390 lines
12 KiB
PHP
390 lines
12 KiB
PHP
<?php
|
|
/**
|
|
* GitHub-Flavoured Markdown. Inspired by Evan's plugin, but modified.
|
|
*
|
|
* @author Evan Solomon
|
|
* @author Matt Wiebe <wiebe@automattic.com>
|
|
* @link https://github.com/evansolomon/wp-github-flavored-markdown-comments
|
|
*
|
|
* Add a few extras from GitHub's Markdown implementation. Must be used in a WordPress environment.
|
|
*/
|
|
|
|
class WPCom_GHF_Markdown_Parser extends MarkdownExtra_Parser {
|
|
|
|
/**
|
|
* Hooray somewhat arbitrary numbers that are fearful of 1.0.x.
|
|
*/
|
|
const WPCOM_GHF_MARDOWN_VERSION = '0.9.0';
|
|
|
|
/**
|
|
* Use a [code] shortcode when encountering a fenced code block
|
|
* @var boolean
|
|
*/
|
|
public $use_code_shortcode = true;
|
|
|
|
/**
|
|
* Preserve shortcodes, untouched by Markdown.
|
|
* This requires use within a WordPress installation.
|
|
* @var boolean
|
|
*/
|
|
public $preserve_shortcodes = true;
|
|
|
|
/**
|
|
* Preserve the legacy $latex your-latex-code-here$ style
|
|
* LaTeX markup
|
|
*/
|
|
public $preserve_latex = true;
|
|
|
|
/**
|
|
* Preserve single-line <code> blocks.
|
|
* @var boolean
|
|
*/
|
|
public $preserve_inline_code_blocks = true;
|
|
|
|
/**
|
|
* Strip paragraphs from the output. This is the right default for WordPress,
|
|
* which generally wants to create its own paragraphs with `wpautop`
|
|
* @var boolean
|
|
*/
|
|
public $strip_paras = true;
|
|
|
|
// Will run through sprintf - you can supply your own syntax if you want
|
|
public $shortcode_start = '[code lang=%s]';
|
|
public $shortcode_end = '[/code]';
|
|
|
|
// Stores shortcodes we remove and then replace
|
|
protected $preserve_text_hash = array();
|
|
|
|
/**
|
|
* Set environment defaults based on presence of key functions/classes.
|
|
*/
|
|
public function __construct() {
|
|
$this->use_code_shortcode = class_exists( 'SyntaxHighlighter' );
|
|
$this->preserve_shortcodes = function_exists( 'get_shortcode_regex' );
|
|
$this->preserve_latex = function_exists( 'latex_markup' );
|
|
$this->strip_paras = function_exists( 'wpautop' );
|
|
|
|
parent::__construct();
|
|
}
|
|
|
|
/**
|
|
* Overload to specify heading styles only if the hash has space(s) after it. This is actually in keeping with
|
|
* the documentation and eases the semantic overload of the hash character.
|
|
* #Will Not Produce a Heading 1
|
|
* # This Will Produce a Heading 1
|
|
*
|
|
* @param string $text Markdown text
|
|
* @return string HTML-transformed text
|
|
*/
|
|
public function transform( $text ) {
|
|
// Preserve anything inside a single-line <code> element
|
|
if ( $this->preserve_inline_code_blocks ) {
|
|
$text = $this->single_line_code_preserve( $text );
|
|
}
|
|
// Remove all shortcodes so their interiors are left intact
|
|
if ( $this->preserve_shortcodes ) {
|
|
$text = $this->shortcode_preserve( $text );
|
|
}
|
|
// Remove legacy LaTeX so it's left intact
|
|
if ( $this->preserve_latex ) {
|
|
$text = $this->latex_preserve( $text );
|
|
}
|
|
|
|
// escape line-beginning # chars that do not have a space after them.
|
|
$text = preg_replace_callback( '|^#{1,6}( )?|um', array( $this, '_doEscapeForHashWithoutSpacing' ), $text );
|
|
|
|
/**
|
|
* Allow third-party plugins to define custom patterns that won't be processed by Markdown.
