feat(helper): add escape_html (#4581)

lib/plugins/helper/format.js

@@ -1,6 +1,6 @@
 'use strict';
 
-const { stripHTML, wordWrap, truncate } = require('hexo-util');
+const { stripHTML, wordWrap, truncate, escapeHTML } = require('hexo-util');
 const titlecase = require('titlecase');
 
 exports.strip_html = stripHTML;
@@ -14,3 +14,6 @@ exports.word_wrap = wordWrap;
 exports.wordWrap = wordWrap;
 
 exports.truncate = truncate;
+
+exports.escape_html = escapeHTML;
+exports.escapeHTML = escapeHTML;

lib/plugins/helper/index.js

@@ -15,13 +15,14 @@ module.exports = ctx => {
 
   helper.register('search_form', require('./search_form'));
 
-  const { strip_html, trim, titlecase, word_wrap, truncate } = require('./format');
+  const { strip_html, trim, titlecase, word_wrap, truncate, escape_html } = require('./format');
 
   helper.register('strip_html', strip_html);
   helper.register('trim', trim);
   helper.register('titlecase', titlecase);
   helper.register('word_wrap', word_wrap);
   helper.register('truncate', truncate);
+  helper.register('escape_html', escape_html);
 
   helper.register('fragment_cache', require('./fragment_cache')(ctx));
 

test/scripts/helpers/escape_html.js

@@ -0,0 +1,17 @@
+'use strict';
+
+describe('escape_html', () => {
+  const { escapeHTML } = require('../../../lib/plugins/helper/format');
+
+  it('default', () => {
+    escapeHTML('<p class="foo">Hello "world".</p>').should.eql('&lt;p class&#x3D;&quot;foo&quot;&gt;Hello &quot;world&quot;.&lt;&#x2F;p&gt;');
+  });
+
+  it('str must be a string', () => {
+    escapeHTML.should.throw('str must be a string!');
+  });
+
+  it('avoid double escape', () => {
+    escapeHTML('&lt;foo>bar</foo&gt;').should.eql('&lt;foo&gt;bar&lt;&#x2F;foo&gt;');
+  });
+});

test/scripts/helpers/index.js

@@ -4,6 +4,7 @@ describe('Helpers', () => {
   require('./debug');
   require('./css');
   require('./date');
+  require('./escape_html');
   require('./favicon_tag');
   require('./feed_tag');
   require('./fragment_cache');