feat(backtick_code): remove strip-indent & add escape

lib/plugins/filter/before_post_render/backtick_code_block.js

@@ -1,20 +1,27 @@
 'use strict';
 
-const stripIndent = require('strip-indent');
 let highlight, prismHighlight;
 
 const rBacktick = /^((?:[^\S\r\n]*>){0,3}[^\S\r\n]*)(`{3,}|~{3,}) *(.*) *\n([\s\S]+?)\s*\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 hljsCfg = this.config.highlight || {};
   const prismCfg = this.config.prismjs || {};
 
-  // neither highlight or prismjs is enabled, return directly.
-  if (!hljsCfg.enable && !prismCfg.enable) return;
-
   data.content = data.content.replace(rBacktick, ($0, start, $2, _args, content, end) => {
+    // neither highlight or prismjs is enabled, return escaped content directly.
+    if (!hljsCfg.enable && !prismCfg.enable) {
+      return start
+      + '<escape>'
+      + escapeSwigTag(content)
+      + '</escape>'
+      + end;
+    }
+
     // Extrace langauge and caption of code blocks
     const args = _args.split('=').shift();
     let lang, caption;
@@ -54,7 +61,7 @@ function backtickCodeBlock(data) {
         lang
       };
 
-      content = prismHighlight(stripIndent(content), options);
+      content = prismHighlight(content, options);
     } else if (hljsCfg.enable) {
       if (!highlight) highlight = require('hexo-util').highlight;
 
@@ -81,14 +88,14 @@ function backtickCodeBlock(data) {
         }
       }
 
-      content = highlight(stripIndent(content), options);
+      content = highlight(content, options);
     }
 
     return start
-        + '<escape>'
-        + content.replace(/{/g, '&#123;').replace(/}/g, '&#125;')
-        + '</escape>'
-        + end;
+      + '<escape>'
+      + escapeSwigTag(content)
+      + '</escape>'
+      + end;
   });
 }