refactor: Change es6 to es5

layout/_common/config.pug

 -
-  let algolia = 'undefined';
-  let env = process.env;
+  var algolia = 'undefined';
+  var env = process.env;
 
   if (theme.algolia_search.enable) {
     algolia = JSON.stringify({
@@ -17,8 +17,8 @@
   } 
 
 script.
-  let Stun = window.Stun || {};
-  let CONFIG = {
+  var Stun = window.Stun || {};
+  var CONFIG = {
     root: '!{ config.root }',
     algolia: !{algolia},
     notification: {

layout/_common/footer.pug

 footer#footer
   -
-    let footer = theme.footer
-    let nowYear = new Date().getFullYear()
-    let startYear = footer.copyright.enable ? footer.copyright.since || nowYear : nowYear
-    let endYear = footer.copyright.enable ? footer.copyright.end || nowYear : nowYear
+    var footer = theme.footer
+    var nowYear = new Date().getFullYear()
+    var startYear = footer.copyright.enable ? footer.copyright.since || nowYear : nowYear
+    var endYear = footer.copyright.enable ? footer.copyright.end || nowYear : nowYear
 
   div.footer-inner
     if footer.copyright.enable || footer.beian.enable
@@ -31,7 +31,7 @@ footer#footer
       div
         if footer.powered.enable
           span.footer-powered
-            - let HEXO_URL = "http://hexo.io/";
+            - var HEXO_URL = "http://hexo.io/";
             != _p("footer.powered", link_to(HEXO_URL, "hexo", { external: true }))
           
           if footer.powered.version
@@ -42,7 +42,7 @@ footer#footer
 
         if footer.theme.enable
           span= _p("footer.theme") + " - "
-            - let STUN_URL = "https://github.com/liuyib/hexo-theme-stun/";
+            - var STUN_URL = "https://github.com/liuyib/hexo-theme-stun/";
             != link_to(STUN_URL, "stun", { external: true })
         
           if footer.theme.version

layout/_common/head.pug

 -
-  let pageTitle = page.title || config.subtitle || ""
+  var pageTitle = page.title || config.subtitle || ""
 
   if (page.type === "tags") pageTitle = _p("title.tags")
   if (page.type === "categories") pageTitle = _p("title.categories")
@@ -11,10 +11,10 @@
 
   pageTitle ? pageTitle += " | " + config.title : pageTitle = config.title
 
-  let pageDescription = page.description || page.title || config.description || ""
-  let pageKeywords = [config.author, config.title, config.keywords].filter(i => !!i).join(", ")
-  let pageAuthor = config.email ? `${config.author}: ${config.email}` : config.author
-  let pageCopyright = config.copyright || config.author
+  var pageDescription = page.description || page.title || config.description || ""
+  var pageKeywords = [config.author, config.title, config.keywords].filter(i => !!i).join(", ")
+  var pageAuthor = config.email ? `${config.author}: ${config.email}` : config.author
+  var pageCopyright = config.copyright || config.author
 
 meta(charset="UTF-8")
 meta(http-equiv="X-UA-Compatible" content="IE=edge")

layout/_common/header.pug

@@ -19,9 +19,9 @@ header#header(
       div.header-nav-menu
         each value, name in (theme.menu || [])
           if name && value
-            - let menuItem = value.split('||')
-            - let menuItemPath = _.trim(_.get(menuItem, '[0]'))
-            - let menuItemIcon = _.trim(_.get(menuItem, '[1]'))
+            - var menuItem = value.split('||')
+            - var menuItemPath = _.trim(_.get(menuItem, '[0]'))
+            - var menuItemIcon = _.trim(_.get(menuItem, '[1]'))
             span
               a(href=menuItemPath ? menuItemPath : "/")
                 if !theme.menu_settings.text_only

