wpautop()WP 0.71

Replaces double line-breaks with paragraph elements.

A group of regex replaces used to identify text formatted with newlines and replace double line breaks with HTML paragraph tags. The remaining line breaks after conversion become <br /> tags, unless $br is set to '0' or 'false'.

1 time — 0.000803 sec (slow) | 50000 times — 3.07 sec (fast) | PHP 7.2.16, WP 5.2.1

No Hooks.

Return

String. Text which has been converted into correct paragraph tags.

Usage

wpautop( $text, $br );
$text(string) (required)
The text which has to be formatted.
$br(true|false)
If set, this will convert all remaining line breaks after paragraphing. Line breaks within <script>, <style>, and <svg> tags are not affected.
Default: true

Examples

0

#1 Add paragraphs to the text:

$some_text = <<<TXT
Some great text
having line breaks

<div>and the text inside the block element div</div>

and also, double line breaks (paragraphs).
TXT;

echo wpautop( $some_text );

The result is:

<p>Some great text<br />
having line breaks</p>
<div>and the text inside the block element div</div>
<p>and also, double line breaks (paragraphs);</p>
0

#2 If you pass an empty string

var_dump( wpautop( '' ) ); // string(0) ""
0

#3 Disable wpautop()

If you have problems with wpautop adding paragraphs where you don’t want them, you can disable it in the content of your posts by adding the following to your child theme’s functions.php file:

remove_filter( 'the_content', 'wpautop' );
remove_filter( 'the_excerpt', 'wpautop' );

Changelog

Since 0.71 Introduced.

wpautop() code WP 6.1.1

function wpautop( $text, $br = true ) {
	$pre_tags = array();

	if ( trim( $text ) === '' ) {
		return '';
	}

	// Just to make things a little easier, pad the end.
	$text = $text . "\n";

	/*
	 * Pre tags shouldn't be touched by autop.
	 * Replace pre tags with placeholders and bring them back after autop.
	 */
	if ( strpos( $text, '<pre' ) !== false ) {
		$text_parts = explode( '</pre>', $text );
		$last_part  = array_pop( $text_parts );
		$text       = '';
		$i          = 0;

		foreach ( $text_parts as $text_part ) {
			$start = strpos( $text_part, '<pre' );

			// Malformed HTML?
			if ( false === $start ) {
				$text .= $text_part;
				continue;
			}

			$name              = "<pre wp-pre-tag-$i></pre>";
			$pre_tags[ $name ] = substr( $text_part, $start ) . '</pre>';

			$text .= substr( $text_part, 0, $start ) . $name;
			$i++;
		}

		$text .= $last_part;
	}
	// Change multiple <br>'s into two line breaks, which will turn into paragraphs.
	$text = preg_replace( '|<br\s*/?>\s*<br\s*/?>|', "\n\n", $text );

	$allblocks = '(?:table|thead|tfoot|caption|col|colgroup|tbody|tr|td|th|div|dl|dd|dt|ul|ol|li|pre|form|map|area|blockquote|address|math|style|p|h[1-6]|hr|fieldset|legend|section|article|aside|hgroup|header|footer|nav|figure|figcaption|details|menu|summary)';

	// Add a double line break above block-level opening tags.
	$text = preg_replace( '!(<' . $allblocks . '[\s/>])!', "\n\n$1", $text );

	// Add a double line break below block-level closing tags.
	$text = preg_replace( '!(</' . $allblocks . '>)!', "$1\n\n", $text );

	// Add a double line break after hr tags, which are self closing.
	$text = preg_replace( '!(<hr\s*?/?>)!', "$1\n\n", $text );

	// Standardize newline characters to "\n".
	$text = str_replace( array( "\r\n", "\r" ), "\n", $text );

	// Find newlines in all elements and add placeholders.
	$text = wp_replace_in_html_tags( $text, array( "\n" => ' <!-- wpnl --> ' ) );

	// Collapse line breaks before and after <option> elements so they don't get autop'd.
	if ( strpos( $text, '<option' ) !== false ) {
		$text = preg_replace( '|\s*<option|', '<option', $text );
		$text = preg_replace( '|</option>\s*|', '</option>', $text );
	}

	/*
	 * Collapse line breaks inside <object> elements, before <param> and <embed> elements
	 * so they don't get autop'd.
	 */
	if ( strpos( $text, '</object>' ) !== false ) {
		$text = preg_replace( '|(<object[^>]*>)\s*|', '$1', $text );
		$text = preg_replace( '|\s*</object>|', '</object>', $text );
		$text = preg_replace( '%\s*(</?(?:param|embed)[^>]*>)\s*%', '$1', $text );
	}

