refactor highlight: add extend api for highlight

lib/extend/index.js

@@ -5,12 +5,13 @@ const Deployer = require('./deployer');
 const Filter = require('./filter');
 const Generator = require('./generator');
 const Helper = require('./helper');
+const Highlight = require('./syntax_highlight');
 const Injector = require('./injector');
 const Migrator = require('./migrator');
 const Processor = require('./processor');
 const Renderer = require('./renderer');
 const Tag = require('./tag');
 
 module.exports = {
-  Console, Deployer, Filter, Generator, Helper, Injector, Migrator, Processor, Renderer, Tag
+  Console, Deployer, Filter, Generator, Helper, Highlight, Injector, Migrator, Processor, Renderer, Tag
 };

lib/extend/syntax_highlight.js

@@ -0,0 +1,29 @@
+'use strict';
+
+class SyntaxHighlight {
+  constructor() {
+    this.store = {};
+  }
+
+  register(name, fn) {
+    if (typeof fn !== 'function') throw new TypeError('fn must be a function');
+
+    this.store[name] = fn;
+  }
+
+  query(name) {
+    return name && this.store[name];
+  }
+
+  exec(name, options) {
+    const fn = this.store[name];
+
+    if (!fn) throw new TypeError(`syntax highlighter ${name} is not registered`);
+    const ctx = options.context;
+    const args = options.args || [];
+
+    return Reflect.apply(fn, ctx, args);
+  }
+}
+
+module.exports = SyntaxHighlight;

lib/hexo/default_config.js

@@ -40,8 +40,8 @@ module.exports = {
   post_asset_folder: false,
   relative_link: false,
   future: true,
+  syntax_highlighter: 'highlight.js',
   highlight: {
-    enable: true,
     auto_detect: false,
     line_number: true,
     tab_replace: '',
@@ -51,7 +51,6 @@ module.exports = {
     hljs: false
   },
   prismjs: {
-    enable: false,
     preprocess: true,
     line_number: true,
     tab_replace: ''

lib/hexo/index.js

@@ -11,7 +11,7 @@ const Module = require('module');
 const { runInThisContext } = require('vm');
 const { version } = require('../../package.json');
 const { logger } = require('hexo-log');
-const { Console, Deployer, Filter, Generator, Helper, Injector, Migrator, Processor, Renderer, Tag } = require('../extend');
+const { Console, Deployer, Filter, Generator, Helper, Highlight, Injector, Migrator, Processor, Renderer, Tag } = require('../extend');
 const Render = require('./render');
 const registerModels = require('./register_models');
 const Post = require('./post');
@@ -123,6 +123,7 @@ class Hexo extends EventEmitter {
       filter: new Filter(),
       generator: new Generator(),
       helper: new Helper(),
+      highlight: new Highlight(),
       injector: new Injector(),
       migrator: new Migrator(),
       processor: new Processor(),
@@ -224,6 +225,7 @@ class Hexo extends EventEmitter {
     require('../plugins/filter')(this);
     require('../plugins/generator')(this);
     require('../plugins/helper')(this);
+    require('../plugins/highlight')(this);
     require('../plugins/injector')(this);
     require('../plugins/processor')(this);
     require('../plugins/renderer')(this);

lib/hexo/post.js

@@ -417,7 +417,7 @@ class Post {
       }
 
       const options = data.markdown || {};
-      if (!config.highlight.enable) options.highlight = null;
+      if (!config.syntax_highlighter) options.highlight = null;
 
       ctx.log.debug('Rendering post: %s', magenta(source));
       // Render with markdown or other renderer

lib/plugins/filter/before_post_render/backtick_code_block.js

@@ -1,111 +1,73 @@
 'use strict';
 
-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[^\S\r\n]?(\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 dataContent = data.content;
-
-  const hljsCfg = this.config.highlight || {};
-  const prismCfg = this.config.prismjs || {};
+module.exports = ctx => {
+  return function backtickCodeBlock(data) {
+    const dataContent = data.content;
 
