Revert "fix(backtick_code): handle empty code blocks (#5206)" (#5257)

This reverts commit c62909d.

lib/plugins/filter/before_post_render/backtick_code_block.ts

@@ -1,4 +1,4 @@
-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+|$)/gm;
+const rBacktick = /^((?:[^\S\r\n]*>){0,3}[^\S\r\n]*)(`{3,}|~{3,})[^\S\r\n]*((?:.*?[^`\s])?)[^\S\r\n]*\n((?:[\s\S]*?\n)?)(?:(?:[^\S\r\n]*>){0,3}[^\S\r\n]*)\2[^\S\r\n]?(\n+|$)/gm;
 const rAllOptions = /([^\s]+)\s+(.+?)\s+(https?:\/\/\S+|\/\S+)\s*(.+)?/;
 const rLangCaption = /([^\s]+)\s*(.+)?/;
 

test/scripts/filters/backtick_code_block.js

@@ -650,19 +650,5 @@ describe('Backtick code block', () => {
       codeBlock(data);
       data.content.should.eql('<hexoPostRenderCodeBlock>' + expected + '</hexoPostRenderCodeBlock>');
     });
-
-    it('handle empty code block', () => {
-      const data = {
-        content: [
-          '``` js',
-          '```',
-          '# New line',
-          '``` js',
-          '```'
-        ].join('\n')
-      };
-      codeBlock(data);
-      data.content.match(/<hexoPostRenderCodeBlock>/g).length.should.eql(2);
-    });
   });
 });