	/*
	 * Collapse line breaks inside <audio> and <video> elements,
	 * before and after <source> and <track> elements.
	 */
	if ( strpos( $text, '<source' ) !== false || strpos( $text, '<track' ) !== false ) {
		$text = preg_replace( '%([<\[](?:audio|video)[^>\]]*[>\]])\s*%', '$1', $text );
		$text = preg_replace( '%\s*([<\[]/(?:audio|video)[>\]])%', '$1', $text );
		$text = preg_replace( '%\s*(<(?:source|track)[^>]*>)\s*%', '$1', $text );
	}

	// Collapse line breaks before and after <figcaption> elements.
	if ( strpos( $text, '<figcaption' ) !== false ) {
		$text = preg_replace( '|\s*(<figcaption[^>]*>)|', '$1', $text );
		$text = preg_replace( '|</figcaption>\s*|', '</figcaption>', $text );
	}

	// Remove more than two contiguous line breaks.
	$text = preg_replace( "/\n\n+/", "\n\n", $text );

	// Split up the contents into an array of strings, separated by double line breaks.
	$paragraphs = preg_split( '/\n\s*\n/', $text, -1, PREG_SPLIT_NO_EMPTY );

	// Reset $text prior to rebuilding.
	$text = '';

	// Rebuild the content as a string, wrapping every bit with a <p>.
	foreach ( $paragraphs as $paragraph ) {
		$text .= '<p>' . trim( $paragraph, "\n" ) . "</p>\n";
	}

	// Under certain strange conditions it could create a P of entirely whitespace.
	$text = preg_replace( '|<p>\s*</p>|', '', $text );

	// Add a closing <p> inside <div>, <address>, or <form> tag if missing.
	$text = preg_replace( '!<p>([^<]+)</(div|address|form)>!', '<p>$1</p></$2>', $text );

	// If an opening or closing block element tag is wrapped in a <p>, unwrap it.
	$text = preg_replace( '!<p>\s*(</?' . $allblocks . '[^>]*>)\s*</p>!', '$1', $text );

	// In some cases <li> may get wrapped in <p>, fix them.
	$text = preg_replace( '|<p>(<li.+?)</p>|', '$1', $text );

	// If a <blockquote> is wrapped with a <p>, move it inside the <blockquote>.
	$text = preg_replace( '|<p><blockquote([^>]*)>|i', '<blockquote$1><p>', $text );
	$text = str_replace( '</blockquote></p>', '</p></blockquote>', $text );

	// If an opening or closing block element tag is preceded by an opening <p> tag, remove it.
	$text = preg_replace( '!<p>\s*(</?' . $allblocks . '[^>]*>)!', '$1', $text );

	// If an opening or closing block element tag is followed by a closing <p> tag, remove it.
	$text = preg_replace( '!(</?' . $allblocks . '[^>]*>)\s*</p>!', '$1', $text );

	// Optionally insert line breaks.
	if ( $br ) {
		// Replace newlines that shouldn't be touched with a placeholder.
		$text = preg_replace_callback( '/<(script|style|svg).*?<\/\\1>/s', '_autop_newline_preservation_helper', $text );

		// Normalize <br>
		$text = str_replace( array( '<br>', '<br/>' ), '<br />', $text );

		// Replace any new line characters that aren't preceded by a <br /> with a <br />.
		$text = preg_replace( '|(?<!<br />)\s*\n|', "<br />\n", $text );

		// Replace newline placeholders with newlines.
		$text = str_replace( '<WPPreserveNewline />', "\n", $text );
	}

	// If a <br /> tag is after an opening or closing block tag, remove it.
	$text = preg_replace( '!(</?' . $allblocks . '[^>]*>)\s*<br />!', '$1', $text );

	// If a <br /> tag is before a subset of opening or closing block tags, remove it.
	$text = preg_replace( '!<br />(\s*</?(?:p|li|div|dl|dd|dt|th|pre|td|ul|ol)[^>]*>)!', '$1', $text );
	$text = preg_replace( "|\n</p>$|", '</p>', $text );

	// Replace placeholder <pre> tags with their original content.
	if ( ! empty( $pre_tags ) ) {
		$text = str_replace( array_keys( $pre_tags ), array_values( $pre_tags ), $text );
	}

	// Restore newlines in all elements.
	if ( false !== strpos( $text, '<!-- wpnl -->' ) ) {
		$text = str_replace( array( ' <!-- wpnl --> ', '<!-- wpnl -->' ), "\n", $text );
	}

	return $text;
}