refactor/feat(tag/code): bring up prismjs again

lib/plugins/tag/code.js

@@ -2,7 +2,7 @@
 
 // Based on: https://raw.github.com/imathis/octopress/master/plugins/code_block.rb
 
-const { escapeHTML, highlight } = require('hexo-util');
+const { escapeHTML, highlight, prismHighlight } = require('hexo-util');
 
 const rCaptionUrlTitle = /(\S[\S\s]*)\s+(https?:\/\/\S+)\s+(.+)/i;
 const rCaptionUrl = /(\S[\S\s]*)\s+(https?:\/\/\S+)/i;
@@ -25,13 +25,13 @@ const rCaption = /\S[\S\s]*/;
  * Example: `mark:1,4-7,10` will mark line 1, 4 to 7 and 10.
  * @param {Object} wrap Wrap the code block in <table>, value must be a boolean
  * @returns {String} Code snippet with code highlighting
- */
+*/
 
-function getHighlightOptions(config, args) {
+function parseArgs(args) {
   const _else = [];
   const len = args.length;
-  let lang = '';
-  let { line_number, wrap } = config;
+  let lang,
+    line_number, wrap;
   let firstLine = 1;
   const mark = [];
   for (let i = 0; i < len; i++) {
@@ -86,8 +86,9 @@ function getHighlightOptions(config, args) {
   }
 
   const arg = _else.join(' ');
-  let caption = '';
-  let match;
+  // eslint-disable-next-line one-var
+  let match, caption = '';
+
   if ((match = arg.match(rCaptionUrlTitle)) != null) {
     caption = `<span>${match[1]}</span><a href="${match[2]}">${match[3]}</a>`;
   } else if ((match = arg.match(rCaptionUrl)) != null) {
@@ -100,37 +101,60 @@ function getHighlightOptions(config, args) {
     lang,
     firstLine,
     caption,
-    gutter: line_number,
-    hljs: config.hljs,
+    line_number,
     mark,
-    tab: config.tab_replace,
-    autoDetect: config.auto_detect,
     wrap
   };
 }
 
 module.exports = ctx => function codeTag(args, content) {
-  const config = ctx.config.highlight || {};
-  let { enable } = config;
+  const hljsCfg = ctx.config.highlight || {};
+  const prismjsCfg = ctx.config.prismjs || {};
 
   let index;
+  let enableHighlight = true;
 
   if ((index = args.findIndex(item => item.startsWith('highlight:'))) !== -1) {
     const arg = args[index];
-    const _enable = arg.slice(10);
-    enable = _enable === 'true';
+    const highlightStr = arg.slice(10);
+    enableHighlight = highlightStr === 'true';
     args.splice(index, 1);
   }
 
-  if (!enable) {
-    content = escapeHTML(content);
-    return `<pre><code>${content}</code></pre>`;
+  // If 'hilight: false' is given, return escaped code directly
+  // If neither highlight.js nor prism.js is enabled, return escaped code directly
+  if (!enableHighlight || (!hljsCfg.enable && !prismjsCfg.enable)) {
+    return `<pre><code>${escapeHTML(content)}</code></pre>`;
   }
 
-  content = highlight(content, getHighlightOptions(config, args));
-
-  content = content.replace(/{/g, '&#123;')
-    .replace(/}/g, '&#125;');
+  const { lang, firstLine, caption, line_number, mark, wrap } = parseArgs(args);
+
+  if (prismjsCfg.enable) {
+    const prismjsOption = {
+      lang,
+      firstLine,
+      lineNumber: typeof line_number !== 'undefined' ? line_number : prismjsCfg.line_number,
+      mark,
+      tab: prismjsCfg.tab_replace,
+      isPreprocess: prismjsCfg.preprocess
+    };
+
+    content = prismHighlight(content, prismjsOption);
+  } else {
+    const hljsOption = {
+      lang: typeof lang !== 'undefined' ? lang : '',
+      firstLine,
+      caption,
+      gutter: typeof line_number !== 'undefined' ? line_number : hljsCfg.line_number,
+      hljs: hljsCfg.hljs,
+      mark,
+      tab: hljsCfg.tab_replace,
+      autoDetect: hljsCfg.auto_detect,
+      wrap: typeof wrap === 'undefined' ? wrap : hljsCfg.wrap
+    };
+
+    content = highlight(content, hljsOption);
+  }
 
-  return content;
+  return content.replace(/{/g, '&#123;').replace(/}/g, '&#125;');
 };