to follow these standards
when developing plugins and themes
3. It will make your code easier to read and understand, and will make it easier for
other developers to contribute to your code.

11. WordPress Coding Standards
https://developer.wordpress.org/coding-standards/
HTML and CSS Coding Standards:
○ https://developer.wordpress.org/coding-standards/wordpress-coding-standards/html/
○ https://developer.wordpress.org/coding-standards/wordpress-coding-standards/css/
These standards follow the World Wide Web Consortium (or W3C) standards for HTML
and CSS
○ https://www.w3.org/standards/webdesign/htmlcss
○ https://validator.w3.org/
○ https://jigsaw.w3.org/css-validator/

12. WordPress Coding Standards
https://developer.wordpress.org/coding-standards/
PHP and JavaScript Coding Standards:
○ https://developer.wordpress.org/coding-standards/wordpress-coding-standards/php/
○ https://developer.wordpress.org/coding-standards/wordpress-coding-standards/javascript/
These standards were extended from other style guides at the time, but how now been
formalised and are unique to the WordPress project.
Fortunately, there are some linting tools that the project has made available, to check
your code.

13. WordPress Code Linters
PHP
○ https://github.com/squizlabs/PHP_CodeSniffer
○ https://github.com/WordPress/WordPress-Coding-Standards
○ Requires https://getcomposer.org/

14. WordPress Code Linters
PHP - Composer package installation
○ composer require --dev dealerdirect/phpcodesniffer-composer-installer
○ composer require --dev squizlabs/php_codesniffer
○ composer require --dev wp-coding-standards/wpcs

15. WordPress Code Linters
PHP - phpcs.xml configuration
<?xml version="1.0"?>
<ruleset name="WordPress Coding Standards">
<rule ref="WordPress"/>
<arg name="extensions" value="php"/>
<file>.</file>
<!-- Exclude Vendor directory -->
<exclude-pattern>*/vendor/*</exclude-pattern>
<exclude-pattern>*/node_modules/*</exclude-pattern>
</ruleset>

16. WordPress Code Linters
PHP - run command
./vendor/bin/phpcs --standard=phpcs.xml

17. WordPress Code Linters
JavaScript
○ https://developer.wordpress.org/block-editor/reference-guides/packages/packages-
scripts/
○ Requires https://nodejs.org/en

18. WordPress Code Linters
JavaScript - npm package installation
○ npm init
○ npm install @wordpress/scripts --save-dev

19. WordPress Code Linters
JavaScript - package.json scripts
"scripts": {
"build": "wp-scripts build",
"check-engines": "wp-scripts check-engines",
"check-licenses": "wp-scripts check-licenses",
"format": "wp-scripts format",
"lint:css": "wp-scripts lint-style",
"lint:js": "wp-scripts lint-js",
"lint:md:docs": "wp-scripts lint-md-docs",
"lint:pkg-json": "wp-scripts lint-pkg-json",
"packages-update": "wp-scripts packages-update",
"plugin-zip": "wp-scripts plugin-zip",
"start": "wp-scripts start",
"test:e2e": "wp-scripts test-e2e",
"test:unit": "wp-scripts test-unit-js"
}

20. WordPress Code Linters
JavaScript - run command
npm run lint:js

21. WordPress Code Examples Starter
https://github.com/ryanwelcher/wordpress-project-template

22. Resources
○ https://github.com/jonathanbossenger/wp-learn-coding-standards/releases/download/1.0.0/wp-
learn-coding-standards.1.0.0.zip
○ https://en.wikipedia.org/wiki/Coding_conventions
○ https://developer.wordpress.org/coding-standards/
○ https://developer.wordpress.org/coding-standards/wordpress-coding-standards/html/
○ https://developer.wordpress.org/coding-standards/wordpress-coding-standards/css/
○ https://www.w3.org/standards/webdesign/htmlcss
○ https://validator.w3.org/
○ https://jigsaw.w3.org/css-validator/

23. Resources
○ https://github.com/squizlabs/PHP_CodeSniffer
○ https://github.com/WordPress/WordPress-Coding-Standards
○ https://getcomposer.org/
○ https://developer.wordpress.org/block-editor/reference-guides/packages/packages-scripts/
○ https://nodejs.org/en/download