|
|
*
|
|
* @module markdown
|
|
*
|
|
* @since 3.9.2
|
|
*
|
|
* @param array $custom_patterns Array of custom patterns to be ignored by Markdown.
|
|
*/
|
|
$custom_patterns = apply_filters( 'jetpack_markdown_preserve_pattern', array() );
|
|
if ( is_array( $custom_patterns ) && ! empty( $custom_patterns ) ) {
|
|
foreach ( $custom_patterns as $pattern ) {
|
|
$text = preg_replace_callback( $pattern, array( $this, '_doRemoveText'), $text );
|
|
}
|
|
}
|
|
|
|
// run through core Markdown
|
|
$text = parent::transform( $text );
|
|
|
|
// Occasionally Markdown Extra chokes on a para structure, producing odd paragraphs.
|
|
$text = str_replace( "<p><</p>\n\n<p>p>", '<p>', $text );
|
|
|
|
// put start-of-line # chars back in place
|
|
$text = $this->restore_leading_hash( $text );
|
|
|
|
// Strip paras if set
|
|
if ( $this->strip_paras ) {
|
|
$text = $this->unp( $text );
|
|
}
|
|
|
|
// Restore preserved things like shortcodes/LaTeX
|
|
$text = $this->do_restore( $text );
|
|
|
|
return $text;
|
|
}
|
|
|
|
/**
|
|
* Prevents blocks like <code>__this__</code> from turning into <code><strong>this</strong></code>
|
|
* @param string $text Text that may need preserving
|
|
* @return string Text that was preserved if needed
|
|
*/
|
|
public function single_line_code_preserve( $text ) {
|
|
return preg_replace_callback( '|<code\b[^>]*>(.*?)</code>|', array( $this, 'do_single_line_code_preserve' ), $text );
|
|
}
|
|
|
|
/**
|
|
* Regex callback for inline code presevation
|
|
* @param array $matches Regex matches
|
|
* @return string Hashed content for later restoration
|
|
*/
|
|
public function do_single_line_code_preserve( $matches ) {
|
|
return '<code>' . $this->hash_block( $matches[1] ) . '</code>';
|
|
}
|
|
|
|
/**
|
|
* Preserve code block contents by HTML encoding them. Useful before getting to KSES stripping.
|
|
* @param string $text Markdown/HTML content
|
|
* @return string Markdown/HTML content with escaped code blocks
|
|
*/
|
|
public function codeblock_preserve( $text ) {
|
|
return preg_replace_callback( "/^([`~]{3})([^`\n]+)?\n([^`~]+)(\\1)/m", array( $this, 'do_codeblock_preserve' ), $text );
|
|
}
|
|
|
|
/**
|
|
* Regex callback for code block preservation.
|
|
* @param array $matches Regex matches
|
|
* @return string Codeblock with escaped interior
|
|
*/
|
|
public function do_codeblock_preserve( $matches ) {
|
|
$block = stripslashes( $matches[3] );
|
|
$block = esc_html( $block );
|
|
$block = str_replace( '\\', '\\\\', $block );
|
|
$open = $matches[1] . $matches[2] . "\n";
|
|
return $open . $block . $matches[4];
|
|
}
|
|
|
|
/**
|
|
* Restore previously preserved (i.e. escaped) code block contents.
|
|
* @param string $text Markdown/HTML content with escaped code blocks
|
|
* @return string Markdown/HTML content
|
|
*/
|
|
public function codeblock_restore( $text ) {
|
|
return preg_replace_callback( "/^([`~]{3})([^`\n]+)?\n([^`~]+)(\\1)/m", array( $this, 'do_codeblock_restore' ), $text );
|
|
}
|
|
|
|
/**
|
|
* Regex callback for code block restoration (unescaping).