layout/_common/sidebar.pug

 aside#sidebar
   div.sidebar-inner
-    - let isShowPostToc = theme.toc.enable && is_post()
+    - var isShowPostToc = theme.toc.enable && is_post()
     if isShowPostToc
       div.sidebar-nav
         span.sidebar-nav-toc.current= _p("sidebar.catalog")
@@ -8,7 +8,7 @@ aside#sidebar
     
     section(class=`${isShowPostToc ? "" : "hide"}`).sidebar-toc
       if page.content
-        - let tocMaxDepth = page.toc_max_depth || theme.toc.max_depth || 6
+        - var tocMaxDepth = page.toc_max_depth || theme.toc.max_depth || 6
         div!= toc(page.content, {list_number: theme.toc.number, max_depth: tocMaxDepth})
 
     section(class=`${isShowPostToc ? "hide" : ""}`).sidebar-overview
@@ -24,9 +24,9 @@ aside#sidebar
         div.sidebar-social
           for value, name in (theme.social || [])
             if name && value
-              - let socialItem = value.split('||')
-              - let socialLinkPath = _.trim(_.get(socialItem, '[0]'))
-              - let socialLinkIcon = _.trim(_.get(socialItem, '[1]'))
+              - var socialItem = value.split('||')
+              - var socialLinkPath = _.trim(_.get(socialItem, '[0]'))
+              - var socialLinkIcon = _.trim(_.get(socialItem, '[1]'))
               span.sidebar-social-item
                 a(href=socialLinkPath target="_blank" rel="noopener"
                     data-popover=_p(`social.${name}`) data-popover-pos="up")
@@ -42,7 +42,7 @@ aside#sidebar
       
       if theme.feed.enable
         div.sidebar-feed
-          - let feedEmail = theme.feed.email
+          - var feedEmail = theme.feed.email
           if feedEmail
             span.sidebar-feed-email
               a(href=feedEmail target="_blank" rel="noopener")
@@ -50,7 +50,7 @@ aside#sidebar
                 span Email
                 span= _p("sidebar.subscribe")
           
-          - let feedRSS = theme.feed.rss
+          - var feedRSS = theme.feed.rss
           if feedRSS
             span.sidebar-feed-rss
               a(href=url_for(feedRSS) target="_blank" rel="noopener")
@@ -59,9 +59,9 @@ aside#sidebar
                 span= _p("sidebar.subscribe")
       
       if theme.menu
-        - let menuArchives   = _.trim(_.get(theme.menu.archives.split('||'), '[0]'))
-        - let menuCategories = _.trim(_.get(theme.menu.categories.split('||'), '[0]'))
-        - let menuTags       = _.trim(_.get(theme.menu.tags.split('||'), '[0]'))
+        - var menuArchives   = _.trim(_.get(theme.menu.archives.split('||'), '[0]'))
+        - var menuCategories = _.trim(_.get(theme.menu.categories.split('||'), '[0]'))
+        - var menuTags       = _.trim(_.get(theme.menu.tags.split('||'), '[0]'))
         div.sidebar-state
           if theme.menu.archives
             div.sidebar-state-item.sidebar-state-posts
@@ -80,10 +80,10 @@ aside#sidebar
                 div.sidebar-state-item-name= _p("sidebar.tags")
       
       if theme.creative_commons.enable && theme.creative_commons.sidebar
-        - let themeCC = theme.creative_commons
-        - let ccLicense = themeCC.license && themeCC.license.toLowerCase()
-        - let ccLanguage = (themeCC.language && themeCC.language.toLowerCase()) || "en"
-        - let ccURL = `https://creativecommons.org/licenses/${ccLicense}/4.0/deed.${ccLanguage}`
+        - var themeCC = theme.creative_commons
+        - var ccLicense = themeCC.license && themeCC.license.toLowerCase()
+        - var ccLanguage = (themeCC.language && themeCC.language.toLowerCase()) || "en"
+        - var ccURL = `https://creativecommons.org/licenses/${ccLicense}/4.0/deed.${ccLanguage}`
         div.sidebar-cc
           a(href=ccURL target="_blank" rel="noopener"
               data-popover="Creative Commons" data-popover-pos="up")

