enh(markdown) much improved markdown support

CHANGES.md

@@ -14,6 +14,8 @@ Core Changes:
 
 Language Improvements:
 
+- (markdown) much improved code block support (#2382) [Josh Goebel][]
+- (markdown) improve bold/italic nesting (#2382) [Josh Goebel][]
 - (fortran) Add Fortran 2018 keywords and coarray intrinsics (#2361) [Sam Miller][]
 - (delphi) highlight hexadecimal, octal, and binary numbers (#2370) [Robert Riebisch]()
 - enh(plaintext) added `text` and `txt` as alias (#2360) [Taufik Nurrohman][]
@@ -22,6 +24,7 @@ Developer Tools:
 
 - none.
 
+[Josh Goebel]: https://github.com/yyyc514
 [Sam Miller]: https://github.com/smillerc
 [Robert Riebisch]: https://github.com/bttrx
 [Taufik Nurrohman]: https://github.com/taufik-nurrohman

src/languages/dart.js

@@ -92,7 +92,8 @@ function(hljs) {
       hljs.COMMENT(
         '/\\*\\*',
         '\\*/', {
-          subLanguage: 'markdown'
+          subLanguage: 'markdown',
+          relevance:0
         }
       ),
       hljs.COMMENT(
@@ -102,6 +103,7 @@ function(hljs) {
             subLanguage: 'markdown',
             begin: '.',
             end: '$',
+            relevance:0
           }]
         }
       ),

