Real Refactoring Example

Even though I use and like Genesis doesn’t mean there aren’t areas where it doesn’t fully comply with clean, quality coding techniques. In the last episode, I showed you the code for processing the post image. Did you notice that the code within the function genesis_do_post_image() will not run (none of it) if the conditional expression is not true? Ah, this is a perfect example of when to return early.

Return early pattern: when you are done processing and nothing else in the function/method is going to be processed, then so bail out and return early.

Why? Why would you do this? Because it unwraps your code, expresses your intent, and makes it easier to read. Remember that readable is a HUGE thing in programming. It’s the difference between maintainable, reusable code and costly, hard to maintain code. When you see a return, you know you are done and that’s it. This is the point of using a return early pattern.

In this episode, I’m going to walk you through the code, talk about the reasons why and how to spot it, and show you how to refactor it. And guess, what? There are two (2) return early pattern opportunities in this one function. It’s an excellent opportunity for me to teach you about the software principles of clean, quality coding.

Real code example that needs to be refactored

	function genesis_do_post_image() {
	/**
	* Return Early Pattern opportunity
	* ================================
	* Notice that the code wrapped in this conditional block only executes IF the
	* conditional expression is true. Hum, that means if the conditional expression
	* is false, then the function is done and nothing else is going to happen.
	*/
	if ( ! is_singular() && genesis_get_option( 'content_archive_thumbnail' ) ) {
	$img = genesis_get_image( array(
	'format' => 'html',
	'size' => genesis_get_option( 'image_size' ),
	'context' => 'archive',
	'attr' => genesis_parse_attr( 'entry-image', array ( 'alt' => get_the_title() ) ),
	) );
	/**
	* Return Early Pattern opportunity
	* ================================
	* Here's another one. If no image HTML is returned, then the function is done and nothing
	* else is going to happen. That means the code within the IF block will not execute.
	*/
	if ( ! empty( $img ) ) {
	genesis_markup( array(
	'html5' => '<a %s>',
	'xhtml' => '<a href="' . get_permalink() . '" class="entry-image-link" aria-hidden="true">',
	'context' => 'entry-image-link'
	));
	echo $img . '</a>';
	}
	}
	}

view raw

post.php

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Same code after refactoring

	function genesis_do_post_image() {
	if ( is_singular() || ! genesis_get_option( 'content_archive_thumbnail' ) ) {
	return;
	}
	$img = genesis_get_image( array(
	'format' => 'html',
	'size' => genesis_get_option( 'image_size' ),
	'context' => 'archive',
	'attr' => genesis_parse_attr( 'entry-image', array ( 'alt' => get_the_title() ) ),
	) );
	if ( empty( $img ) ) {
	return;
	}
	genesis_markup( array(
	'html5' => '<a %s>',
	'xhtml' => '<a href="' . get_permalink() . '" class="entry-image-link" aria-hidden="true">',
	'context' => 'entry-image-link'
	));
	echo $img . '</a>';
	}

view raw

post.php

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Jeffrey Way at Laracast has an excellent video on refactoring multiple levels in your code: Simple Rules for Simpler Code: One Level of Indentation. Check it out.