|
|
* @param array $matches Regex matches
|
|
* @return string Codeblock with unescaped interior
|
|
*/
|
|
public function do_codeblock_restore( $matches ) {
|
|
$block = html_entity_decode( $matches[3], ENT_QUOTES );
|
|
$open = $matches[1] . $matches[2] . "\n";
|
|
return $open . $block . $matches[4];
|
|
}
|
|
|
|
/**
|
|
* Called to preserve legacy LaTeX like $latex some-latex-text $
|
|
* @param string $text Text in which to preserve LaTeX
|
|
* @return string Text with LaTeX replaced by a hash that will be restored later
|
|
*/
|
|
protected function latex_preserve( $text ) {
|
|
// regex from latex_remove()
|
|
$regex = '%
|
|
\$latex(?:=\s*|\s+)
|
|
((?:
|
|
[^$]+ # Not a dollar
|
|
|
|
|
(?<=(?<!\\\\)\\\\)\$ # Dollar preceded by exactly one slash
|
|
)+)
|
|
(?<!\\\\)\$ # Dollar preceded by zero slashes
|
|
%ix';
|
|
$text = preg_replace_callback( $regex, array( $this, '_doRemoveText'), $text );
|
|
return $text;
|
|
}
|
|
|
|
/**
|
|
* Called to preserve WP shortcodes from being formatted by Markdown in any way.
|
|
* @param string $text Text in which to preserve shortcodes
|
|
* @return string Text with shortcodes replaced by a hash that will be restored later
|
|
*/
|
|
protected function shortcode_preserve( $text ) {
|
|
$text = preg_replace_callback( $this->get_shortcode_regex(), array( $this, '_doRemoveText' ), $text );
|
|
return $text;
|
|
}
|
|
|
|
/**
|
|
* Restores any text preserved by $this->hash_block()
|
|
* @param string $text Text that may have hashed preservation placeholders
|
|
* @return string Text with hashed preseravtion placeholders replaced by original text
|
|
*/
|
|
protected function do_restore( $text ) {
|
|
foreach( $this->preserve_text_hash as $hash => $value ) {
|
|
$placeholder = $this->hash_maker( $hash );
|
|
$text = str_replace( $placeholder, $value, $text );
|
|
}
|
|
// reset the hash
|
|
$this->preserve_text_hash = array();
|
|
return $text;
|
|
}
|
|
|
|
/**
|
|
* Regex callback for text preservation
|
|
* @param array $m Regex $matches array
|
|
* @return string A placeholder that will later be replaced by the original text
|
|
*/
|
|
protected function _doRemoveText( $m ) {
|
|
return $this->hash_block( $m[0] );
|
|
}
|
|
|
|
/**
|
|
* Call this to store a text block for later restoration.
|
|
* @param string $text Text to preserve for later
|
|
* @return string Placeholder that will be swapped out later for the original text
|
|
*/
|
|
protected function hash_block( $text ) {
|
|
$hash = md5( $text );
|
|
$this->preserve_text_hash[ $hash ] = $text;
|
|
$placeholder = $this->hash_maker( $hash );
|
|
return $placeholder;
|
|
}
|
|
|
|
/**
|
|
* Less glamorous than the Keymaker
|
|
* @param string $hash An md5 hash
|
|
* @return string A placeholder hash
|
|
*/
|
|
protected function hash_maker( $hash ) {
|
|
return 'MARKDOWN_HASH' . $hash . 'MARKDOWN_HASH';
|
|
}
|
|
|
|
/**
|
|
* Remove bare <p> elements. <p>s with attributes will be preserved.
|
|
* @param string $text HTML content
|
|
* @return string <p>-less content
|
|
*/
|
|
public function unp( $text ) {
|
|
return preg_replace( "#<p>(.*?)</p>(\n|$)#ums", '$1$2', $text );
|
|
}
|
|
|
|
/**
|
|
* A regex of all shortcodes currently registered by the current
|
|
* WordPress installation
|
|
* @uses get_shortcode_regex()
|
|
* @return string A regex for grabbing shortcodes.
|
|
*/
|
|
protected function get_shortcode_regex() {
|
|
$pattern = get_shortcode_regex();
|
|
|
|
// don't match markdown link anchors that could be mistaken for shortcodes.
|
|
$pattern .= '(?!\()';
|
|
|
|
return "/$pattern/s";
|
|
}
|
|
|
|
/**
|
|
* Since we escape unspaced #Headings, put things back later.
