feat: add prism highlight support

lib/hexo/default_config.js

@@ -48,6 +48,12 @@ module.exports = {
     wrap: true,
     hljs: false
   },
+  prismjs: {
+    enable: false,
+    preprocess: true,
+    line_number: true,
+    tab_replace: ''
+  },
   // Category & Tag
   default_category: 'uncategorized',
   category_map: {},

lib/plugins/filter/before_post_render/backtick_code_block.js

@@ -1,51 +1,38 @@
 'use strict';
 
-const { highlight } = require('hexo-util');
+let highlight, prismHighlight;
 
 const rBacktick = /^((?:[^\S\r\n]*>){0,3}[^\S\r\n]*)(`{3,}|~{3,})[^\S\r\n]*((?:.*?[^`\s])?)[^\S\r\n]*\n((?:[\s\S]*?\n)?)(?:(?:[^\S\r\n]*>){0,3}[^\S\r\n]*)\2(\n+|$)/gm;
 const rAllOptions = /([^\s]+)\s+(.+?)\s+(https?:\/\/\S+|\/\S+)\s*(.+)?/;
 const rLangCaption = /([^\s]+)\s*(.+)?/;
 
+const escapeSwigTag = str => str.replace(/{/g, '{').replace(/}/g, '}');
+
 function backtickCodeBlock(data) {
-  const config = this.config.highlight || {};
-  if (!config.enable) return;
+  const hljsCfg = this.config.highlight || {};
+  const prismCfg = this.config.prismjs || {};
+
   data.content = data.content.replace(rBacktick, ($0, start, $2, _args, _content, end) => {
     let content = _content.replace(/\n$/, '');
-    const args = _args.split('=').shift();
-
-    const options = {
-      hljs: config.hljs,
-      autoDetect: config.auto_detect,
-      gutter: config.line_number,
-      tab: config.tab_replace,
-      wrap: config.wrap
-    };
 
-    if (options.gutter) {
-      config.first_line_number = config.first_line_number || 'always1';
-      if (config.first_line_number === 'inline') {
+    // neither highlight or prismjs is enabled, return escaped content directly.
+    if (!hljsCfg.enable && !prismCfg.enable) return escapeSwigTag($0);
 
-        // setup line number by inline
-        _args = _args.replace('=+', '=');
-        options.gutter = _args.includes('=');
-
-        // setup fiestLineNumber;
-        options.firstLine = options.gutter ? _args.split('=')[1] || 1 : 0;
-      }
-    }
+    // Extrace langauge and caption of code blocks
+    const args = _args.split('=').shift();
+    let lang, caption;
 
     if (args) {
       const match = rAllOptions.exec(args) || rLangCaption.exec(args);
 
-
       if (match) {
-        options.lang = match[1];
+        lang = match[1];
 
         if (match[2]) {
-          options.caption = `<span>${match[2]}</span>`;
+          caption = `<span>${match[2]}</span>`;
 
           if (match[3]) {
-            options.caption += `<a href="${match[3]}">${match[4] ? match[4] : 'link'}</a>`;
+            caption += `<a href="${match[3]}">${match[4] ? match[4] : 'link'}</a>`;
           }
         }
       }
@@ -59,11 +46,52 @@ function backtickCodeBlock(data) {
       content = content.replace(regexp, '');
     }
 
-    content = highlight(content, options)
-      .replace(/{/g, '&#123;')
-      .replace(/}/g, '&#125;');
+    // Since prismjs have better performance, so prismjs should have higher priority.
+    if (prismCfg.enable) {
+      if (!prismHighlight) prismHighlight = require('hexo-util').prismHighlight;
+
+      const options = {
+        lineNumber: prismCfg.line_number,
+        tab: prismCfg.tab_replace,
+        isPreprocess: prismCfg.preprocess,
+        lang
+      };
+
+      content = prismHighlight(content, options);
+    } else if (hljsCfg.enable) {
+      if (!highlight) highlight = require('hexo-util').highlight;
+
+      const options = {
+        hljs: hljsCfg.hljs,
+        autoDetect: hljsCfg.auto_detect,
+        gutter: hljsCfg.line_number,
+        tab: hljsCfg.tab_replace,
+        wrap: hljsCfg.wrap,
+        lang,
+        caption
+      };
+
+      if (options.gutter) {
+        hljsCfg.first_line_number = hljsCfg.first_line_number || 'always1';
+        if (hljsCfg.first_line_number === 'inline') {
+
+          // setup line number by inline
+          _args = _args.replace('=+', '=');
+          options.gutter = _args.includes('=');
+
+          // setup firstLineNumber;
+          options.firstLine = options.gutter ? _args.split('=')[1] || 1 : 0;
+        }
+      }
+
+      content = highlight(content, options);
+    }
 
-    return `${start}<!--hexoPostRenderEscape:${content}:hexoPostRenderEscape-->${end}`;
+    return start
+      + '<!--hexoPostRenderEscape:'
+      + escapeSwigTag(content)
+      + ':hexoPostRenderEscape-->'
+      + end;
   });
 }
 

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;');
 };

lib/plugins/tag/include_code.js

@@ -2,7 +2,7 @@
 
 const fs = require('hexo-fs');
 const { basename, extname, join } = require('path');
-const { highlight } = require('hexo-util');
+const { highlight, prismHighlight } = require('hexo-util');
 
 const rCaptionTitleFile = /(.*)?(?:\s+|^)(\/*\S+)/;
 const rLang = /\s*lang:(\w+)/i;
@@ -17,7 +17,6 @@ const rTo = /\s*to:(\d+)/i;
 */
 
 module.exports = ctx => function includeCodeTag(args) {
-  const config = ctx.config.highlight || {};
   let codeDir = ctx.config.code_dir;
   let arg = args.join(' ');
 
@@ -47,22 +46,31 @@ module.exports = ctx => function includeCodeTag(args) {
 
   const path = match[2];
 
-  // If the title is not defined, use file name instead
-  const title = match[1] || basename(path);
-
   // If the language is not defined, use file extension instead
   lang = lang || extname(path).substring(1);
 
   const src = join(ctx.source_dir, codeDir, path);
 
+  // If the title is not defined, use file name instead
+  const title = match[1] || basename(path);
   const caption = `<span>${title}</span><a href="${ctx.config.root}${codeDir}${path}">view raw</a>`;
 
-  const options = {
+  const hljsCfg = ctx.config.highlight || {};
+  const prismjsCfg = ctx.config.prismjs || {};
+
+  const hljsOptions = {
     lang,
     caption,
-    gutter: config.line_number,
-    hljs: config.hljs,
-    tab: config.tab_replace
+    gutter: hljsCfg.line_number,
+    hljs: hljsCfg.hljs,
+    tab: hljsCfg.tab_replace
+  };
+
+  const prismjsOptions = {
+    lang,
+    lineNumber: prismjsCfg.line_number,
+    tab: prismjsCfg.tab_replace,
+    isPreprocess: prismjsCfg.preprocess
   };
 
   return fs.exists(src).then(exist => {
@@ -73,10 +81,12 @@ module.exports = ctx => function includeCodeTag(args) {
     const lines = code.split('\n');
     code = lines.slice(from, to).join('\n').trim();
 
-    if (!config.enable) {
-      return `<pre><code>${code}</code></pre>`;
+    if (prismjsCfg.enable) {
+      return prismHighlight(code, prismjsOptions);
+    } else if (hljsCfg.enable) {
+      return highlight(code, hljsOptions);
     }
 
-    return highlight(code, options);
+    return `<pre><code>${code}</code></pre>`;
   });
 };