Finalization of fenced code block improvements by Mario Konrad:

- Moving `code_block_content_func` configuration variable to regular Markdown parser, now using it to convert the content of indented code blocks to HTML too.
- Fix for code block class name and special attribute blocks together.
- Updated the fenced code block syntax in the HTML block parser (so it correctly skips those code blocks).
- Updated Readme.md to explain the changes.

Michelf/Markdown.php

@@ -64,6 +64,9 @@ class Markdown implements MarkdownInterface {
 
 	# Optional header id="" generation callback function.
 	public $header_id_func = null;
+	
+	# Optional function for converting code block content to HTML
+	public $code_block_content_func = null;
 
 	# Class attribute to toggle "enhanced ordered list" behaviour
 	# setting this to true will allow ordered lists to start from the index
@@ -1024,7 +1027,11 @@ class Markdown implements MarkdownInterface {
 		$codeblock = $matches[1];
 
 		$codeblock = $this->outdent($codeblock);
-		$codeblock = htmlspecialchars($codeblock, ENT_NOQUOTES);
+		if ($this->code_block_content_func) {
+			$codeblock = call_user_func($this->code_block_content_func, $codeblock, "");
+		} else {
+			$codeblock = htmlspecialchars($codeblock, ENT_NOQUOTES);
+		}
 
 		# trim leading newlines and trailing newlines
 		$codeblock = preg_replace('/\A\n+|\n+\z/', '', $codeblock);

Michelf/MarkdownExtra.php

@@ -42,9 +42,6 @@ class MarkdownExtra extends \Michelf\Markdown {
 	# Class attribute for code blocks goes on the `code` tag;
 	# setting this to true will put attributes on the `pre` tag instead.
 	public $code_attr_on_pre = false;
-	
-	# Optional content function for code blocks
-	public $code_block_content_func = null;
 
 	# Predefined abbreviations.
 	public $predef_abbr = array();
@@ -138,7 +135,7 @@ class MarkdownExtra extends \Michelf\Markdown {
 	# Expression to use when parsing in a context when no capture is desired
 	protected $id_class_attr_nocatch_re = '\{(?:[ ]*[#.a-z][-_:a-zA-Z0-9=]+){1,}[ ]*\}';
 
-	protected function doExtraAttributes($tag_name, $attr, $defaultIdValue = null) {
+	protected function doExtraAttributes($tag_name, $attr, $defaultIdValue = null, $classes = array()) {
 	#
 	# Parse attributes caught by the $this->id_class_attr_catch_re expression
 	# and return the HTML-formatted list of attributes.
@@ -148,14 +145,13 @@ class MarkdownExtra extends \Michelf\Markdown {
 	# In addition, this method also supports supplying a default Id value,
 	# which will be used to populate the id attribute in case it was not
 	# overridden.
-		if (empty($attr) && !$defaultIdValue) return "";
+		if (empty($attr) && !$defaultIdValue && empty($classes)) return "";
 		
 		# Split on components
 		preg_match_all('/[#.a-z][-_:a-zA-Z0-9=]+/', $attr, $matches);
 		$elements = $matches[0];
 
 		# handle classes and ids (only first id taken into account)
-		$classes = array();
 		$attributes = array();
 		$id = false;
 		foreach ($elements as $element) {
@@ -352,12 +348,10 @@ class MarkdownExtra extends \Michelf\Markdown {
 					# Fenced code block marker
 					(?<= ^ | \n )
 					[ ]{0,'.($indent+3).'}(?:~{3,}|`{3,})
-									[ ]*
-					(?:
-					\.?[-_:a-zA-Z0-9]+ # standalone class name
-					|
-						'.$this->id_class_attr_nocatch_re.' # extra attributes
-					)?
+					[ ]*
+					(?: \.?[-_:a-zA-Z0-9]+ )? # standalone class name
+					[ ]*
+					(?: '.$this->id_class_attr_nocatch_re.' )? # extra attributes
 					[ ]*
 					(?= \n )
 				' : '' ). ' # End (if not is span).
@@ -413,7 +407,7 @@ class MarkdownExtra extends \Michelf\Markdown {
 			# Note: need to recheck the whole tag to disambiguate backtick
 			# fences from code spans
 			#
-			if (preg_match('{^\n?([ ]{0,'.($indent+3).'})(~{3,}|`{3,})[ ]*(?:\.?[-_:a-zA-Z0-9]+|'.$this->id_class_attr_nocatch_re.')?[ ]*\n?$}', $tag, $capture)) {
+			if (preg_match('{^\n?([ ]{0,'.($indent+3).'})(~{3,}|`{3,})[ ]*(?:\.?[-_:a-zA-Z0-9]+)?[ ]*(?:'.$this->id_class_attr_nocatch_re.')?[ ]*\n?$}', $tag, $capture)) {
 				# Fenced code block marker: find matching end marker.
 				$fence_indent = strlen($capture[1]); # use captured indent in re
 				$fence_re = $capture[2]; # use captured fence in re
@@ -1333,13 +1327,13 @@ class MarkdownExtra extends \Michelf\Markdown {
 		$codeblock = preg_replace_callback('/^\n+/',
 			array($this, '_doFencedCodeBlocks_newlines'), $codeblock);
 
+		$classes = array();
 		if ($classname != "") {
 			if ($classname{0} == '.')
 				$classname = substr($classname, 1);
-			$attr_str = ' class="'.$this->code_class_prefix.$classname.'"';
-		} else {
-			$attr_str = $this->doExtraAttributes($this->code_attr_on_pre ? "pre" : "code", $attrs);
+			$classes[] = $this->code_class_prefix.$classname;
 		}
+		$attr_str = $this->doExtraAttributes($this->code_attr_on_pre ? "pre" : "code", $attrs, null, $classes);
 		$pre_attr_str  = $this->code_attr_on_pre ? $attr_str : '';
 		$code_attr_str = $this->code_attr_on_pre ? '' : $attr_str;
 		$codeblock  = "<pre$pre_attr_str><code$code_attr_str>$codeblock</code></pre>";

Readme.md

@@ -174,6 +174,20 @@ PHP Markdown, please visit [michelf.ca/donate] or send Bitcoin to
 Version History
 ---------------
 
+Current Version
+
+*	For fenced code blocks in Markdown Extra, can now set a class name for the 
+	code block's language before the special attribute block. Previously, this 
+	class name was only allowed in the absence of the special attribute block.
+
+*	Added a `code_block_content_func` configuration variable which takes a 
+	function that will convert the content of the code block to HTML. This is 
+	most useful for syntax highlighting. For fenced code blocks in Markdown 
+	Extra, the function has access to the language class name (the one outside 
+	of the special attribute block). Credits to Mario Konrad for providing the 
+	implementation.
+
+
 PHP Markdown Lib 1.5.0 (1 Mar 2015)
 
 *	Added the ability start ordered lists with a number different from 1 and