src/languages/markdown.js

@@ -7,109 +7,148 @@ Category: common, markup
 */
 
 function(hljs) {
-  return {
-    aliases: ['md', 'mkdown', 'mkd'],
-    contains: [
-      // highlight headers
-      {
-        className: 'section',
-        variants: [
-          { begin: '^#{1,6}', end: '$' },
-          { begin: '^.+?\\n[=-]{2,}$' }
-        ]
-      },
-      // inline html
+  INLINE_HTML = {
+    begin: '<', end: '>',
+    subLanguage: 'xml',
+    relevance: 0
+  };
+  HORIZONTAL_RULE = {
+    begin: '^[-\\*]{3,}', end: '$'
+  };
+  CODE = {
+    className: 'code',
+    variants: [
+      // TODO: fix to allow these to work with sublanguage also
+      { begin: '(`{3,})(.|\\n)*?\\1`*[ ]*', },
+      { begin: '(~{3,})(.|\\n)*?\\1~*[ ]*', },
+      // needed to allow markdown as a sublanguage to work
+      { begin: '```', end: '```+[ ]*$' },
+      { begin: '~~~', end: '~~~+[ ]*$' },
+      { begin: '`.+?`' },
       {
-        begin: '<', end: '>',
-        subLanguage: 'xml',
+        begin: '(?=^( {4}|\\t))',
+        // use contains to gobble up multiple lines to allow the block to be whatever size
+        // but only have a single open/close tag vs one per line
+        contains: [
+          { begin: '^( {4}|\\t)', end: '(\\n)$' }
+        ],
         relevance: 0
-      },
-      // lists (indicators only)
+      }
+    ]
+  };
+  LIST = {
+    className: 'bullet',
+    begin: '^[ \t]*([*+-]|(\\d+\\.))(?=\\s+)',
+    end: '\\s+',
+    excludeEnd: true
+  };
+  LINK_REFERENCE = {
+    begin: /^\[[^\n]+\]:/,
+    returnBegin: true,
+    contains: [
       {
-        className: 'bullet',
-        begin: '^\\s*([*+-]|(\\d+\\.))\\s+'
+        className: 'symbol',
+        begin: /\[/, end: /\]/,
+        excludeBegin: true, excludeEnd: true
       },
-      // strong segments
       {
-        className: 'strong',
-        begin: '[*_]{2}.+?[*_]{2}'
-      },
-      // emphasis segments
+        className: 'link',
+        begin: /:\s*/, end: /$/,
+        excludeBegin: true
+      }
+    ]
+  };
+  LINK = {
+    begin: '\\[.+?\\][\\(\\[].*?[\\)\\]]',
+    returnBegin: true,
+    contains: [
       {
-        className: 'emphasis',
-        variants: [
-          { begin: '\\*.+?\\*' },
-          { begin: '_.+?_'
-          , relevance: 0
-          }
-        ]
+        className: 'string',
+        begin: '\\[', end: '\\]',
+        excludeBegin: true,
+        returnEnd: true,
+        relevance: 0
       },
-      // blockquotes
       {
-        className: 'quote',
-        begin: '^>\\s+', end: '$'
+        className: 'link',
+        begin: '\\]\\(', end: '\\)',
+        excludeBegin: true, excludeEnd: true
       },
-      // code snippets
       {
-        className: 'code',
-        variants: [
-          {
-            begin: '^```\\w*\\s*$', end: '^```[ ]*$'
-          },
-          {
-            begin: '`.+?`'
-          },
-          {
-            begin: '^( {4}|\\t)', end: '$',
-            relevance: 0
-          }
-        ]
-      },
-      // horizontal rules
-      {
-        begin: '^[-\\*]{3,}', end: '$'
-      },
-      // using links - title and link
+        className: 'symbol',
+        begin: '\\]\\[', end: '\\]',
+        excludeBegin: true, excludeEnd: true
+      }
+    ],
+    relevance: 10
+  };
+  BOLD = {
+    className: 'strong',
+    contains: [],
+    variants: [
+      {begin: /_{2}/, end: /_{2}/ },
+      {begin: /\*{2}/, end: /\*{2}/ }
+    ]
+  };
+  ITALIC = {
+    className: 'emphasis',
+    contains: [],
+    variants: [
+      { begin: /\*(?!\*)/, end: /\*/ },
+      { begin: /_(?!_)/, end: /_/, relevance: 0},
+    ]
+  };
+  BOLD.contains.push(ITALIC);
+  ITALIC.contains.push(BOLD);
+
+  CONTAINABLE = [
+    INLINE_HTML,
+    LINK
+  ];
+
+  BOLD.contains = BOLD.contains.concat(CONTAINABLE);
+  ITALIC.contains = ITALIC.contains.concat(CONTAINABLE);
+
+  CONTAINABLE = CONTAINABLE.concat(BOLD,ITALIC);
+
+  HEADER = {
+    className: 'section',
+    variants: [
       {
-        begin: '\\[.+?\\][\\(\\[].*?[\\)\\]]',
-        returnBegin: true,
-        contains: [
-          {
-            className: 'string',
-            begin: '\\[', end: '\\]',
-            excludeBegin: true,
-            returnEnd: true,
-            relevance: 0
-          },
-          {
-            className: 'link',
-            begin: '\\]\\(', end: '\\)',
-            excludeBegin: true, excludeEnd: true
-          },
-          {
-            className: 'symbol',
-            begin: '\\]\\[', end: '\\]',
-            excludeBegin: true, excludeEnd: true
-          }
-        ],
-        relevance: 10
-      },
+        begin: '^#{1,6}',
+        end: '$',
+        contains: CONTAINABLE
+       },
       {
-        begin: /^\[[^\n]+\]:/,
-        returnBegin: true,
+        begin: '(?=^.+?\\n[=-]{2,}$)',
         contains: [
-          {
-            className: 'symbol',
-            begin: /\[/, end: /\]/,
-            excludeBegin: true, excludeEnd: true
-          },
-          {
-            className: 'link',
-            begin: /:\s*/, end: /$/,
-            excludeBegin: true
-          }
+          { begin: '^[=-]*$' },
+          { begin: '^', end: "\\n", contains: CONTAINABLE },
         ]
-      }
+       }
+    ]
+  };
+
+  BLOCKQUOTE = {
+    className: 'quote',
+    begin: '^>\\s+',
+    contains: CONTAINABLE,
+    end: '$',
+  };
+
+  return {
+    aliases: ['md', 'mkdown', 'mkd'],
+    contains: [
+      HEADER,
+      INLINE_HTML,
+      LIST,
+      BOLD,
+      ITALIC,
+      BLOCKQUOTE,
+      CODE,
+      HORIZONTAL_RULE,
+      LINK,
+      LINK_REFERENCE
     ]
   };
 }

