Coding Standards

What they are and why they're important

Jonathan Desrosiers - @Desrosj

Me

• Developer
• Work at Boston University
• WordCamp and WordPress Boston Organizer
• Using WordPress 10 years
• Core Contributor
• Multisite & Media contributor
• Leads New Core Contributor meetings in #core

Ninety-Ninety Rule

“The first 90% of the code accounts for the first 90% of the development time. The remaining 10% of the code accounts for the other 90% of the development time.”

- Tim Cargill - Bell Labs

Translation

Estimating development is HARD!

What are Coding Standards?

Guidelines for a specific programming language that dictates:

• style
• practices
• methods

What are Coding Standards?

• File organization
• Indentation
• Comments
• Whitespace
• Naming conventions
• etc.

Examples

Tabs should be used at the beginning of the line for indentation

Examples

Braces shall be used for all code blocks, even when they are not required.

if ( some condition ) {
    action1();
    action2();
} elseif ( another condition ) {
    action3();
    action4();
} else {
    default_action();
}

What are Best Practices?

A set of informal rules that the software development community has learned over time that can help improve the quality of software.

What are Best Practices?

A set of informal rules that the software development community has learned over time that can help improve the quality of software.

Examples

Don't query all posts at once.

$dangerous_post_query = new WP_Query(
    array(
        'post_type'      => 'post',
        'posts_per_page' => -1,
    )
);

Examples

$dangerous_post_query = new WP_Query(
    array(
        'post_type'      => 'post',
        'posts_per_page' => 100,
    )
);

Don't query all posts at once.

Coding Standards

+

Best Practices

=

Increased Software Quality

How do these help?

• Readability
• Compatibility
• Maintainability

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These become easier:

• Code reviews
• Debugging
• Refactoring

These become easier (Business):

• Onboarding new employees
• Outsourcing work

These become easier:

• Open sourcing projects becomes more enjoyable
• Contributing to WordPress becomes less intimidating
• Lower barrier of entry for automated tools

But WordPress does not even follow the coding standards in Core. Why should I?

Tools

Try it out

<?php

function test() {
  $welcome_message_1='Hello there!';
  $welcome_message_2 = 'Welcome!';

if(in_array(date('w'), array(0,6)))
  echo $welcome_message_1;
else
  echo $welcome_message_2;
}
?>

Autofixing

<?php

function test() {
  $welcome_message_1 = 'Hello there!';
  $welcome_message_2 = 'Welcome!';

  if ( in_array( date( 'w' ), array( 0, 6 ) ) ) {
    echo $welcome_message_1;
  } else {
    echo $welcome_message_2;
  }
}

Re-check

Automate

Pre Commit Hook

Continuous Integration

Reporting Services