-  if ((!dataContent.includes('```') && !dataContent.includes('~~~')) || (!hljsCfg.enable && !prismCfg.enable)) return;
+    if ((!dataContent.includes('```') && !dataContent.includes('~~~')) || !ctx.extend.highlight.query(ctx.config.syntax_highlighter)) return;
 
-  data.content = dataContent.replace(rBacktick, ($0, start, $2, _args, _content, end) => {
-    let content = _content.replace(/\n$/, '');
+    data.content = dataContent.replace(rBacktick, ($0, start, $2, _args, _content, end) => {
+      let content = _content.replace(/\n$/, '');
 
-    // neither highlight or prismjs is enabled, return escaped content directly.
-    if (!hljsCfg.enable && !prismCfg.enable) return escapeSwigTag($0);
+      // neither highlight or prismjs is enabled, return escaped content directly.
+      if (!ctx.extend.highlight.query(ctx.config.syntax_highlighter)) return escapeSwigTag($0);
 
-    // Extract language and caption of code blocks
-    const args = _args.split('=').shift();
-    let lang, caption;
+      // Extract language and caption of code blocks
+      const args = _args.split('=').shift();
+      let lang, caption;
 
-    if (args) {
-      const match = rAllOptions.exec(args) || rLangCaption.exec(args);
+      if (args) {
+        const match = rAllOptions.exec(args) || rLangCaption.exec(args);
 
-      if (match) {
-        lang = match[1];
+        if (match) {
+          lang = match[1];
 
-        if (match[2]) {
-          caption = `<span>${match[2]}</span>`;
+          if (match[2]) {
+            caption = `<span>${match[2]}</span>`;
 
-          if (match[3]) {
-            caption += `<a href="${match[3]}">${match[4] ? match[4] : 'link'}</a>`;
+            if (match[3]) {
+              caption += `<a href="${match[3]}">${match[4] ? match[4] : 'link'}</a>`;
+            }
           }
         }
       }
-    }
-
-    // PR #3765
-    if (start.includes('>')) {
-      // heading of last line is already removed by the top RegExp "rBacktick"
-      const depth = start.split('>').length - 1;
-      const regexp = new RegExp(`^([^\\S\\r\\n]*>){0,${depth}}([^\\S\\r\\n]|$)`, 'mg');
-      content = content.replace(regexp, '');
-    }
 
-    // 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,
-        caption
-      };
-
-      content = prismHighlight(content, options);
-    } else if (hljsCfg.enable) {
-      if (!highlight) highlight = require('hexo-util').highlight;
+      // PR #3765
+      if (start.includes('>')) {
+        // heading of last line is already removed by the top RegExp "rBacktick"
+        const depth = start.split('>').length - 1;
+        const regexp = new RegExp(`^([^\\S\\r\\n]*>){0,${depth}}([^\\S\\r\\n]|$)`, 'mg');
+        content = content.replace(regexp, '');
+      }
 
       const options = {
-        hljs: hljsCfg.hljs,
-        autoDetect: hljsCfg.auto_detect,
-        gutter: hljsCfg.line_number,
-        tab: hljsCfg.tab_replace,
-        wrap: hljsCfg.wrap,
         lang,
-        languageAttr: hljsCfg.language_attr,
-        caption
+        caption,
+        lines_length: content.split('\n').length
       };
+      // setup line number by inline
+      _args = _args.replace('=+', '=');
 
-      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;
-        }
-      }
-
-      if (Array.isArray(hljsCfg.exclude_languages) && hljsCfg.exclude_languages.includes(options.lang)) {
-        // Only wrap with <pre><code class="lang"></code></pre>
-        options.wrap = false;
-        options.gutter = false;
-        options.autoDetect = false;
+      // setup firstLineNumber;
+      if (_args.includes('=')) {
+        options.firstLineNumber = _args.split('=')[1] || 1;
       }
-
-      content = highlight(content, options);
-    }
-
-    return start
-      + '<hexoPostRenderCodeBlock>'
-      + escapeSwigTag(content)
-      + '</hexoPostRenderCodeBlock>'
-      + end;
-  });
-}
-
-module.exports = backtickCodeBlock;
+      content = ctx.extend.highlight.exec(ctx.config.syntax_highlighter, {
+        context: ctx,
+        args: [content, options]
+      });
+
+      return start
+        + '<hexoPostRenderCodeBlock>'
+        + escapeSwigTag(content)
+        + '</hexoPostRenderCodeBlock>'
+        + end;
+    });
+  };
+};

lib/plugins/filter/before_post_render/index.js

@@ -3,6 +3,6 @@
 module.exports = ctx => {
   const { filter } = ctx.extend;
 
