support for mermaid containers

README.md

@@ -113,6 +113,19 @@ stateDiagram
 ```
 </pre>
 
+or
+
+<pre>
+::: mermaid
+stateDiagram
+    [*] --> First
+    state First {
+        [*] --> second
+        second --> [*]
+    }
+:::
+</pre>
+
 OUTPUT
 
 ![mermaid](images/mermaid.png)

extension.js

@@ -253,6 +253,48 @@ function convertMarkdownToHtml(filename, type, text) {
 
   // markdown-it-container
   // https://github.com/markdown-it/markdown-it-container
+
+  const pluginKeyword = 'mermaid';
+  const tokenTypeInline = 'inline';
+  const ttContainerOpen = 'container_' + pluginKeyword + '_open';
+  const ttContainerClose = 'container_' + pluginKeyword + '_close';
+  const empty = [];
+
+  md.use(require('markdown-it-container'), pluginKeyword, {
+    validate: (info) => {
+      return info.trim() === pluginKeyword;
+    },
+
+    render: (tokens, idx) => {
+      var token = tokens[idx];
+
+      var src = '';
+      if (token.type === ttContainerOpen) {
+          for (var i = idx + 1; i < tokens.length; i++) {
+              var value = tokens[i]
+              if (value === undefined || value.type === ttContainerClose) {
+                  break;
+              }
+              src += value.content;
+              if (value.block && value.nesting <= 0) {
+                  src += '\n';
+              }
+              // Clear these out so markdown-it doesn't try to render them
+              value.tag = '';
+              value.type = tokenTypeInline;
+              value.content = ''; 
+              value.children = empty;
+          }
+      }
+
+      if (token.nesting === 1) {
+          return `<div class="${pluginKeyword}">${md.utils.escapeHtml(src)}`;
+      } else {
+          return '</div>\n';
+      }
+    }
+  });
+
   md.use(require('markdown-it-container'), '', {
     validate: function (name) {
       return name.trim().length;

test/suite/mermaid.md

@@ -8,3 +8,12 @@ graph TD
     C -->|Two| E[iPhone]
     C -->|Three| F[Car]
 ```
+
+::: mermaid
+graph TD
+    A[Christmas] -->|Get money| B(Go shopping)
+    B --> C{Let me think}
+    C -->|One| D[Laptop]
+    C -->|Two| E[iPhone]
+    C -->|Three| F[Car]
+:::