test/markup/markdown/bold_italics.expect.txt

@@ -0,0 +1,18 @@
+<span class="hljs-emphasis">_Italic_</span>
+<span class="hljs-emphasis">*Italic*</span>
+<span class="hljs-strong">__Bold__</span>
+<span class="hljs-strong">**Bold**</span>
+<span class="hljs-emphasis">*Is <span class="hljs-strong">__Combined__</span>*</span>
+<span class="hljs-strong">__Bold <span class="hljs-emphasis">*then italic*</span>__</span>
+<span class="hljs-strong">**Bold <span class="hljs-emphasis">_then italic_</span>**</span>
+<span class="hljs-strong">**Bold and <span class="xml"><span class="hljs-tag">&lt;<span class="hljs-name">br</span>/&gt;</span></span>**</span>
+<span class="hljs-strong">**<span class="hljs-emphasis">_[<span class="hljs-string">this</span>](<span class="hljs-link">https://google.com</span>)_</span>**</span>
+
+<span class="hljs-quote">&gt; quoted <span class="hljs-strong">**Bold <span class="hljs-emphasis">_then italic_</span>**</span></span>
+<span class="hljs-quote">&gt; <span class="hljs-emphasis">_[<span class="hljs-string">this</span>](<span class="hljs-link">https://google.com</span>)_</span></span>
+
+  <span class="hljs-emphasis">*this is a emphasized paragraph*</span>
+  <span class="hljs-emphasis">*this is too*</span>
+
+<span class="hljs-bullet">*</span> list with a <span class="hljs-emphasis">*italic item*</span>
+<span class="hljs-bullet">*</span> list with a <span class="hljs-strong">**bold item**</span>

test/markup/markdown/bold_italics.txt

@@ -0,0 +1,18 @@
+_Italic_
+*Italic*
+__Bold__
+**Bold**
+*Is __Combined__*
+__Bold *then italic*__
+**Bold _then italic_**
+**Bold and <br/>**
+**_[this](https://google.com)_**
+
+> quoted **Bold _then italic_**
+> _[this](https://google.com)_
+
+  *this is a emphasized paragraph*
+  *this is too*
+
+* list with a *italic item*
+* list with a **bold item**

test/markup/markdown/code.expect.txt

@@ -1,8 +1,38 @@
-<span class="hljs-code">    var code = true;</span>
-
+<span class="hljs-code">    var code = true;
+    var code = false;
+</span>
 
 <span class="hljs-code">```javascript
 var code = true;
 ```</span>
 
+<span class="hljs-code">````md
+```
+a = 'This is a code block in python'
+```
+````</span>
+
+<span class="hljs-code">~~~
+tilde can be used also (github)
+~~~</span>
+
+<span class="hljs-code">~~~~    ruby startline=3 $%@#$
+def foo(x)
+  return 3
+end
+~~~~~~~</span>
+
+<span class="hljs-code">~~~~~~~something
+code  here
+~~~~~~~</span>
+
+<span class="hljs-code">```
+aaa
+~~~
+```</span>
+
+  <span class="hljs-code">```javascript
+  can be indented
+  ```</span>
+
 Inline <span class="hljs-code">`code`</span>, and <span class="hljs-code">`more code`</span>.

test/markup/markdown/code.txt

@@ -1,8 +1,38 @@
     var code = true;
+    var code = false;
 
 
 ```javascript
 var code = true;
 ```
 
+````md
+```
+a = 'This is a code block in python'
+```
+````
+
+~~~
+tilde can be used also (github)
+~~~
+
+~~~~    ruby startline=3 $%@#$
+def foo(x)
+  return 3
+end
+~~~~~~~
+
+~~~~~~~something
+code  here
+~~~~~~~
+
+```
+aaa
+~~~
+```
+
+  ```javascript
+  can be indented
+  ```
+
 Inline `code`, and `more code`.