layout/_components/copyright.pug

 -
-  let themeCC = theme.creative_commons
-  let ccLicense = themeCC.license && themeCC.license.toLowerCase()
-  let ccLanguage = (themeCC.language && themeCC.language.toLowerCase()) || "en"
-  let ccURL = `https://creativecommons.org/licenses/${ccLicense}/4.0/deed.${ccLanguage}`
+  var themeCC = theme.creative_commons
+  var ccLicense = themeCC.license && themeCC.license.toLowerCase()
+  var ccLanguage = (themeCC.language && themeCC.language.toLowerCase()) || "en"
+  var ccURL = `https://creativecommons.org/licenses/${ccLicense}/4.0/deed.${ccLanguage}`
 
 div.post-footer-copyright
   div.copyright-author

layout/_components/pagination.pug

 -
-  let options = {
+  var options = {
     prev_text: '<i class="fa fa-chevron-left"></i>',
     next_text: '<i class="fa fa-chevron-right"></i>',
     mid_size: 1

layout/_components/recent-posts.pug

 section#recent-posts
-  - let postLists = theme.post_list.paginate.home ? page.posts : site.posts
+  - var postLists = theme.post_list.paginate.home ? page.posts : site.posts
   - postLists.each(function (post) {
     article.post-item
       +postHeader(post)
@@ -12,7 +12,7 @@ section#recent-posts
 
       if theme.auto_excerpt && theme.auto_excerpt.enable
         - const content = strip_html(post.content)
-        - let excerpt = content.substring(0, theme.auto_excerpt.length)
+        - var excerpt = content.substring(0, theme.auto_excerpt.length)
         - content.length > theme.auto_excerpt.length ? excerpt += '......' : ''
         div!= excerpt
       else

layout/_mixins/post-header.pug

@@ -36,13 +36,13 @@ mixin postHeader(post)
           span= wordcount(post.content)
       
       if theme.post_meta.reading_time.enable
-        - let postReadingTime = theme.post_meta.reading_time
+        - var postReadingTime = theme.post_meta.reading_time
         span.post-meta-reading-time
           i(class=`fa fa-${postReadingTime.icon}`)
           
           if !theme.post_meta.icon_only
             span= _p("post.reading_time") + " "
-          - let READING_TIME_UNIT = "m";
+          - var READING_TIME_UNIT = "m";
           span= min2read(post.content, {cn: postReadingTime.speed.zh, en: postReadingTime.speed.en}) + READING_TIME_UNIT
 
       if theme.valine && theme.valine.enable && theme.valine.visitor

layout/_mixins/posts-sort.pug

 mixin articleSort(posts)
   section.article-sort
-    - let year, tmpYear
+    - var year, tmpYear
     - posts.each(function (post) {
       if post.date
         - tmpYear = full_date(post.date, "YYYY")

layout/_scripts/cdn.pug

@@ -11,9 +11,9 @@ if theme.cdn && theme.cdn.js
       script(src=url_for(url))
 
 if theme.canvas_ribbon && theme.canvas_ribbon.enable
-  - let ribbon = theme.canvas_ribbon;
+  - var ribbon = theme.canvas_ribbon;
   script(src=theme.cdn.canvas_ribbon size=ribbon.size alpha=ribbon.alpha zIndex=ribbon.zIndex)
 
 if theme.canvas_nest && theme.canvas_nest.enable
-  - let nest = theme.canvas_nest;
+  - var nest = theme.canvas_nest;
   script(src=theme.cdn.canvas_nest color=nest.color pointColor=nest.pointColor opacity=nest.opacity count=nest.count zIndex=nest.zIndex)

layout/_third-party/comments/disqus.pug

 script.
-  let disqus_config = function () {
+  var disqus_config = function () {
     this.page.url = '!{ page.permalink }';
     this.page.identifier = '!{ page.path }';
     this.page.title = '!{ page.title }';
   };
 