-  filter.register('before_post_render', require('./backtick_code_block'));
+  filter.register('before_post_render', require('./backtick_code_block')(ctx));
   filter.register('before_post_render', require('./titlecase'));
 };

lib/plugins/highlight/highlight.js

@@ -0,0 +1,44 @@
+'use strict';
+
+// Lazy require highlight.js
+let highlight;
+
+module.exports = function highlightFilter(code, options) {
+  const hljsCfg = this.config.highlight || {};
+  const line_threshold = options.line_threshold || hljsCfg.line_threshold || 0;
+  const shouldUseLineNumbers = typeof options.line_number === 'undefined' ? hljsCfg.line_number : options.line_number;
+  const surpassesLineThreshold = options.lines_length > line_threshold;
+  const gutter = shouldUseLineNumbers && surpassesLineThreshold;
+  const languageAttr = typeof options.language_attr === 'undefined' ? hljsCfg.language_attr : options.language_attr;
+
+  const hljsOptions = {
+    autoDetect: hljsCfg.auto_detect,
+    caption: options.caption,
+    firstLine: options.firstLine,
+    gutter,
+    hljs: hljsCfg.hljs,
+    lang: options.lang,
+    languageAttr,
+    mark: options.mark,
+    tab: hljsCfg.tab_replace,
+    wrap: hljsCfg.wrap
+  };
+  if (hljsCfg.first_line_number === 'inline') {
+    if (typeof options.firstLineNumber !== 'undefined') {
+      hljsOptions.firstLine = options.firstLineNumber;
+    } else {
+      hljsOptions.gutter = false;
+    }
+  }
+
+  if (Array.isArray(hljsCfg.exclude_languages) && hljsCfg.exclude_languages.includes(hljsOptions.lang)) {
+    // Only wrap with <pre><code class="lang"></code></pre>
+    hljsOptions.wrap = false;
+    hljsOptions.gutter = false;
+    hljsOptions.autoDetect = false;
+  }
+
+  if (!highlight) highlight = require('hexo-util').highlight;
+
+  return highlight(code, hljsOptions);
+};

lib/plugins/highlight/index.js

@@ -0,0 +1,8 @@
+'use strict';
+
+module.exports = ctx => {
+  const { highlight } = ctx.extend;
+
+  highlight.register('highlight.js', require('./highlight'));
+  highlight.register('prismjs', require('./prism'));
+};

lib/plugins/highlight/prism.js

@@ -0,0 +1,26 @@
+'use strict';
+
+// Lazy require prismjs
+let prismHighlight;
+
+module.exports = function(code, options) {
+  const prismjsCfg = this.config.prismjs || {};
+  const line_threshold = options.line_threshold || prismjsCfg.line_threshold || 0;
+  const shouldUseLineNumbers = typeof options.line_number === 'undefined' ? prismjsCfg.line_number : options.line_number;
+  const surpassesLineThreshold = options.lines_length > line_threshold;
+  const lineNumber = shouldUseLineNumbers && surpassesLineThreshold;
+
+  const prismjsOptions = {
+    caption: options.caption,
+    firstLine: options.firstLine,
+    isPreprocess: prismjsCfg.preprocess,
+    lang: options.lang,
+    lineNumber,
+    mark: options.mark,
+    tab: prismjsCfg.tab_replace
+  };
+
+  if (!prismHighlight) prismHighlight = require('hexo-util').prismHighlight;
+
+  return prismHighlight(code, prismjsOptions);
+};