|
|
* @param string $text text with a leading escaped hash
|
|
* @return string text with leading hashes unescaped
|
|
*/
|
|
protected function restore_leading_hash( $text ) {
|
|
return preg_replace( "/^(<p>)?(#|\\\\#)/um", "$1#", $text );
|
|
}
|
|
|
|
/**
|
|
* Overload to support ```-fenced code blocks for pre-Markdown Extra 1.2.8
|
|
* https://help.github.com/articles/github-flavored-markdown#fenced-code-blocks
|
|
*/
|
|
public function doFencedCodeBlocks( $text ) {
|
|
// If we're at least at 1.2.8, native fenced code blocks are in.
|
|
// Below is just copied from it in case we somehow got loaded on
|
|
// top of someone else's Markdown Extra
|
|
if ( version_compare( MARKDOWNEXTRA_VERSION, '1.2.8', '>=' ) )
|
|
return parent::doFencedCodeBlocks( $text );
|
|
|
|
#
|
|
# Adding the fenced code block syntax to regular Markdown:
|
|
#
|
|
# ~~~
|
|
# Code block
|
|
# ~~~
|
|
#
|
|
$less_than_tab = $this->tab_width;
|
|
|
|
$text = preg_replace_callback('{
|
|
(?:\n|\A)
|
|
# 1: Opening marker
|
|
(
|
|
(?:~{3,}|`{3,}) # 3 or more tildes/backticks.
|
|
)
|
|
[ ]*
|
|
(?:
|
|
\.?([-_:a-zA-Z0-9]+) # 2: standalone class name
|
|
|
|
|
'.$this->id_class_attr_catch_re.' # 3: Extra attributes
|
|
)?
|
|
[ ]* \n # Whitespace and newline following marker.
|
|
|
|
# 4: Content
|
|
(
|
|
(?>
|
|
(?!\1 [ ]* \n) # Not a closing marker.
|
|
.*\n+
|
|
)+
|
|
)
|
|
|
|
# Closing marker.
|
|
\1 [ ]* (?= \n )
|
|
}xm',
|
|
array($this, '_doFencedCodeBlocks_callback'), $text);
|
|
|
|
return $text;
|
|
}
|
|
|
|
/**
|
|
* Callback for pre-processing start of line hashes to slyly escape headings that don't
|
|
* have a leading space
|
|
* @param array $m preg_match matches
|
|
* @return string possibly escaped start of line hash
|
|
*/
|
|
public function _doEscapeForHashWithoutSpacing( $m ) {
|
|
if ( ! isset( $m[1] ) )
|
|
$m[0] = '\\' . $m[0];
|
|
return $m[0];
|
|
}
|
|
|
|
/**
|
|
* Overload to support Viper's [code] shortcode. Because awesome.
|
|
*/
|
|
public function _doFencedCodeBlocks_callback( $matches ) {
|
|
// in case we have some escaped leading hashes right at the start of the block
|
|
$matches[4] = $this->restore_leading_hash( $matches[4] );
|
|
// just MarkdownExtra_Parser if we're not going ultra-deluxe
|
|
if ( ! $this->use_code_shortcode ) {
|
|
return parent::_doFencedCodeBlocks_callback( $matches );
|
|
}
|
|
|
|
// default to a "text" class if one wasn't passed. Helps with encoding issues later.
|
|
if ( empty( $matches[2] ) ) {
|
|
$matches[2] = 'text';
|
|
}
|
|
|
|
$classname =& $matches[2];
|
|
$codeblock = preg_replace_callback('/^\n+/', array( $this, '_doFencedCodeBlocks_newlines' ), $matches[4] );
|
|
|
|
if ( $classname{0} == '.' )
|
|
$classname = substr( $classname, 1 );
|
|
|
|
$codeblock = esc_html( $codeblock );
|
|
$codeblock = sprintf( $this->shortcode_start, $classname ) . "\n{$codeblock}" . $this->shortcode_end;
|
|
return "\n\n" . $this->hashBlock( $codeblock ). "\n\n";
|
|
}
|
|
|
|
}
|