   (function() {
-    let d = document, s = d.createElement('script');
+    var d = document, s = d.createElement('script');
     s.src = 'https://!{ theme.disqus.shortname }.disqus.com/embed.js';
     s.setAttribute('data-timestamp', '' + +new Date());
     (d.head || d.body).appendChild(s);

layout/_third-party/comments/gitalk.pug

@@ -3,12 +3,12 @@ script(src="https://cdn.jsdelivr.net/npm/gitalk@latest/dist/gitalk.min.js")
 script(src="https://cdn.jsdelivr.net/npm/js-md5@latest/src/md5.min.js")
 
 -
-  let lang = _.get(theme, 'gitalk.language')
+  var lang = _.get(theme, 'gitalk.language')
     ? theme.gitalk.language : config.language;
 
 script.
   window.onload = function() {
-    let gitalk = new Gitalk({
+    var gitalk = new Gitalk({
       id: md5('!{ page.path }'),
       clientID: '!{ theme.gitalk.client_id }',
       clientSecret: '!{ theme.gitalk.client_secret }',

layout/_third-party/comments/gitment.pug

@@ -4,7 +4,7 @@ script(src="https://cdn.jsdelivr.net/npm/js-md5@latest/src/md5.min.js")
 
 script.
   function renderGitment() {
-    let gitment = new Gitment({
+    var gitment = new Gitment({
       id: md5('!{ page.path }'),
       owner: "!{ theme.gitment.owner }",
       repo: "!{ theme.gitment.repo }",

layout/_third-party/comments/livere.pug

 script.
   window.onload = function() {
     (function(d, s) {
-      let j, e = d.getElementsByTagName(s)[0];
+      var j, e = d.getElementsByTagName(s)[0];
       if (typeof LivereTower === 'function') { return; }
 
       j = d.createElement(s);

layout/_third-party/comments/valine.pug

@@ -3,8 +3,8 @@ script(src='https://cdn.jsdelivr.net/npm/valine@latest/dist/Valine.min.js')
 
 script.
   window.onload = function() {
-    let GUEST_INFO = ['nick', 'mail', 'link'];
-    let guest_info = '!{ theme.valine.meta }';
+    var GUEST_INFO = ['nick', 'mail', 'link'];
+    var guest_info = '!{ theme.valine.meta }';
 
     guest_info = guest_info.split(',').filter(function(item) {
       return GUEST_INFO.indexOf(item) > -1;

layout/page.pug

@@ -5,10 +5,10 @@ block content
     div.tag-cloud.main-content-layout
       div.tag-cloud-title= _p("page.tags") + " - "
         span.tag-cloud-num= site.tags.length
-      - let min_font = theme.tag_cloud ? theme.tag_cloud.min_size : 14
-      - let max_font = theme.tag_cloud ? theme.tag_cloud.max_size : 20
-      - let start_color = theme.tag_cloud ? theme.tag_cloud.start_color : "#a4d8fa"
-      - let end_color = theme.tag_cloud ? theme.tag_cloud.end_color : "#1b9ef3"
+      - var min_font = theme.tag_cloud ? theme.tag_cloud.min_size : 14
+      - var max_font = theme.tag_cloud ? theme.tag_cloud.max_size : 20
+      - var start_color = theme.tag_cloud ? theme.tag_cloud.start_color : "#a4d8fa"
+      - var end_color = theme.tag_cloud ? theme.tag_cloud.end_color : "#1b9ef3"
       div.tag-cloud-item!= tagcloud({min_font: min_font, max_font: max_font, amount: theme.tag_cloud.max_amount, color: true, start_color, end_color})
   else if (page.title === "categories")
     div.category.main-content

source/js/algolia-search.js

@@ -68,17 +68,15 @@ $(document).ready(function () {
         item: function (data) {
           var link = data.permalink ? data.permalink : CONFIG.root + data.path;
           return (
-            '<a href="' +
-            link +
-            '" class="algolia-hit-item-link">' +
-            data._highlightResult.title.value +
+            '<a href="' + link + '" class="algolia-hit-item-link">' +
+              data._highlightResult.title.value +
             '</a>'
           );
         },
         empty: function (data) {
           return (
             '<div id="algolia-hits-empty">' +
-            algolia.languages.hits_empty.replace(/\$\{query}/, data.query) +
+              algolia.languages.hits_empty.replace(/\$\{query}/, data.query) +
             '</div>'
           );
         }
@@ -102,9 +100,8 @@ $(document).ready(function () {
             return (
               stats +
               '<span class="algolia-logo pull-right">' +
-              '  <img src="' +
-              CONFIG.root +
-              'images/algolia.svg" alt="Algolia" />' +
+                '<img src="' + CONFIG.root +
+                'images/algolia.svg" alt="Algolia" />' +
               '</span>'
             );
           }

source/js/copy.js

@@ -7,26 +7,24 @@ $(document).ready(function test () {
       var lang = item
         .getAttribute('class')
         .split(/\s/)
-        .filter(e => e !== CODEBLOCK_CLASS_NAME);
-      var codeHeader = $(`
-        <figcaption class="custom">
-          <span>${lang}</span>
-        </figcaption>
-      `)[0];
+        .filter(function (e) { return e !==  CODEBLOCK_CLASS_NAME});
+      var codeHeader = $(
+        '<figcaption class="custom">' +
+          '<span>' + lang + '</span>' +
+        '</figcaption>'
+      )[0];
 
       item.insertBefore(codeHeader, $(item).children().first()[0]);
     }
   });
 
-  var $copyIcon = $(`
-    <div class="copy-button">
-      <i class="fa fa-clipboard"></i>
-    </div>
-  `);
-  var COPY_BUTTON_WRAPPER = `
-    figure.highlight figcaption,
-    .post-footer-copyright
-  `;
+  var $copyIcon = $(
+    '<div class="copy-button">' +
+      '<i class="fa fa-clipboard"></i>' +
+    '</div>'
+  );
+  var COPY_BUTTON_WRAPPER =
+    'figure.highlight figcaption, .post-footer-copyright';
 
   // Add a copy button to the selected elements.
   $(COPY_BUTTON_WRAPPER).append($copyIcon);

source/js/sidebar.js

@@ -81,7 +81,7 @@ $(document).ready(function () {
     });
 
     if (currHeading !== lastHeading) {
-      var targetLink = $(`.sidebar-toc a[href="#${currHeading}"]`);
+      var targetLink = $('.sidebar-toc a[href="#' + currHeading + '"]');
 
       // If the relevant "<a>" is not found, remain the state of the toc,
       //   either, remove styles for all active states.

source/js/utils.js

@@ -78,14 +78,14 @@ Stun.utils = Stun.$u = {
     };
 
     if (!$('.stun-alert')[0]) {
-      var $alert = $(`
-        <div class="stun-message">
-          <div class="stun-alert stun-alert-${status}">
-            <i class="stun-alert-icon fa fa-${icon[status]}"></i>
-            <span class="stun-alert-description">${text}</span>
-          </div>
-        </div>
-      `);
+      var $alert = $(
+        '<div class="stun-message">' +
+          '<div class="stun-alert stun-alert-' + status + '">' +
+            '<i class="stun-alert-icon fa fa-' + icon[status] + '"></i>' +
+            '<span class="stun-alert-description">' + text + '</span>' +
+          '</div>' +
+        '</div>'
+      );
 
       $('body').append($alert);
     }
@@ -167,8 +167,11 @@ Stun.utils = Stun.$u = {
   addIconToExternalLink: function (selector) {
     if (!$(selector)[0]) return;
     
-    var $icon = $(`<i class="external-link fa fa-${
-      CONFIG.external_link.icon_name}"></i>`);
+    var $icon = $(
+      '<i class="external-link fa fa-' +
+        CONFIG.external_link.icon_name +
+      '"></i>'
+    );
     $(selector).find('a[target="_blank"]').append($icon);
   },
   // Back the page to top.